Steroid hormones,synthesized from cholesterol via cytochrome P450 enzymes,are categorized into adrenocortical hormones and sex hormones.Their monitoring is crucial in clinical and research settings for evaluating dise...Steroid hormones,synthesized from cholesterol via cytochrome P450 enzymes,are categorized into adrenocortical hormones and sex hormones.Their monitoring is crucial in clinical and research settings for evaluating disease risk and physiological shifts,as well as for managing medical conditions.The structural similarity and concentration differences of steroid hormones in biological samples create significant challenges for analysis.Traditional immunoassays(IAs)are now less effective due to cross-reactivity and other limitations.Advances in mass spectrometry(MS),especially liquid chromatography-tandem mass spectrometry,have become preferred for steroid hormone detection,establishing a new“gold standard”in the field.The paper examines the influence of various pretreatment methods on the sensitivity and detection limits of steroid hormones,including protein precipitation,liquid–liquid extraction,solid-phase extraction,cold-induced phase separation technique,and derivatization technique,providing a crucial reference for clinical steroid detection.This paper reviews IAs and MS methods used recently(2013–2023)for detecting endogenous steroid hormones,highlighting their analytical strengths and limitations.It also discusses recent advancements and future prospects in both IA and MS methodologies.展开更多
Carbon nanotube fibers(CNTFs)fabricated using a novel“wet-pulling”technique were evaluated for electrochemical detection of dopamine(DA).To enhance the sensitivity,we employed an electrochemical oxidation pretreatme...Carbon nanotube fibers(CNTFs)fabricated using a novel“wet-pulling”technique were evaluated for electrochemical detection of dopamine(DA).To enhance the sensitivity,we employed an electrochemical oxidation pretreatment and twisting of CNTFs and investigated the performance by cyclic voltammetry(CV)and chronoamperometry(CA).The synergetic eff ect of twisting and pre-oxidation boosted the sensitivity of modified CNTFs compared to the as-obtained CNTFs due to the introduction of new active sites for efficient trapping of DA molecules.For the oxidized twisted CNTFs,we achieved a sensitivity of 10.8μA·μM^(–1)·cm^(–2)and the limit of detection of 330 nM in the case of CV,and 6.4μA·μM-1·cm-2and 102 nM in the case of CA,respectively.The CNTFs showed good potential for an in vitro application,maintaining sufficient sensitivity under various conditions.When coupled with the suited mechanical properties of CNTFs,the results highlight the prospect of implantable and flexible sensors.展开更多
This study employs an N-carboxyanhydride ring-opening polymerization(NCA ROP)signal amplification strategy to construct a novel sensing system for the simple and rapid detection of tobacco mosaic virus RNA(tRNA).In th...This study employs an N-carboxyanhydride ring-opening polymerization(NCA ROP)signal amplification strategy to construct a novel sensing system for the simple and rapid detection of tobacco mosaic virus RNA(tRNA).In the developed fluorescent biosensor,carboxylated biomagnetic beads serve as carriers for target capture based on the complementary pairing of the aptamer bases.Subsequently,NCA ROP fluorescent peptides are utilized as highly biocompatible signal carriers to achieve sensitive detection of the target.Under the optimal conditions,the biosensor exhibits a broad linear detection range from 1 pM to 10 nM,with a detection limit as low as 0.085 pM.Furthermore,the fluorescent aptamer biosensor demonstrates robust affinity and reliability in recovery experiments involving healthy R ehmannia glutinosa leaf total RNA.This work establishes a robust platform for tRNA analysis,facilitating real-time and early diagnosis of various plant viruses.展开更多
A simple analytical assay based on ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)and micro-solid phase extraction(μ-SPE)techniques was established for the quantification of polypro...A simple analytical assay based on ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)and micro-solid phase extraction(μ-SPE)techniques was established for the quantification of polypropylene glycol 4K(PPG4K)polymers in cellular samples.Afterμ-SPE,the analytes were concentrated and separated on a reversed phase C18column.Collision induced dissociation(CID)was tested and the parent ions of PPG4K polymers were fragmented with a relatively high value of declustering potential(DP)in the ion source.Numerous fragment ions associated with the structure of PPG4K were generated in ion source at m/z 58n+1([M+H]+),58n+18([M+NH_(4)]^(+)),58n+23([M+Na]+)and 58n+39([M+K]+),respectively.[M+NH_(4)]^(+)adducts were selected and further fragmented in the second quadrupole of the UHPLC-MS/MS system.Multiple reaction monitoring(MRM)transition at m/z 598.4[M+NH_(4)]^(+)(58×10+18)→175.0 was selected to determine PPG4K polymers in cellular samples owing to its excellent selectivity and higher sensitivity compared with the other MRM transitions.The developed analytical assay was successfully applied to the bioanalysis of PPG4K polymers in cellular samples.The lower limit of quantification(LLOQ)was 10 ng/mL and the limit of detection(LOD)was 2.5 ng/mL for PPG4K polymers.This study provides a novel analytical strategy for the determination of PPG4K polymers,which is coupled withμ-SPE and the selection of[M+NH_(4)]^(+)adduct strategy to enhance sensitivity.展开更多
As the key factor in brain development and fat metabolism,choline is widely present in foods,especially in health care and dairy products.In this study,a simple,rapid,sensitive,and cost-eff ective method was proposed ...As the key factor in brain development and fat metabolism,choline is widely present in foods,especially in health care and dairy products.In this study,a simple,rapid,sensitive,and cost-eff ective method was proposed for choline detection based on luminol derivate(L012)doped amino silica nanoparticles(L012@SiNPs-NH_(2)).L012@SiNPs-NH_(2)exhibited a 47-fold increase in the electrochemiluminescence(ECL)response and much better uniformity and dispersion compared with conventional luminol-doped silica nanoparticles(Luminol@SiNPs).We thus constructed an ECL biosensor based on the L012@SiNPs-NH_(2)/H_(2)O_(2)system,in which co-reactant H_(2)O_(2)is generated from dissolved oxygen during the process of oxidation of choline by choline oxidase.Significantly,the ECL biosensor shows a linear relationship between ECL intensity and choline concentration in the range of 1–5000μM,with a low limit of detection of 1μM.Additionally,the recovery tests from milk powders were conducted,demonstrating its practical application potential,which could be expanded to other oxidase-related analytes detection.It greatly broadened the application of L012 based nano-emitters in biological,food,and clinical analysis.展开更多
Brucellosis is a highly infectious anthropozoonotic disease caused by the genus Brucella,which is the pathogenic bacteria in public health risk and occupation exposure.Therefore,rapid detection and identification of B...Brucellosis is a highly infectious anthropozoonotic disease caused by the genus Brucella,which is the pathogenic bacteria in public health risk and occupation exposure.Therefore,rapid detection and identification of Brucella is crucial for controlling and managing the prevalence of brucellosis.In this work,matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS)combined with machine learning(ML)algorithms was developed to identify Brucella isolates at the species level rapidly.A total of 1440 MALDI spectral data from 59 strains of B.melitensis(23 strains of B.melitensis bv.1 and 36 strains of B.melitensis bv.3)were obtained.Four ML algorithms including support vector machine(SVM),random forest(RF),extreme gradient boosting(XGBoost),and logistic regression(LR)were compared for typing Brucella species.The area under receiver operating characteristic(ROC)curve,precision-recall ratio(PR),accuracy,specificity,and sensitivity were used to evaluate the performances of diff erent ML algorithms.These results showed that MALDI-TOF MS combined with the XGBoost algorithm is the best method for typing Brucella species with good performances,demonstrating the significant potential applications in the diagnosis,control,and epidemiology of brucellosis.展开更多
Detecting trace pesticide residues in food products is crucial for ensuring food safety.Terahertz technology has demonstrated significant advantages in chemical and biological sensing by utilizing the vibrational sign...Detecting trace pesticide residues in food products is crucial for ensuring food safety.Terahertz technology has demonstrated significant advantages in chemical and biological sensing by utilizing the vibrational signatures inherent to molecules in the terahertz spectrum and leveraging the amplified electric fields facilitated by metamaterials.In this work,we introduce a novel method for imidacloprid(IMI)pesticide residue detection using the rod-shaped terahertz metamaterial(RSTM)with a composite interface of gold and conductive polymer polyaniline(PANI).The core mechanism of this method relies on the binding of IMI to PANI,which alters the resonance intensity and frequency of the Au-PANI-RSTM.Specifically,the RSTM parameters are determined using computer simulation technology(CST),and the RSTM structure is engraved on the Au-PANI surface using laser direct writing technology.Further characterization using mid-infrared spectroscopy(MIR)and X-ray photoelectron spectroscopy(XPS)techniques reveals that the stable bonding between PANI and IMI is facilitated by hydrogen bonding and covalent bonding.The detection limit of Au-PANI-RSTM deposited with 20 segments for IMI is 0.46 ppm,which complies with the maximum residue limit for IMI stipulated in the Chinese National Standard.展开更多
A rapid and effective analytical method was developed for the detection of triclosan in wastewater samples using a hydrophobic deep eutectic solvent thymol-lidocaine(Thy-Lid,molar ratio of 1:1)and dispersive liquid-li...A rapid and effective analytical method was developed for the detection of triclosan in wastewater samples using a hydrophobic deep eutectic solvent thymol-lidocaine(Thy-Lid,molar ratio of 1:1)and dispersive liquid-liquid microextraction(DLLME).The analyte was determined by high-performance liquid chromatography with a photodiode array detector(HPLC-PDA),obtaining a detection limit of 0.38μg/L,a recovery rate of 99%,and an enrichment factor of the analyte in the water of 80.A factorial design was used to optimize the analytical signal to improve the time and reduce the cost of the method.Combining this chemometric optimization tool with a green solvent and DLLME allows for obtaining an analytical methodology aligned with the principles of green analytical chemistry,enabling the inexpensive,selective,and rapid analysis of triclosan in real wastewater.展开更多
The hybridization chain reaction(HCR)is a widely used nucleic acid amplification technique that is essential for gene expression analysis and disease diagnosis.Despite its inherent stability,traditional HCR often suff...The hybridization chain reaction(HCR)is a widely used nucleic acid amplification technique that is essential for gene expression analysis and disease diagnosis.Despite its inherent stability,traditional HCR often suffers from low detection efficiency,which necessitates the use of supplementary molecular technologies to enhance its performance for detecting trace samples.Drawing insights from confinement theory,we have proposed a novel cruciform DNA scaffold-based HCR reaction system(C-HCR).In our approach,the DNA cruciform is assembled with the initiating probes of the HCR reaction through specific binding between adenine-rich and thymine-rich regions.This assembly with derived chains does not interfere with the HCR process.When a target is present,traditional HCR reactions yield long-chain linear products.However,the incorporation of the DNA cruciform in C-HCR leads to the formation of network-like products,which create favorable conditions for efficient molecular collisions and,in turn,promote high detection efficiency within the system.We utilized miR-21 and miR-27a as model targets to validate our design concept.Our results revealed that the miRNA-specific HCR system for miR-21 and miR-27a achieved significant increases in detection efficiency of 27.8%and 50%,respectively,demonstrating the feasibility and versatility of our design.This study offers a new strategy for enzyme-free amplification systems.展开更多
A novel composite of aptamer-based Ti_(3)C_(2)T_(x)and molecularly imprinted polymer(Apt-Ti_(3)C_(2)T_(x)-MIP)with double recognition property was prepared for sensitive electrochemical detection of ofloxacin(OFL).Fir...A novel composite of aptamer-based Ti_(3)C_(2)T_(x)and molecularly imprinted polymer(Apt-Ti_(3)C_(2)T_(x)-MIP)with double recognition property was prepared for sensitive electrochemical detection of ofloxacin(OFL).First,Ti_(3)C_(2)T_(x)@SiO_(2)was synthesized using multi-layer Ti_(3)C_(2)T_(x)and tetraethyl orthosilicate(TEOS)in alkaline conditions.Amino Ti_(3)C_(2)T_(x)@SiO_(2)was then prepared through Ti_(3)C_(2)T_(x)@SiO_(2)in the presence of(3-aminopropyl)triethoxysilane.Carboxyl OFL aptamers were then grafted onto amino Ti_(3)C_(2)T_(x)@SiO_(2)to prepare aptamer-modified Ti_(3)C_(2)T_(x)@SiO_(2).A novel composite of Apt-Ti_(3)C_(2)T_(x)-MIP was prepared with sol–gel method in the presence of Ti_(3)C_(2)T_(x)@SiO_(2)-Apt-OFL and TEOS.The Apt-Ti_(3)C_(2)T_(x)-MIP sensor exhibited double recognition for OFL because of aptamer specificity and imprinted binding sites.The electrochemical response of Apt-Ti_(3)C_(2)T_(x)-MIP sensor for OFL was 2.29 and 2.75 times that of Apt-Ti_(3)C_(2)T_(x)-NIP and Ti_(3)C_(2)T_(x)-MIP sensors,respectively,demonstrating the double recognition of Apt-Ti_(3)C_(2)T_(x)-MIP for OFL.The Apt-Ti_(3)C_(2)T_(x)-MIP sensor with double recognition displayed a linear peak current to OFL centration from 0.025 to 10μM with a detection limit of 10 nM.The Apt-Ti_(3)C_(2)T_(x)-MIP sensor had excellent selectivity for OFL and has been successfully applied to the detection of OFL in a wastewater sample.展开更多
Fluorescent nanoparticles offer promising applications for bioimaging due to their exceptional attributes,including heightened fluorescence brightness and prolonged photo-stability,surpassing those of traditional fluo...Fluorescent nanoparticles offer promising applications for bioimaging due to their exceptional attributes,including heightened fluorescence brightness and prolonged photo-stability,surpassing those of traditional fluorescent dyes.However,the selection of suitable materials and surface functionalization strategies for the synthesis of efficient fluorescent nanoparticles remains a significant challenge in this field.Here,we report a facile synthesis method of fluorescent nanoparticles,which is rationally designed by coating polydopamine(PDA)on eutectic Gallium-Indium(EGaIn,a liquid metal(LM))under ultrasonic waves to prepare the fluorescent PDA/LM nanoparticles.The fluorescence intensity of the PDA/LM nanoparticles is eightfold greater than that of the pristine PDA nanoparticles and can be quenched by Pb^(2+).It demonstrates that the PDA/LM nanoparticles exhibit superior analytical performance for Pb^(2+)over a linear range from 10 to 100μg/L,with a detection limit of 3μg/L.This probe can be used to detect Pb^(2+)in different vessels.展开更多
Traditional fluorescent emitters cannot eff ectively utilize triplet excitons owing to the spin statistical limitation, thus their electrochemiluminescence(ECL) efficiency(Φ_(ECL)) is relatively low. Improving the ut...Traditional fluorescent emitters cannot eff ectively utilize triplet excitons owing to the spin statistical limitation, thus their electrochemiluminescence(ECL) efficiency(Φ_(ECL)) is relatively low. Improving the utilization efficiency of triplet excitons is of great significance for developing efficient luminescent materials. Here we designed a hot exciton molecule(NZ2TPA) containing highly efficient chromophore naphthothiadiazole as an electron acceptor and triphenylamine(TPA) with aggregation induced emission(AIE) property as the strong electron donor to synthesize an ECL nanoemitter-NZ2TPA nanoparticles(NT NPs). The hybridized local and charge-transfer(HLCT) excited state of NZ2TPA achieved a high exciton utilization through the reverse intersystem crossing from higher triplet states( h RISC). The combination of HLCT and AIE characteristics endowed NT NPs with superior ΦECLover other nanoemitters, which provided an excellent material for the design of highly sensitive ECL biosensors. Using alkaline phosphatase(ALP) as an analyte model, a “signal-on” ECL biosensing approach was constructed by combining the quenching of manganese dioxide nanosheets(MnO_(2)NSs) on ECL emission of NT NPs and the reduction of MnO_(2)by ascorbic acid produced from ALP-catalyzed dephosphorylation, which showed a detectable range of 0.004-400 U/L with a detection limit of 0.57 mU/L. The excellent performance demonstrated the immense potential of organic nanomaterials through combining HLCT and AIE properties to improve ΦECL.展开更多
New pollutants(NPs)are characterized by their concealment,persistence,and bioaccumulation and have emerged as a major concern in the international community.The screening and identification of NPs are fundamental prer...New pollutants(NPs)are characterized by their concealment,persistence,and bioaccumulation and have emerged as a major concern in the international community.The screening and identification of NPs are fundamental prerequisites for research into their environmental behavior,toxicological eff ects,remediation,and other related areas.Molecularly imprinted ratiometric fluorescence(MI-RFL)sensors,known for their high selectivity,sensitivity,rapidity,and convenience,have garnered significant attention in the analytical detection of NPs.This review focuses on three major categories of NPs,persistent organic pollutants,environmental endocrine disruptors,and antibiotics,and examines recent advancements in MI-RFL sensors for the screening,identification,and detection of NPs since 2018.We briefly outline the preparation technologies and strategies for molecularly imprinted polymers(MIPs)and the potential detection principles of these sensors.Additionally,we highlight the fluorescence sources and construction strategies of MI-RFL sensors.The review also summarizes wellconstructed multiple MI-RFL sensors for the rapid detection of various NPs residues in complicated matrices,providing typical application examples in the fields of food safety,environmental monitoring,and biological medicine.Finally,we propose future perspectives on the construction and applications of MI-RFL sensors for detecting NPs.展开更多
Due to the important role of vitamin D in metabolism,developing a method for rapid and high-throughput analysis of vitamin D and its metabolites is crucial.However,the current clinical diagnostic methods have the disa...Due to the important role of vitamin D in metabolism,developing a method for rapid and high-throughput analysis of vitamin D and its metabolites is crucial.However,the current clinical diagnostic methods have the disadvantage of complicated operating procedures.In the present study,a technique combining immunocapture with mass spectrometry for rapidly detecting of 25-hydroxyvitamin D_(3)in serum was developed.This method employs an antibody–antigen reaction to specifically enrich 25-hydroxyvitamin D_(3)and remove complex interfering substances.Qualitative and quantitative analysis of 25-hydroxyvitamin D_(3)was achieved by nano-electrospray ionization-mass spectrometry(nano-ESI–MS).The method exhibited good linearity in the range of 1–100 ng/mL with satisfactory recovery and repeatability.The proposed method is promising for high-throughput and rapid analysis of small molecules with mass spectrometry.And it can potentially be combined with portable mass spectrometers to meet the requirements of point-of-care detection.展开更多
Several organic polymers and sol-gel derived porous silica were investigated as cladding material of a fused silica optical fi ber as well as a solid phase microextraction (SPME) material in an eff ort to develop an e...Several organic polymers and sol-gel derived porous silica were investigated as cladding material of a fused silica optical fi ber as well as a solid phase microextraction (SPME) material in an eff ort to develop an evanescent wave optical fi ber chemical sensor (EW-OFCS) for detecting acetylsalicylic acid (ASA) in aqueous sample solutions.A dip-coating method was adopted for coating a polymer on the fi ber core surface of a bent optical fi ber probe (BOFP) as a cladding/SPME membrane.Among the polymers investigated,it was found that cellulose triacetate (CTA) can function as a SPME material for concentrating ASA from aqueous sample solution into CTA membrane coated on BOFP surface.The ASA concentrated into the CTA membrane was detected by passing a light beam through the BOFP and detecting the fi ber optic EW absorption signal at ASA’s intrinsic peak absorption wavelength (310 nm).No chemical reaction was involved in the developed sensor and no chemical reagent is needed in using the sensor for detecting ASA in an aqueous sample solution.The sensor response is reversible because SPME is a reversible process.This SPME-EW-OFCS achieved a detection limit of 0.72μg/mL for detecting ASA in aqueous sample solutions.The sensor has been used for analyzing ASA in pharmaceutical Aspirin products,and obtained analytical results agree well with a conventional UV/Vis absorption spectrometric method.展开更多
This study aimed to identify new compounds capable of decreasing pancreatic lipase(PL)catalytic activity.A panel of structurally related chalcones with hydroxy and chloro substituents was chosen,and their inhibitory e...This study aimed to identify new compounds capable of decreasing pancreatic lipase(PL)catalytic activity.A panel of structurally related chalcones with hydroxy and chloro substituents was chosen,and their inhibitory eff ects on the targeted enzyme were assessed.This work also optimized the conditions for UV/Vis spectrophotometric and fluorimetric microanalysis systems and,whenever possible,a structure–activity relationship analysis was performed.The obtained results showed the eff ectiveness of both methodologies in assessing the inhibition of PL catalytic activity.Some of the tested chalcones exhibited notable inhibitory eff ects on PL activity.Remarkably,the presence of hydroxy or chloro substituents appears to enhance the observed inhibitory activities of these compounds.展开更多
A simplistic and novel electrochemical sensor for selectively detecting the essential amino acid tryptophan in dietary supplements was fabricated on a pencil graphite electrode modified with a tryptophan-based dipepti...A simplistic and novel electrochemical sensor for selectively detecting the essential amino acid tryptophan in dietary supplements was fabricated on a pencil graphite electrode modified with a tryptophan-based dipeptide.The dipeptide was synthesized using common synthetic strategy for amino acid couplings.The modified electrode was characterized by scanning electron microscopy,impedance spectroscopy,cyclic voltammetry,and infrared spectroscopy.Differential pulse voltammetry was used to study the electrochemical response of the fabricated electrode to tryptophan in dietary supplements.Under the optimized experimental conditions,a distinct oxidation peak at+0.671 V corresponding to tryptophan was noticed in differential pulse voltammetry,which indicated the detection of tryptophan by the fabricated electrode.The oxidation peak current for tryptophan was found to be linear within a concentration range of 10–350μM with a lower detection limit of 1.2μM,and the sensitivity of the fabricated electrode was 6.9μA/μM/cm^(2).Excellent selectivity,permissible reproducibility,and good stability of the sensor make it undoubtedly suitable for determining tryptophan in dietary supplements.展开更多
Trimethylamine N-oxide(TMAO),a small microbial metabolite,is bioactive and closely related to cardiovascular diseases(CVD)and chronic kidney diseases.Studying functions of TMAO calls for convenient and accurate method...Trimethylamine N-oxide(TMAO),a small microbial metabolite,is bioactive and closely related to cardiovascular diseases(CVD)and chronic kidney diseases.Studying functions of TMAO calls for convenient and accurate methods to quantify TMAO.Herein,we proposed two novel chemiluminescent(CL)probes by grafting halogenated propyl ether to Schaap's dioxetane skeleton.The detection is based on a unique oxidation reaction using TMAO as the oxidant,which uncages the luminescent scaff old to emit green luminescence.Reasonable selectivity and sensitivity were achieved on the assay with iodinated probe CLTI.An excellent linear correlation(R^(2)=0.997)of CL intensity versus TMAO concentration was found at low micromolar ranges(5-50μM).The quantification of TMAO in partial marine fishes,as well as the isolated organs and tissues of Sequoia fishes,has been realized.This study presented probably the first CL method for TMAO determination.展开更多
The antimony(Sb)electrode,despite its prevalent use for pH detection in complex environments,suffers from severe potential drift due to poor corrosion resistance,thereby impeding long-term or online applications.Inter...The antimony(Sb)electrode,despite its prevalent use for pH detection in complex environments,suffers from severe potential drift due to poor corrosion resistance,thereby impeding long-term or online applications.Intermetallic compounds show excellent resistance to corrosion and oxidation,presenting a promising avenue for improving the stability of the Sb electrode.Therefore,we fabricate an intermetallic compound-doped Sb electrode by adding various cobalt(Co)contents to improve the stability of the Sb electrode without compromising the inherent pH response.It's observed that the alloy electrode exhibits a significant reduction in surface roughness,corrosion product Sb_(2)O_(3)content,cracks,and Sb exfoliation compared to the pure Sb electrode after the electrochemical tests,and the effect becomes more pronounced as the Co content increases.The electrochemical tests further reveal that the alloy electrode exhibits better corrosion resistance than the pure Sb in various solutions,with the alloy electrode containing 80 at%Sb showing the highest corrosion resistance.Moreover,the alloy electrode containing 80 at%Sb also shows excellent sensitivity and anti-interference ability,high accuracy and reproducibility,low hysteresis,and better long-term stability,especially in seawater.These findings suggest that inexpensive Co doping significantly enhances corrosion resistance,thereby reducing electrode surface alterations and eventually improving the potential stability of pure Sb electrodes without affecting the inherent pH response.Furthermore,the obtained results provide an experimental basis for the long-term operation of the alloy pH electrode in complex environments such as seawater without frequent maintenance.展开更多
Agarwood is a resinous wood produced by plants of the genus Aquilaria in the Thymelaeaceae family after being injured.The wide distribution of origins and the complexity of formation have led to various species of aga...Agarwood is a resinous wood produced by plants of the genus Aquilaria in the Thymelaeaceae family after being injured.The wide distribution of origins and the complexity of formation have led to various species of agarwood.The preciousness,universality of application and scarcity of resources bring difficulties to the quality control of agarwood,the in-situ ionization technique shows great potential in the rapid and accurate identification of valuable herbal medicines.In this paper,based on the combination of paper capillary spray and miniature mass spectrometry,different kinds of agarwood and counterfeits were directly added onto the chromatography paper,the active ingredients were extracted by solvent and then carried out by the portable miniature mass spectrometry,which could be implemented to perform an effective and on-site analysis,and the whole process only took about 1 min.Characteristic highly oxidized 2-(2-phenylethyl)chromones and flindersia-type 2-(2-phenylethyl)chromones were detected in authentic agarwood,and other characteristic flindersia-type 2-(2-phenylethyl)chromones were detected in authentic Kynam agarwood(special variety of agarwood),while the above characteristic components were not detected in counterfeits.Furthermore,an artificial intelligence model based on random forest algorithm was established for automatic identification.This approach is versatile,unfettered by location or environmental constraints,making it particularly valuable in the identification of precious Chinese herbal medicines.展开更多
基金China Postdoctoral Science Foundation(2021M702937)for the financial support。
文摘Steroid hormones,synthesized from cholesterol via cytochrome P450 enzymes,are categorized into adrenocortical hormones and sex hormones.Their monitoring is crucial in clinical and research settings for evaluating disease risk and physiological shifts,as well as for managing medical conditions.The structural similarity and concentration differences of steroid hormones in biological samples create significant challenges for analysis.Traditional immunoassays(IAs)are now less effective due to cross-reactivity and other limitations.Advances in mass spectrometry(MS),especially liquid chromatography-tandem mass spectrometry,have become preferred for steroid hormone detection,establishing a new“gold standard”in the field.The paper examines the influence of various pretreatment methods on the sensitivity and detection limits of steroid hormones,including protein precipitation,liquid–liquid extraction,solid-phase extraction,cold-induced phase separation technique,and derivatization technique,providing a crucial reference for clinical steroid detection.This paper reviews IAs and MS methods used recently(2013–2023)for detecting endogenous steroid hormones,highlighting their analytical strengths and limitations.It also discusses recent advancements and future prospects in both IA and MS methodologies.
基金supported by Russian Science Foundation,21-73-10288Ministry of Science and Higher Education of the Russian Federation,FZSR-2024-0005。
文摘Carbon nanotube fibers(CNTFs)fabricated using a novel“wet-pulling”technique were evaluated for electrochemical detection of dopamine(DA).To enhance the sensitivity,we employed an electrochemical oxidation pretreatment and twisting of CNTFs and investigated the performance by cyclic voltammetry(CV)and chronoamperometry(CA).The synergetic eff ect of twisting and pre-oxidation boosted the sensitivity of modified CNTFs compared to the as-obtained CNTFs due to the introduction of new active sites for efficient trapping of DA molecules.For the oxidized twisted CNTFs,we achieved a sensitivity of 10.8μA·μM^(–1)·cm^(–2)and the limit of detection of 330 nM in the case of CV,and 6.4μA·μM-1·cm-2and 102 nM in the case of CA,respectively.The CNTFs showed good potential for an in vitro application,maintaining sufficient sensitivity under various conditions.When coupled with the suited mechanical properties of CNTFs,the results highlight the prospect of implantable and flexible sensors.
基金supported by the Project of tacking of key scientifi c and technical problems in Henan Province(192102310033)。
文摘This study employs an N-carboxyanhydride ring-opening polymerization(NCA ROP)signal amplification strategy to construct a novel sensing system for the simple and rapid detection of tobacco mosaic virus RNA(tRNA).In the developed fluorescent biosensor,carboxylated biomagnetic beads serve as carriers for target capture based on the complementary pairing of the aptamer bases.Subsequently,NCA ROP fluorescent peptides are utilized as highly biocompatible signal carriers to achieve sensitive detection of the target.Under the optimal conditions,the biosensor exhibits a broad linear detection range from 1 pM to 10 nM,with a detection limit as low as 0.085 pM.Furthermore,the fluorescent aptamer biosensor demonstrates robust affinity and reliability in recovery experiments involving healthy R ehmannia glutinosa leaf total RNA.This work establishes a robust platform for tRNA analysis,facilitating real-time and early diagnosis of various plant viruses.
基金supported by the Open funding of the Cancer Hospital of Dalian University of Technology,China(2024-ZLKF-33)the Natural Science Foundation of Liaoning Province,China(2023-MSBA-018)the Fundamental Research Funds for the Central Universities,China(DUT21RC(3)057 and DUT23YG228)。
文摘A simple analytical assay based on ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)and micro-solid phase extraction(μ-SPE)techniques was established for the quantification of polypropylene glycol 4K(PPG4K)polymers in cellular samples.Afterμ-SPE,the analytes were concentrated and separated on a reversed phase C18column.Collision induced dissociation(CID)was tested and the parent ions of PPG4K polymers were fragmented with a relatively high value of declustering potential(DP)in the ion source.Numerous fragment ions associated with the structure of PPG4K were generated in ion source at m/z 58n+1([M+H]+),58n+18([M+NH_(4)]^(+)),58n+23([M+Na]+)and 58n+39([M+K]+),respectively.[M+NH_(4)]^(+)adducts were selected and further fragmented in the second quadrupole of the UHPLC-MS/MS system.Multiple reaction monitoring(MRM)transition at m/z 598.4[M+NH_(4)]^(+)(58×10+18)→175.0 was selected to determine PPG4K polymers in cellular samples owing to its excellent selectivity and higher sensitivity compared with the other MRM transitions.The developed analytical assay was successfully applied to the bioanalysis of PPG4K polymers in cellular samples.The lower limit of quantification(LLOQ)was 10 ng/mL and the limit of detection(LOD)was 2.5 ng/mL for PPG4K polymers.This study provides a novel analytical strategy for the determination of PPG4K polymers,which is coupled withμ-SPE and the selection of[M+NH_(4)]^(+)adduct strategy to enhance sensitivity.
基金supported by Natural Science Foundation of Shandong Province(ZR2022QB033)National Natural Science Foundation of China(22304015)+5 种基金the Scientifi c Research Start-up Fund of Binzhou Medical University(BY2022KYQD43BY2021KYQD21)Taishan Scholars Program of Shandong Province(tsqn202103112)the Development Plan of Youth Innovation Team in Colleges and Universities of Shandong Province(2021KJ052)the Supporting Fund for Leading Talents above Provincial Level in Yantai(10073803)the Collaborative Innovation Program of Hefei Science Center(2022HSC-CIP012)。
文摘As the key factor in brain development and fat metabolism,choline is widely present in foods,especially in health care and dairy products.In this study,a simple,rapid,sensitive,and cost-eff ective method was proposed for choline detection based on luminol derivate(L012)doped amino silica nanoparticles(L012@SiNPs-NH_(2)).L012@SiNPs-NH_(2)exhibited a 47-fold increase in the electrochemiluminescence(ECL)response and much better uniformity and dispersion compared with conventional luminol-doped silica nanoparticles(Luminol@SiNPs).We thus constructed an ECL biosensor based on the L012@SiNPs-NH_(2)/H_(2)O_(2)system,in which co-reactant H_(2)O_(2)is generated from dissolved oxygen during the process of oxidation of choline by choline oxidase.Significantly,the ECL biosensor shows a linear relationship between ECL intensity and choline concentration in the range of 1–5000μM,with a low limit of detection of 1μM.Additionally,the recovery tests from milk powders were conducted,demonstrating its practical application potential,which could be expanded to other oxidase-related analytes detection.It greatly broadened the application of L012 based nano-emitters in biological,food,and clinical analysis.
基金supported by the Science and Technology Service Network Initiative(KFJ-STS-QYZD-188)National Natural Science Foundation of China(22476064)Fundamental Research Funds for the Central Universities(21624203)。
文摘Brucellosis is a highly infectious anthropozoonotic disease caused by the genus Brucella,which is the pathogenic bacteria in public health risk and occupation exposure.Therefore,rapid detection and identification of Brucella is crucial for controlling and managing the prevalence of brucellosis.In this work,matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF MS)combined with machine learning(ML)algorithms was developed to identify Brucella isolates at the species level rapidly.A total of 1440 MALDI spectral data from 59 strains of B.melitensis(23 strains of B.melitensis bv.1 and 36 strains of B.melitensis bv.3)were obtained.Four ML algorithms including support vector machine(SVM),random forest(RF),extreme gradient boosting(XGBoost),and logistic regression(LR)were compared for typing Brucella species.The area under receiver operating characteristic(ROC)curve,precision-recall ratio(PR),accuracy,specificity,and sensitivity were used to evaluate the performances of diff erent ML algorithms.These results showed that MALDI-TOF MS combined with the XGBoost algorithm is the best method for typing Brucella species with good performances,demonstrating the significant potential applications in the diagnosis,control,and epidemiology of brucellosis.
基金supported by the National Key Laboratory of Agricultural Equipment Technologysupported by the National Natural Science Foundation of China(32271979)。
文摘Detecting trace pesticide residues in food products is crucial for ensuring food safety.Terahertz technology has demonstrated significant advantages in chemical and biological sensing by utilizing the vibrational signatures inherent to molecules in the terahertz spectrum and leveraging the amplified electric fields facilitated by metamaterials.In this work,we introduce a novel method for imidacloprid(IMI)pesticide residue detection using the rod-shaped terahertz metamaterial(RSTM)with a composite interface of gold and conductive polymer polyaniline(PANI).The core mechanism of this method relies on the binding of IMI to PANI,which alters the resonance intensity and frequency of the Au-PANI-RSTM.Specifically,the RSTM parameters are determined using computer simulation technology(CST),and the RSTM structure is engraved on the Au-PANI surface using laser direct writing technology.Further characterization using mid-infrared spectroscopy(MIR)and X-ray photoelectron spectroscopy(XPS)techniques reveals that the stable bonding between PANI and IMI is facilitated by hydrogen bonding and covalent bonding.The detection limit of Au-PANI-RSTM deposited with 20 segments for IMI is 0.46 ppm,which complies with the maximum residue limit for IMI stipulated in the Chinese National Standard.
基金financially supported by ANID-FONDECYT No.1201978DICYT Asociativo USACH 022242TN_DAS。
文摘A rapid and effective analytical method was developed for the detection of triclosan in wastewater samples using a hydrophobic deep eutectic solvent thymol-lidocaine(Thy-Lid,molar ratio of 1:1)and dispersive liquid-liquid microextraction(DLLME).The analyte was determined by high-performance liquid chromatography with a photodiode array detector(HPLC-PDA),obtaining a detection limit of 0.38μg/L,a recovery rate of 99%,and an enrichment factor of the analyte in the water of 80.A factorial design was used to optimize the analytical signal to improve the time and reduce the cost of the method.Combining this chemometric optimization tool with a green solvent and DLLME allows for obtaining an analytical methodology aligned with the principles of green analytical chemistry,enabling the inexpensive,selective,and rapid analysis of triclosan in real wastewater.
基金supported by the Natural Science Foundation of Anhui Province(2308085QH303)Anhui Provincial Health Research Program(AHWJ2022b113)Basic and Clinical Collaboration Program of Anhui Medical University(2022sfy004)。
文摘The hybridization chain reaction(HCR)is a widely used nucleic acid amplification technique that is essential for gene expression analysis and disease diagnosis.Despite its inherent stability,traditional HCR often suffers from low detection efficiency,which necessitates the use of supplementary molecular technologies to enhance its performance for detecting trace samples.Drawing insights from confinement theory,we have proposed a novel cruciform DNA scaffold-based HCR reaction system(C-HCR).In our approach,the DNA cruciform is assembled with the initiating probes of the HCR reaction through specific binding between adenine-rich and thymine-rich regions.This assembly with derived chains does not interfere with the HCR process.When a target is present,traditional HCR reactions yield long-chain linear products.However,the incorporation of the DNA cruciform in C-HCR leads to the formation of network-like products,which create favorable conditions for efficient molecular collisions and,in turn,promote high detection efficiency within the system.We utilized miR-21 and miR-27a as model targets to validate our design concept.Our results revealed that the miRNA-specific HCR system for miR-21 and miR-27a achieved significant increases in detection efficiency of 27.8%and 50%,respectively,demonstrating the feasibility and versatility of our design.This study offers a new strategy for enzyme-free amplification systems.
基金supported by the National Natural Science Foundation of China(21507041,21677060)the Zhejiang Province Public Welfare Technology Application Research Project(LGF21B050004)+1 种基金Scientific Research Fund of Zhejiang Provincial Education Department(Y202352065)Jiaxing Municipal Public Welfare Research Project(2022AY10015)。
文摘A novel composite of aptamer-based Ti_(3)C_(2)T_(x)and molecularly imprinted polymer(Apt-Ti_(3)C_(2)T_(x)-MIP)with double recognition property was prepared for sensitive electrochemical detection of ofloxacin(OFL).First,Ti_(3)C_(2)T_(x)@SiO_(2)was synthesized using multi-layer Ti_(3)C_(2)T_(x)and tetraethyl orthosilicate(TEOS)in alkaline conditions.Amino Ti_(3)C_(2)T_(x)@SiO_(2)was then prepared through Ti_(3)C_(2)T_(x)@SiO_(2)in the presence of(3-aminopropyl)triethoxysilane.Carboxyl OFL aptamers were then grafted onto amino Ti_(3)C_(2)T_(x)@SiO_(2)to prepare aptamer-modified Ti_(3)C_(2)T_(x)@SiO_(2).A novel composite of Apt-Ti_(3)C_(2)T_(x)-MIP was prepared with sol–gel method in the presence of Ti_(3)C_(2)T_(x)@SiO_(2)-Apt-OFL and TEOS.The Apt-Ti_(3)C_(2)T_(x)-MIP sensor exhibited double recognition for OFL because of aptamer specificity and imprinted binding sites.The electrochemical response of Apt-Ti_(3)C_(2)T_(x)-MIP sensor for OFL was 2.29 and 2.75 times that of Apt-Ti_(3)C_(2)T_(x)-NIP and Ti_(3)C_(2)T_(x)-MIP sensors,respectively,demonstrating the double recognition of Apt-Ti_(3)C_(2)T_(x)-MIP for OFL.The Apt-Ti_(3)C_(2)T_(x)-MIP sensor with double recognition displayed a linear peak current to OFL centration from 0.025 to 10μM with a detection limit of 10 nM.The Apt-Ti_(3)C_(2)T_(x)-MIP sensor had excellent selectivity for OFL and has been successfully applied to the detection of OFL in a wastewater sample.
基金supported by the Open Foundation,Key Laboratory of Forensic Marks,Ministry of Public Security of China(2021FMKFKT04)the National Natural Science Foundation of China(22176221)Central Public-interest Scientific Institution Basal Research Fund(CAFS 2024XT09)。
文摘Fluorescent nanoparticles offer promising applications for bioimaging due to their exceptional attributes,including heightened fluorescence brightness and prolonged photo-stability,surpassing those of traditional fluorescent dyes.However,the selection of suitable materials and surface functionalization strategies for the synthesis of efficient fluorescent nanoparticles remains a significant challenge in this field.Here,we report a facile synthesis method of fluorescent nanoparticles,which is rationally designed by coating polydopamine(PDA)on eutectic Gallium-Indium(EGaIn,a liquid metal(LM))under ultrasonic waves to prepare the fluorescent PDA/LM nanoparticles.The fluorescence intensity of the PDA/LM nanoparticles is eightfold greater than that of the pristine PDA nanoparticles and can be quenched by Pb^(2+).It demonstrates that the PDA/LM nanoparticles exhibit superior analytical performance for Pb^(2+)over a linear range from 10 to 100μg/L,with a detection limit of 3μg/L.This probe can be used to detect Pb^(2+)in different vessels.
基金funded by by National Natural Science Foundation of China (21890741,21827812)。
文摘Traditional fluorescent emitters cannot eff ectively utilize triplet excitons owing to the spin statistical limitation, thus their electrochemiluminescence(ECL) efficiency(Φ_(ECL)) is relatively low. Improving the utilization efficiency of triplet excitons is of great significance for developing efficient luminescent materials. Here we designed a hot exciton molecule(NZ2TPA) containing highly efficient chromophore naphthothiadiazole as an electron acceptor and triphenylamine(TPA) with aggregation induced emission(AIE) property as the strong electron donor to synthesize an ECL nanoemitter-NZ2TPA nanoparticles(NT NPs). The hybridized local and charge-transfer(HLCT) excited state of NZ2TPA achieved a high exciton utilization through the reverse intersystem crossing from higher triplet states( h RISC). The combination of HLCT and AIE characteristics endowed NT NPs with superior ΦECLover other nanoemitters, which provided an excellent material for the design of highly sensitive ECL biosensors. Using alkaline phosphatase(ALP) as an analyte model, a “signal-on” ECL biosensing approach was constructed by combining the quenching of manganese dioxide nanosheets(MnO_(2)NSs) on ECL emission of NT NPs and the reduction of MnO_(2)by ascorbic acid produced from ALP-catalyzed dephosphorylation, which showed a detectable range of 0.004-400 U/L with a detection limit of 0.57 mU/L. The excellent performance demonstrated the immense potential of organic nanomaterials through combining HLCT and AIE properties to improve ΦECL.
基金supported by the National Natural Science Foundation of China(22176210,22350410393,42376188,22376216,22404143)the Shandong Provincial Natural Science Foundation(ZR2024QB032,ZR2024MB066)the Major Innovation Fund of Shandong Province(2021ZDSYS23)。
文摘New pollutants(NPs)are characterized by their concealment,persistence,and bioaccumulation and have emerged as a major concern in the international community.The screening and identification of NPs are fundamental prerequisites for research into their environmental behavior,toxicological eff ects,remediation,and other related areas.Molecularly imprinted ratiometric fluorescence(MI-RFL)sensors,known for their high selectivity,sensitivity,rapidity,and convenience,have garnered significant attention in the analytical detection of NPs.This review focuses on three major categories of NPs,persistent organic pollutants,environmental endocrine disruptors,and antibiotics,and examines recent advancements in MI-RFL sensors for the screening,identification,and detection of NPs since 2018.We briefly outline the preparation technologies and strategies for molecularly imprinted polymers(MIPs)and the potential detection principles of these sensors.Additionally,we highlight the fluorescence sources and construction strategies of MI-RFL sensors.The review also summarizes wellconstructed multiple MI-RFL sensors for the rapid detection of various NPs residues in complicated matrices,providing typical application examples in the fields of food safety,environmental monitoring,and biological medicine.Finally,we propose future perspectives on the construction and applications of MI-RFL sensors for detecting NPs.
基金supported by the NationalNatural Science Foundation of China(21927808,21974078,21727813,and 22227803)the China Ministry of Science and Technologyunder Contract(2022YFF0710200)。
文摘Due to the important role of vitamin D in metabolism,developing a method for rapid and high-throughput analysis of vitamin D and its metabolites is crucial.However,the current clinical diagnostic methods have the disadvantage of complicated operating procedures.In the present study,a technique combining immunocapture with mass spectrometry for rapidly detecting of 25-hydroxyvitamin D_(3)in serum was developed.This method employs an antibody–antigen reaction to specifically enrich 25-hydroxyvitamin D_(3)and remove complex interfering substances.Qualitative and quantitative analysis of 25-hydroxyvitamin D_(3)was achieved by nano-electrospray ionization-mass spectrometry(nano-ESI–MS).The method exhibited good linearity in the range of 1–100 ng/mL with satisfactory recovery and repeatability.The proposed method is promising for high-throughput and rapid analysis of small molecules with mass spectrometry.And it can potentially be combined with portable mass spectrometers to meet the requirements of point-of-care detection.
基金West Texas A&M University Killgore Research Grant。
文摘Several organic polymers and sol-gel derived porous silica were investigated as cladding material of a fused silica optical fi ber as well as a solid phase microextraction (SPME) material in an eff ort to develop an evanescent wave optical fi ber chemical sensor (EW-OFCS) for detecting acetylsalicylic acid (ASA) in aqueous sample solutions.A dip-coating method was adopted for coating a polymer on the fi ber core surface of a bent optical fi ber probe (BOFP) as a cladding/SPME membrane.Among the polymers investigated,it was found that cellulose triacetate (CTA) can function as a SPME material for concentrating ASA from aqueous sample solution into CTA membrane coated on BOFP surface.The ASA concentrated into the CTA membrane was detected by passing a light beam through the BOFP and detecting the fi ber optic EW absorption signal at ASA’s intrinsic peak absorption wavelength (310 nm).No chemical reaction was involved in the developed sensor and no chemical reagent is needed in using the sensor for detecting ASA in an aqueous sample solution.The sensor response is reversible because SPME is a reversible process.This SPME-EW-OFCS achieved a detection limit of 0.72μg/mL for detecting ASA in aqueous sample solutions.The sensor has been used for analyzing ASA in pharmaceutical Aspirin products,and obtained analytical results agree well with a conventional UV/Vis absorption spectrometric method.
基金Open access funding provided by FCT|FCCN(b-on)financial support from Fundacao para a Ciência e Tecnologia and Ministério da Ciência,Tecnologia e Ensino Superior(FCT/MCTES)by projects UID/50006-Laboratório Associado para a Química Verde-Tecnologias e Processos Limpos,UIDB/04378/2020(UCIBIO),and LA/P/0140/2020(i4HB)through PT national funds,as well as by project EXPL/MED-QUI/0815/2021。
文摘This study aimed to identify new compounds capable of decreasing pancreatic lipase(PL)catalytic activity.A panel of structurally related chalcones with hydroxy and chloro substituents was chosen,and their inhibitory eff ects on the targeted enzyme were assessed.This work also optimized the conditions for UV/Vis spectrophotometric and fluorimetric microanalysis systems and,whenever possible,a structure–activity relationship analysis was performed.The obtained results showed the eff ectiveness of both methodologies in assessing the inhibition of PL catalytic activity.Some of the tested chalcones exhibited notable inhibitory eff ects on PL activity.Remarkably,the presence of hydroxy or chloro substituents appears to enhance the observed inhibitory activities of these compounds.
文摘A simplistic and novel electrochemical sensor for selectively detecting the essential amino acid tryptophan in dietary supplements was fabricated on a pencil graphite electrode modified with a tryptophan-based dipeptide.The dipeptide was synthesized using common synthetic strategy for amino acid couplings.The modified electrode was characterized by scanning electron microscopy,impedance spectroscopy,cyclic voltammetry,and infrared spectroscopy.Differential pulse voltammetry was used to study the electrochemical response of the fabricated electrode to tryptophan in dietary supplements.Under the optimized experimental conditions,a distinct oxidation peak at+0.671 V corresponding to tryptophan was noticed in differential pulse voltammetry,which indicated the detection of tryptophan by the fabricated electrode.The oxidation peak current for tryptophan was found to be linear within a concentration range of 10–350μM with a lower detection limit of 1.2μM,and the sensitivity of the fabricated electrode was 6.9μA/μM/cm^(2).Excellent selectivity,permissible reproducibility,and good stability of the sensor make it undoubtedly suitable for determining tryptophan in dietary supplements.
文摘Trimethylamine N-oxide(TMAO),a small microbial metabolite,is bioactive and closely related to cardiovascular diseases(CVD)and chronic kidney diseases.Studying functions of TMAO calls for convenient and accurate methods to quantify TMAO.Herein,we proposed two novel chemiluminescent(CL)probes by grafting halogenated propyl ether to Schaap's dioxetane skeleton.The detection is based on a unique oxidation reaction using TMAO as the oxidant,which uncages the luminescent scaff old to emit green luminescence.Reasonable selectivity and sensitivity were achieved on the assay with iodinated probe CLTI.An excellent linear correlation(R^(2)=0.997)of CL intensity versus TMAO concentration was found at low micromolar ranges(5-50μM).The quantification of TMAO in partial marine fishes,as well as the isolated organs and tissues of Sequoia fishes,has been realized.This study presented probably the first CL method for TMAO determination.
基金financially supported by the National Natural Science Foundation of China(22104010)Shandong Provincial Natural Science Foundation of China(ZR2021QB141)+2 种基金Qingchuang Science and Technology Plan of Shandong Province(2021KJ054)Talent Incubation Project of Dezhou University(2019xjrc211,2019xjrc204 and SYJS22013)Dezhou Science and Technology Plan Project(2022dzkj057 and 2022dzkj058)。
文摘The antimony(Sb)electrode,despite its prevalent use for pH detection in complex environments,suffers from severe potential drift due to poor corrosion resistance,thereby impeding long-term or online applications.Intermetallic compounds show excellent resistance to corrosion and oxidation,presenting a promising avenue for improving the stability of the Sb electrode.Therefore,we fabricate an intermetallic compound-doped Sb electrode by adding various cobalt(Co)contents to improve the stability of the Sb electrode without compromising the inherent pH response.It's observed that the alloy electrode exhibits a significant reduction in surface roughness,corrosion product Sb_(2)O_(3)content,cracks,and Sb exfoliation compared to the pure Sb electrode after the electrochemical tests,and the effect becomes more pronounced as the Co content increases.The electrochemical tests further reveal that the alloy electrode exhibits better corrosion resistance than the pure Sb in various solutions,with the alloy electrode containing 80 at%Sb showing the highest corrosion resistance.Moreover,the alloy electrode containing 80 at%Sb also shows excellent sensitivity and anti-interference ability,high accuracy and reproducibility,low hysteresis,and better long-term stability,especially in seawater.These findings suggest that inexpensive Co doping significantly enhances corrosion resistance,thereby reducing electrode surface alterations and eventually improving the potential stability of pure Sb electrodes without affecting the inherent pH response.Furthermore,the obtained results provide an experimental basis for the long-term operation of the alloy pH electrode in complex environments such as seawater without frequent maintenance.
基金supported by the National Natural Science Foundation of China(82274223)National Drug Standard Improvement Project(2023Z002)。
文摘Agarwood is a resinous wood produced by plants of the genus Aquilaria in the Thymelaeaceae family after being injured.The wide distribution of origins and the complexity of formation have led to various species of agarwood.The preciousness,universality of application and scarcity of resources bring difficulties to the quality control of agarwood,the in-situ ionization technique shows great potential in the rapid and accurate identification of valuable herbal medicines.In this paper,based on the combination of paper capillary spray and miniature mass spectrometry,different kinds of agarwood and counterfeits were directly added onto the chromatography paper,the active ingredients were extracted by solvent and then carried out by the portable miniature mass spectrometry,which could be implemented to perform an effective and on-site analysis,and the whole process only took about 1 min.Characteristic highly oxidized 2-(2-phenylethyl)chromones and flindersia-type 2-(2-phenylethyl)chromones were detected in authentic agarwood,and other characteristic flindersia-type 2-(2-phenylethyl)chromones were detected in authentic Kynam agarwood(special variety of agarwood),while the above characteristic components were not detected in counterfeits.Furthermore,an artificial intelligence model based on random forest algorithm was established for automatic identification.This approach is versatile,unfettered by location or environmental constraints,making it particularly valuable in the identification of precious Chinese herbal medicines.
