Traditional Chinese medicine(TCM)has garnered significant global interest owing to its multi-component and multi-target theoretical framework and extensive therapeutic efficacy.However,the identification of quality ma...Traditional Chinese medicine(TCM)has garnered significant global interest owing to its multi-component and multi-target theoretical framework and extensive therapeutic efficacy.However,the identification of quality markers(Q-markers)remains a formidable challenge in TCM.Hence,this study aimed to integrate network pharmacology and chemometrics to identify Q-markers in Chinese patent medicine,with a focus on Huo-Luo-San(HLS)as a case study.HLS,a widely used powdered Chinese patent medicine in China,comprises a complex formula of 10 herbs,initially formulated during the Qing dynasty for treating fractures.Initially,13 components,chlorogenic acid,typhaneoside,isorhamnetin-3-O-neohesperidoside,cynaroside,notoginsenoside R_1,ginsenoside Rg_1,baicalin,berberine hydrochloride,ginsenoside Rb_1,dehydrocostus lactone,dioscin,imperatorin,and costunolide,were selected as phytochemical markers for each herb based on the Chinese Pharmacopoeia(2020 version),forming the“Herbs-Compounds-targets”network of HLS using network pharmacology.Subsequently,employing network pharmacology,the 13 HLS components were quantified using UPLC-QqQ-MS.Chromatographic conditions were optimized on a Waters Cortecs C_(18)column(2.1 mm×100 mm,1.6μm)with a gradient elution comprising 0.1%formic acid in water and acetonitrile.Analyte detection was performed in the multiple-reaction monitoring mode,and the method underwent validation for linearity,detection limit,precision,repeatability,stability,and accuracy.The validated method was then utilized to analyze the 13 components in 15 batches of HLS samples.Chemometric techniques,including hierarchical cluster analysis,principal component analysis,orthogonal partial least squares projection discriminant analysis,and box map analyses,were subsequently employed to identify the Q-markers.Ultimately,six components,baicalin,notoginsenoside R_1,berberine hydrochloride,dioscin,imperatorin,and chlorogenic acid,were selected as Q-markers for HLS.The integration of network pharmacology with chemometrics represented a novel approach for selecting Q-markers in Chinese patent medicine.展开更多
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16...Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits.展开更多
A new, simple and reliable method using HPLC-UV-ELSD was developed to generate the fingerprint of Ophiopogonis Radix. Homoisoflavonoids and steroidal saponins were determined simultaneously in a single run. A total of...A new, simple and reliable method using HPLC-UV-ELSD was developed to generate the fingerprint of Ophiopogonis Radix. Homoisoflavonoids and steroidal saponins were determined simultaneously in a single run. A total of 27 Ophiopogonis Radix samples were analyzed, and 18 reference substances were used for the identification of the common peaks. The fingerprint was further analyzed by chemometrics methods including similarity analysis （SA）, hierarchical clustering analysis （HCA） and principal component analysis （PCA）. The results indicated that the combination of chromatographic fingerprint and chemometrics analysis could be used for the geographical differentiation and quality evaluation of Ophiopognnis Radix.展开更多
The simultaneous determination of cobalt, copper and nickel using 1-（2-thiazolylazo）-2-naphthol （first figure of this article） by spectrophotometric method is a difficult problem in analytical chemistry, due to sp...The simultaneous determination of cobalt, copper and nickel using 1-（2-thiazolylazo）-2-naphthol （first figure of this article） by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By multivariate calibration methods, such as partial least squares （PLS） regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction （OSC） is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for PLS calibration of mixtures without loss of prediction capacity using spectrophotometric method. In this study, the calibration model is based on absorption spectra in the 550-750-nm range for 21 different mixtures of cobalt, copper and nickel. Calibration matrices were formed from samples containing 0.05-1.05, 0.05-1.30 and 0.05-0.80 μg·mL^-1 for cobalt, copper and nickel, respectively. The root mean square error of prediction （RMSEP） for cobalt, copper and nickel with OSC and without OSC were 0.007, 0.008, 0.011 and 0.031,0.037, 0.032 μg· mL^-1, respectively. This procedure allows the simultaneous determination of cobalt, copper and nickel in synthetic and real samples and good reliability of the determination was proved.展开更多
High performance liquid chromatographic(HPLC) fingerprints of Cassia seed,a traditional Chinese medicine(TCM),were developed by means of the chromatograms at two wavelengths of 238 and 282 nm.Then,the two data sets we...High performance liquid chromatographic(HPLC) fingerprints of Cassia seed,a traditional Chinese medicine(TCM),were developed by means of the chromatograms at two wavelengths of 238 and 282 nm.Then,the two data sets were combined into one matrix.The application of principal component analysis(PCA) for this data matrix showed that the samples were clustered into four groups in accordance with the plant sources and preparation procedures.Furthermore,partial least squares(PLS),back propagation artificial neural...展开更多
There are two source plants for the traditional Chinese medicine Murrayae Folium et Cacumen(MFC)in Chinese Pharmacopoeia,i.e.Murraya exotica L.and M.paniculata(L.)Jack.Herein,a chemical comparison of M.exotica and M.p...There are two source plants for the traditional Chinese medicine Murrayae Folium et Cacumen(MFC)in Chinese Pharmacopoeia,i.e.Murraya exotica L.and M.paniculata(L.)Jack.Herein,a chemical comparison of M.exotica and M.paniculata by high performance liquid chromatography(HPLC)fingerprint analysis coupled with chemometrics and network pharmacology was performed.The main peaks in the fingerprints were identified by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry(LC-IT-TOF-MS)and authenticated by references.The chemometrics results showed that the HPLC fingerprints of these two species were clearly divided into two categories using hierarchical cluster analysis(HCA)and principal component analysis(PCA),and a total of 13 significantly differentiated markers were screened out by orthogonal partial least squares-discriminant analysis(OPLS-DA).However,the following network pharmacology analysis showed that these discriminated markers were found to act via many common targets and metabolic pathways,indicating the possibly similar pharmacological effects and mechanisms for M.exotica and M.paniculata.The above results provide valuable evidence for the equivalent use of these two plants in clinical settings.Moreover,the chromatographic fingerprint analysis coupled with chemometrics and network pharmacology supplies an efficient approach for the comparative analysis of multi-source TCMs like MFC.展开更多
To objectively classify and evaluate the strong aroma base liquors(SABLs)of different grades,solid-phase microextraction-mass spectrometry(SPME-MS)combined with chemometrics were used.Results showed that SPME-MS combi...To objectively classify and evaluate the strong aroma base liquors(SABLs)of different grades,solid-phase microextraction-mass spectrometry(SPME-MS)combined with chemometrics were used.Results showed that SPME-MS combined with a back-propagation artificial neural network(BPANN)method yielded almost the same recognition performance compared to linear discriminant analysis(LDA)in distinguishing different grades of SABL,with 84%recognition rate for the test set.Partial least squares(PLS),successive projection algorithm partial least squares(SPA-PLS)model,and competitive adaptive reweighed samplingpartial least squares(CARS-PLS)were established for the prediction of the four esters in the SABL.CARS-PLS model showed a greater advantage in the quantitative analysis of ethyl acetate,ethyl butyrate,ethyl caproate,and ethyl lactate.These results corroborated the hypothesis that SPME-MS combined with chemometrics can effectively achieve an accurate determination of different grades of SABL and prediction performance of esters.展开更多
The interactions of carbofuran and DNA were studied using voltammetry and fluorescence spectroscopy.The formation of carbofuran-DNA makes the current peak of DNA decreased by voltammetry method.The binding number（n）...The interactions of carbofuran and DNA were studied using voltammetry and fluorescence spectroscopy.The formation of carbofuran-DNA makes the current peak of DNA decreased by voltammetry method.The binding number（n） and constant（Ka） for complex carbofuran-DNA were calculated to be 1.06±0.04 and 0.11±0.03mol^-1 L,respectively by fluorescence measurement.Chemometrics approach,such as singular value decomposition（SVD） was used to evaluate the number of spectral species in the drug-DNA binding process.And the pure spectra and concentration profiles in the kinetic system were clearly deduced by multivariate curve resolution alternating least squares（MCR-ALS） with the initial estimates by evolving factor analysis（EFA）.展开更多
The voltammetric behaviour of three 5-nitroimidazoles,metronidazole,tinidazole and ornidazole,was investigated,and a method was developed for the simultaneous determination of these compounds,based on their reduction ...The voltammetric behaviour of three 5-nitroimidazoles,metronidazole,tinidazole and ornidazole,was investigated,and a method was developed for the simultaneous determination of these compounds,based on their reduction at a hanging mercury drop electrode（HMDE） in pH 8.95 buffer with differential pulse voltammetric（DPV） approach.Well defined voltammetric waves with peak potentials of -692,-640 and -652 mV were observed for these compounds,respectively.It is difficult to determine them individually from their mixtures without preseparation,for their voltammetric peaks overlapped seriously,so the chemometrics were used to resolve the overlapped voltammogram and quantify the mixtures.The proposed method was successfully applied to the determination of three 5-nitroimidazoles in milk and honey samples.展开更多
Differential pulse stripping voltammetry method（DPSV） was applied to the determination of three herbicides, ametryn, cyanatryn, and dimethametryn. It was found that their voltammograms overlapped strongly, and it is...Differential pulse stripping voltammetry method（DPSV） was applied to the determination of three herbicides, ametryn, cyanatryn, and dimethametryn. It was found that their voltammograms overlapped strongly, and it is difficult to determine these compounds individually from their mixtures. With the aid of chemometrics, classical least squares（CLS）, principal component regression（PCR） and partial least squares（PLS）, voltammogram resolution and quantitative analysis of the synthetic mixtures of the three compounds were successfully performed. The proposed method was also applied to the analysis of some real samples with satisfactory results.展开更多
A procedure for the simultaneous kinetic spectrophotometric determination of cephalexin and trimethoprim was described. It was based on the different reaction rate of oxidation of these compounds with yellow ammonium ...A procedure for the simultaneous kinetic spectrophotometric determination of cephalexin and trimethoprim was described. It was based on the different reaction rate of oxidation of these compounds with yellow ammonium cerous （Ⅳ） sulfate in acidic medium and colorless cerous （Ⅲ） sulfate was produced. The overlapped kinetic data was quantitatively resolved by the use of chemometric methods, partial least squares （PLS）, principal component regression （PCR） and radial basis function-artificial neural network （RBF-ANN）. The proposed method was also applied to the simultaneous determination of cephalexin and trimethoprim in pharmaceutical preparation and human urine with satisfied results, which compared well with those obtained by HPLC.展开更多
In order to better control the quality of Flos Puerariae(FP),qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study.First,the fingerprint of...In order to better control the quality of Flos Puerariae(FP),qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study.First,the fingerprint of FP was developed by HPLC and the chemical markers were screened out by similarity analysis(SA),hierarchical clustering analysis(HCA),principal components analysis(PCA),and orthogonal partial least squares discriminant analysis(OPLS-DA).Next,the chemical constituents in FP were profiled and identified by HPLC coupled to Fourier transform ion cyclotron resonance mass spectrometry(HPLCFT-ICR MS).Then,the characteristic constituents in FP were quantitatively analyzed by HPLC.As a result,31 common peaks were assigned in the fingerprint and 6 of them were considered as qualitative markers.A total of 35 chemical constituents were detected by HPLC-FT-ICR MS and 16 of them were unambiguously identified by comparing retention time,UV absorption wavelength,accurate mass,and MS/MS data with those of reference standards.Subsequently,the contents of glycitin,genistin,tectoridin,glycitein,genistein,and tectorigenin in 13 batches of FP were detected,ranging from 0.4438 to 11.06 mg/g,0.955 to 1.726 mg/g,9.81 to 57.22 mg/g,3.349 to 41.60 mg/g,0.3576 to 0.989 mg/g,and 2.126 to 9.99 mg/g,respectively.In conclusion,fingerprint analysis in combination with chemometrics methods could discover chemical markers for improving the quality control standard of FP.It is expected that the strategy applied in this study will be valuable for further quality control of other traditional Chinese medicines.展开更多
A reliable method for simultaneous determination of three antibiotic drugs（levofloxacin,gatifloxacin and lomefloxacin） by differential pulse stripping voltammetry（DPSV） in Britton-Robinson buffer（pH 7.96） was pr...A reliable method for simultaneous determination of three antibiotic drugs（levofloxacin,gatifloxacin and lomefloxacin） by differential pulse stripping voltammetry（DPSV） in Britton-Robinson buffer（pH 7.96） was presented.The method is based on adsorptive accumulation of the antibacterial drugs on a hanging mercury dropping electrode（HMDE）,followed by the reduction of the adsorptive species by the technique of DPSV.Optimal conditions,the deposition time of 80 s,the deposition potential of—1250 mV,and the scan rate of 25 mV/s,were obtained.The linear concentration ranges of 0.010-0.080μg/mL were obtained for all these three antibiotic drugs,while the detection limits were 2.38,3.20 and 1.60ng/mL for levofloxacin,gatifloxacin and lomefloxacin,respectively.In this work,chemometrics methods,such as classical least squares（CLS）,partial least squares（PLS）, principle component regression（PCR） and radial basis function-artificial neural networks（RBF-ANN）,were used to quantitatively resolve the overlapping signals.It was found that PCR gave the best results with total relative prediction error（RPE_T） of 7.71%.The proposed method was applied to determine these three drugs in several commercial food samples with spiked method and yielded satisfactory recoveries.展开更多
We used both correlation and covariance-principal component analysis (PCA) to classify the same absorption-reflectance data collected from 13 different polymeric fabric materials that was obtained using Attenuated Tot...We used both correlation and covariance-principal component analysis (PCA) to classify the same absorption-reflectance data collected from 13 different polymeric fabric materials that was obtained using Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy (ATR-FTIR). The application of the two techniques, though similar, yielded results that represent different chemical properties of the polymeric substances. On one hand, correlation-PCA enabled the classification of the fabric materials according to the organic functional groups of their repeating monomer units. On the other hand, covariance-PCA was used to classify the fabric materials primarily according to their origins;natural (animal or plant) or synthetic. Hence besides major chemical functional groups of the repeat units, it appears covariance-PCA is also sensitive to other characteristic chemical (inorganic and/or organic) or biochemical material inclusions that are found in different samples. We therefore recommend the application of both covariance-PCA and correlation-PCA on datasets, whenever applicable, to enable a broader classification of spectroscopic information through data mining and exploration.展开更多
In this study, a seed origin discrimination model for Clinacanthus nutans was developed. First, 81 C. nutans samples from three seed origin locations were collected, and their Near-Infrared (NIR) spectra were obtained...In this study, a seed origin discrimination model for Clinacanthus nutans was developed. First, 81 C. nutans samples from three seed origin locations were collected, and their Near-Infrared (NIR) spectra were obtained. Next, Principal Component Analysis (PCA) was performed on the NIR spectra of the 81 C. nutans samples. Then, MSC (multiplicative scatter correction), SNV (standard normal variate), first derivative, and second derivative pre-treatments of the C. nutans spectra were performed and combined with the Support Vector Machine (SVM) algorithm for modelling and analysis. Among these methods, first-order derivative pre-treatment achieved the best SVM model effectiveness, with a training set accuracy of 93.44% (57/61) and a test set accuracy of 85.00% (17/20). In order to further improve the discrimination accuracy of the model, three optimization algorithms Grid Search (GS), Genetic Algorithm (GA), and Particle Swarm Optimization (PSO) were employed to identify the best c and g parameters for the SVM model. The results demonstrated that the PSO optimization algorithm yielded the best parameters of c = 0.8343, g = 57.8741, with corresponding model training set the accuracy of 96.36% (60/61) and test set the accuracy of 95.00% (20/21). Therefore, developing a seed origin classification model for C. nutans based on NIR spectroscopy combined with chemometrics is feasible and has the advantages of being simple, rapid, and green.展开更多
In this work,functionalized carbon nanotubes(CNTs)using two polyamine polymers,polyethyleneimine(PEI)and polyamidoamine dendrimer(PAMAM),were investigated by thermal analysis in order to address preparation strategies...In this work,functionalized carbon nanotubes(CNTs)using two polyamine polymers,polyethyleneimine(PEI)and polyamidoamine dendrimer(PAMAM),were investigated by thermal analysis in order to address preparation strategies to obtain low cytotoxic compounds with the ability to conjugate micro-RNAs and,at the same time,to transfect efficiently endothelial cells.Thermogravimetric analysis(TGA)was coupled to chemometrics as a novel analytical strategy to characterize functionalized CNTs from different preparation conditions.In particular,two starting materials were considered:very small CNTs and carboxylated CNTs(CNT-COOH)in order to examine the affinity with polymers.Chemometrics permitted to compare results from TGA and to investigate the effect of a number of factors affecting the synthesis of coated nanotubes including a different amount of involved polymer and the time required for the suspension for a satisfactory and reproducible preparation procedure.The results demonstrated the effectiveness of TGA as a tool able to address synthesis of coated CNTs to be employed as efficient drug delivery vectors in biomedical applications.展开更多
Human albumin(HA)is a very important blood product which requires strict quality controlstrategy.Acid precipitation is a key step which has a great effect on the quality of final product.Therefore,a new method based o...Human albumin(HA)is a very important blood product which requires strict quality controlstrategy.Acid precipitation is a key step which has a great effect on the quality of final product.Therefore,a new method based on quality by design(QbD)was proposed to investigate thefeasibility of realizing online quality control with the help of near infrared spectroscopy(NIRS)and chemometrics.The pH value is the critical process parameter(CPP)in acid precipitationprocess,which is used as the end-point indicator.Six batches,a total of 74 samples of acidprecipitation process,were simulated in our lab.Four batches were selected randomly as cali-bration set and remaining two batches as validation set.Then,the analysis based on materialinformation and three dfferent variable selection methods,including interval partial least squaresregression(iPLS),competitive adaptive reweighted sampling(CARS)and correlation coeficient(CC)were compared for eliminating irrelevant variables,Fimally,iPLS was used for variablesselection.The quantitative model was built up by partial least squares regression(PLSR).Thevalues of determination coeficients(R^(2)_(C) and R^(2)_(P)),root mean squares error of prediction(RMSEP),root mean squares error of calibration(RMSEC)and root mean squared error of crossvalidation(RMSECV)were 0.969,0.953,0.0496,0.0695 and 0.0826,respectively.The paired t test and repeatability test showed that the model had good prediction ability and stability.The results indicated that PLSR model could give accurate measurement of the pH value.展开更多
Some aspects of the fundamental problems of chemometrics are reviewed based on the research work undertaken in this laboratory. The topics touched upon Include analytical information theory, experimental design and op...Some aspects of the fundamental problems of chemometrics are reviewed based on the research work undertaken in this laboratory. The topics touched upon Include analytical information theory, experimental design and optimization, sampling, analytical detection theory, calibration, signal processing, chemical pattern recognition, quantitative structure-activity relationships, digital simulation, and teaching chemometrics as a chemical discipline.展开更多
The goal of this study was to use Fourier transform mid-infrared （FTIR） spectroscopy for discrimination of samples of pods and seeds of carob from three Moroccan regions. The origin of samples Pods and seeds of caro...The goal of this study was to use Fourier transform mid-infrared （FTIR） spectroscopy for discrimination of samples of pods and seeds of carob from three Moroccan regions. The origin of samples Pods and seeds of carob could be distinguished from their IR spectra and this measurement was used for discriminate analysis. A multivariate analysis procedure based on the combined use of Hierarchical Cluster Aanalysis （HCA） and Partial Least Squares-Discriminant Analysis （PLS-DA） was tested and provided good classification results. Three distinctive clusters were recognised, related to the three Moroccan regions. Afterwards, PLS-DA was used for the discrimination and classification of the origin of the various Pods and seeds of carob samples. The results demonstrated that the combined use of FTIR and chemometric analysis （cluster analysis and discrimination by PLS- DA） can be used to rapidly and simply determine the origin of carob pulpe samples.展开更多
基金The Subject of Fujian Province Science and Technology Hall of China(Grant No.2022J01867)National Key R&D Program of China(Grant No.2019YFC1710505)School Management Project of Fujian University of Traditional Chinese Medicine University(Grant No.X2021001 and No.XJC202301)。
文摘Traditional Chinese medicine(TCM)has garnered significant global interest owing to its multi-component and multi-target theoretical framework and extensive therapeutic efficacy.However,the identification of quality markers(Q-markers)remains a formidable challenge in TCM.Hence,this study aimed to integrate network pharmacology and chemometrics to identify Q-markers in Chinese patent medicine,with a focus on Huo-Luo-San(HLS)as a case study.HLS,a widely used powdered Chinese patent medicine in China,comprises a complex formula of 10 herbs,initially formulated during the Qing dynasty for treating fractures.Initially,13 components,chlorogenic acid,typhaneoside,isorhamnetin-3-O-neohesperidoside,cynaroside,notoginsenoside R_1,ginsenoside Rg_1,baicalin,berberine hydrochloride,ginsenoside Rb_1,dehydrocostus lactone,dioscin,imperatorin,and costunolide,were selected as phytochemical markers for each herb based on the Chinese Pharmacopoeia(2020 version),forming the“Herbs-Compounds-targets”network of HLS using network pharmacology.Subsequently,employing network pharmacology,the 13 HLS components were quantified using UPLC-QqQ-MS.Chromatographic conditions were optimized on a Waters Cortecs C_(18)column(2.1 mm×100 mm,1.6μm)with a gradient elution comprising 0.1%formic acid in water and acetonitrile.Analyte detection was performed in the multiple-reaction monitoring mode,and the method underwent validation for linearity,detection limit,precision,repeatability,stability,and accuracy.The validated method was then utilized to analyze the 13 components in 15 batches of HLS samples.Chemometric techniques,including hierarchical cluster analysis,principal component analysis,orthogonal partial least squares projection discriminant analysis,and box map analyses,were subsequently employed to identify the Q-markers.Ultimately,six components,baicalin,notoginsenoside R_1,berberine hydrochloride,dioscin,imperatorin,and chlorogenic acid,were selected as Q-markers for HLS.The integration of network pharmacology with chemometrics represented a novel approach for selecting Q-markers in Chinese patent medicine.
基金This work was supported by the Scientific Research Foundation for High Level Talents of Qingdao Agricultural University,China(665-1120015)the National Program for Quality and Safety Risk Assessment of Agricultural Products of China(GJFP2019011)the National Natural Science Foundation of China(42207017).
文摘Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits.
基金National Key Technology R&D Program"New Drug Innovation" of China (Grant No. 2012ZX09304-005,2012ZX09301002-002-002)
文摘A new, simple and reliable method using HPLC-UV-ELSD was developed to generate the fingerprint of Ophiopogonis Radix. Homoisoflavonoids and steroidal saponins were determined simultaneously in a single run. A total of 27 Ophiopogonis Radix samples were analyzed, and 18 reference substances were used for the identification of the common peaks. The fingerprint was further analyzed by chemometrics methods including similarity analysis （SA）, hierarchical clustering analysis （HCA） and principal component analysis （PCA）. The results indicated that the combination of chromatographic fingerprint and chemometrics analysis could be used for the geographical differentiation and quality evaluation of Ophiopognnis Radix.
文摘The simultaneous determination of cobalt, copper and nickel using 1-（2-thiazolylazo）-2-naphthol （first figure of this article） by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By multivariate calibration methods, such as partial least squares （PLS） regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction （OSC） is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for PLS calibration of mixtures without loss of prediction capacity using spectrophotometric method. In this study, the calibration model is based on absorption spectra in the 550-750-nm range for 21 different mixtures of cobalt, copper and nickel. Calibration matrices were formed from samples containing 0.05-1.05, 0.05-1.30 and 0.05-0.80 μg·mL^-1 for cobalt, copper and nickel, respectively. The root mean square error of prediction （RMSEP） for cobalt, copper and nickel with OSC and without OSC were 0.007, 0.008, 0.011 and 0.031,0.037, 0.032 μg· mL^-1, respectively. This procedure allows the simultaneous determination of cobalt, copper and nickel in synthetic and real samples and good reliability of the determination was proved.
基金the financial support for this study by the National Natural Science Foundation of China(No.NSFC20562009)the Jiangxi Province Natural Science Foundation(No.JXNSF0620041)the State Key Laboratory of Food Science and Technology of Nanchang University(Nos.SKLF-MB200807 and SKLF-TS200819)
文摘High performance liquid chromatographic(HPLC) fingerprints of Cassia seed,a traditional Chinese medicine(TCM),were developed by means of the chromatograms at two wavelengths of 238 and 282 nm.Then,the two data sets were combined into one matrix.The application of principal component analysis(PCA) for this data matrix showed that the samples were clustered into four groups in accordance with the plant sources and preparation procedures.Furthermore,partial least squares(PLS),back propagation artificial neural...
基金supported by the National Natural Sciences Foundation of China(Nos.81773864,81973199,and81473106)the National Key Research and Development Project(No.2019YFC1711000)。
文摘There are two source plants for the traditional Chinese medicine Murrayae Folium et Cacumen(MFC)in Chinese Pharmacopoeia,i.e.Murraya exotica L.and M.paniculata(L.)Jack.Herein,a chemical comparison of M.exotica and M.paniculata by high performance liquid chromatography(HPLC)fingerprint analysis coupled with chemometrics and network pharmacology was performed.The main peaks in the fingerprints were identified by liquid chromatography coupled with ion trap/time-of-flight mass spectrometry(LC-IT-TOF-MS)and authenticated by references.The chemometrics results showed that the HPLC fingerprints of these two species were clearly divided into two categories using hierarchical cluster analysis(HCA)and principal component analysis(PCA),and a total of 13 significantly differentiated markers were screened out by orthogonal partial least squares-discriminant analysis(OPLS-DA).However,the following network pharmacology analysis showed that these discriminated markers were found to act via many common targets and metabolic pathways,indicating the possibly similar pharmacological effects and mechanisms for M.exotica and M.paniculata.The above results provide valuable evidence for the equivalent use of these two plants in clinical settings.Moreover,the chromatographic fingerprint analysis coupled with chemometrics and network pharmacology supplies an efficient approach for the comparative analysis of multi-source TCMs like MFC.
基金The study was supported by the Key Research and Development Program of Jiangsu Province(BE2020312)National Natural Science Foundation of China(31671844)+2 种基金Open Project of National Engineering Laboratory for Agri-product Quality Traceability(AQT-2019-YB7)Science Foundation for Postdoctoral in Jiangsu Province(1501100C)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘To objectively classify and evaluate the strong aroma base liquors(SABLs)of different grades,solid-phase microextraction-mass spectrometry(SPME-MS)combined with chemometrics were used.Results showed that SPME-MS combined with a back-propagation artificial neural network(BPANN)method yielded almost the same recognition performance compared to linear discriminant analysis(LDA)in distinguishing different grades of SABL,with 84%recognition rate for the test set.Partial least squares(PLS),successive projection algorithm partial least squares(SPA-PLS)model,and competitive adaptive reweighed samplingpartial least squares(CARS-PLS)were established for the prediction of the four esters in the SABL.CARS-PLS model showed a greater advantage in the quantitative analysis of ethyl acetate,ethyl butyrate,ethyl caproate,and ethyl lactate.These results corroborated the hypothesis that SPME-MS combined with chemometrics can effectively achieve an accurate determination of different grades of SABL and prediction performance of esters.
基金the financial support by the State Key Laboratory of Food Science and Technology of Nanchang University(Nos.SKLF-MB-200807 and SKLF-TS-200819)
文摘The interactions of carbofuran and DNA were studied using voltammetry and fluorescence spectroscopy.The formation of carbofuran-DNA makes the current peak of DNA decreased by voltammetry method.The binding number（n） and constant（Ka） for complex carbofuran-DNA were calculated to be 1.06±0.04 and 0.11±0.03mol^-1 L,respectively by fluorescence measurement.Chemometrics approach,such as singular value decomposition（SVD） was used to evaluate the number of spectral species in the drug-DNA binding process.And the pure spectra and concentration profiles in the kinetic system were clearly deduced by multivariate curve resolution alternating least squares（MCR-ALS） with the initial estimates by evolving factor analysis（EFA）.
文摘The voltammetric behaviour of three 5-nitroimidazoles,metronidazole,tinidazole and ornidazole,was investigated,and a method was developed for the simultaneous determination of these compounds,based on their reduction at a hanging mercury drop electrode（HMDE） in pH 8.95 buffer with differential pulse voltammetric（DPV） approach.Well defined voltammetric waves with peak potentials of -692,-640 and -652 mV were observed for these compounds,respectively.It is difficult to determine them individually from their mixtures without preseparation,for their voltammetric peaks overlapped seriously,so the chemometrics were used to resolve the overlapped voltammogram and quantify the mixtures.The proposed method was successfully applied to the determination of three 5-nitroimidazoles in milk and honey samples.
基金Supported by the National Natural Science Foundation of China(No. 20562009)the Natural Science Foundation of Jiangxi Province, China(No. 0620041)+1 种基金the State Key Laboratory of the Chemo/Biosensing and Chemometrics of Hunan University, Chi-na(No. 2005-22)the Program for Changjiang Scholars and Innovative Research Team in Universities of China(No. IRT0540).
文摘Differential pulse stripping voltammetry method（DPSV） was applied to the determination of three herbicides, ametryn, cyanatryn, and dimethametryn. It was found that their voltammograms overlapped strongly, and it is difficult to determine these compounds individually from their mixtures. With the aid of chemometrics, classical least squares（CLS）, principal component regression（PCR） and partial least squares（PLS）, voltammogram resolution and quantitative analysis of the synthetic mixtures of the three compounds were successfully performed. The proposed method was also applied to the analysis of some real samples with satisfactory results.
基金the financial support from the National Natural Science Foundation of China(No.20562009)the Natural Science Foundation of Jiangxi Province(No.0620041)+1 种基金the State Key Laboratory of the Chemo/Biosensing and Chemometrics of Hunan University(No.2005-22)the program for Changjiang Scholars and Innovative Research Team in Universities(No.IRT0540).
文摘A procedure for the simultaneous kinetic spectrophotometric determination of cephalexin and trimethoprim was described. It was based on the different reaction rate of oxidation of these compounds with yellow ammonium cerous （Ⅳ） sulfate in acidic medium and colorless cerous （Ⅲ） sulfate was produced. The overlapped kinetic data was quantitatively resolved by the use of chemometric methods, partial least squares （PLS）, principal component regression （PCR） and radial basis function-artificial neural network （RBF-ANN）. The proposed method was also applied to the simultaneous determination of cephalexin and trimethoprim in pharmaceutical preparation and human urine with satisfied results, which compared well with those obtained by HPLC.
基金supported by Liaoning Province Natural Science Foundation(Grant No.:2021-MS-220).
文摘In order to better control the quality of Flos Puerariae(FP),qualitative and quantitative analyses were initially performed by using chemical fingerprint and chemometrics methods in this study.First,the fingerprint of FP was developed by HPLC and the chemical markers were screened out by similarity analysis(SA),hierarchical clustering analysis(HCA),principal components analysis(PCA),and orthogonal partial least squares discriminant analysis(OPLS-DA).Next,the chemical constituents in FP were profiled and identified by HPLC coupled to Fourier transform ion cyclotron resonance mass spectrometry(HPLCFT-ICR MS).Then,the characteristic constituents in FP were quantitatively analyzed by HPLC.As a result,31 common peaks were assigned in the fingerprint and 6 of them were considered as qualitative markers.A total of 35 chemical constituents were detected by HPLC-FT-ICR MS and 16 of them were unambiguously identified by comparing retention time,UV absorption wavelength,accurate mass,and MS/MS data with those of reference standards.Subsequently,the contents of glycitin,genistin,tectoridin,glycitein,genistein,and tectorigenin in 13 batches of FP were detected,ranging from 0.4438 to 11.06 mg/g,0.955 to 1.726 mg/g,9.81 to 57.22 mg/g,3.349 to 41.60 mg/g,0.3576 to 0.989 mg/g,and 2.126 to 9.99 mg/g,respectively.In conclusion,fingerprint analysis in combination with chemometrics methods could discover chemical markers for improving the quality control standard of FP.It is expected that the strategy applied in this study will be valuable for further quality control of other traditional Chinese medicines.
基金support by the National Natural Science Foundation of China (No21065007)the State Key Laboratory of Food Science and Technology of Nanchang University(SKLF-MB-201002 and SKLF-TS-200919)
文摘A reliable method for simultaneous determination of three antibiotic drugs（levofloxacin,gatifloxacin and lomefloxacin） by differential pulse stripping voltammetry（DPSV） in Britton-Robinson buffer（pH 7.96） was presented.The method is based on adsorptive accumulation of the antibacterial drugs on a hanging mercury dropping electrode（HMDE）,followed by the reduction of the adsorptive species by the technique of DPSV.Optimal conditions,the deposition time of 80 s,the deposition potential of—1250 mV,and the scan rate of 25 mV/s,were obtained.The linear concentration ranges of 0.010-0.080μg/mL were obtained for all these three antibiotic drugs,while the detection limits were 2.38,3.20 and 1.60ng/mL for levofloxacin,gatifloxacin and lomefloxacin,respectively.In this work,chemometrics methods,such as classical least squares（CLS）,partial least squares（PLS）, principle component regression（PCR） and radial basis function-artificial neural networks（RBF-ANN）,were used to quantitatively resolve the overlapping signals.It was found that PCR gave the best results with total relative prediction error（RPE_T） of 7.71%.The proposed method was applied to determine these three drugs in several commercial food samples with spiked method and yielded satisfactory recoveries.
文摘We used both correlation and covariance-principal component analysis (PCA) to classify the same absorption-reflectance data collected from 13 different polymeric fabric materials that was obtained using Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy (ATR-FTIR). The application of the two techniques, though similar, yielded results that represent different chemical properties of the polymeric substances. On one hand, correlation-PCA enabled the classification of the fabric materials according to the organic functional groups of their repeating monomer units. On the other hand, covariance-PCA was used to classify the fabric materials primarily according to their origins;natural (animal or plant) or synthetic. Hence besides major chemical functional groups of the repeat units, it appears covariance-PCA is also sensitive to other characteristic chemical (inorganic and/or organic) or biochemical material inclusions that are found in different samples. We therefore recommend the application of both covariance-PCA and correlation-PCA on datasets, whenever applicable, to enable a broader classification of spectroscopic information through data mining and exploration.
文摘In this study, a seed origin discrimination model for Clinacanthus nutans was developed. First, 81 C. nutans samples from three seed origin locations were collected, and their Near-Infrared (NIR) spectra were obtained. Next, Principal Component Analysis (PCA) was performed on the NIR spectra of the 81 C. nutans samples. Then, MSC (multiplicative scatter correction), SNV (standard normal variate), first derivative, and second derivative pre-treatments of the C. nutans spectra were performed and combined with the Support Vector Machine (SVM) algorithm for modelling and analysis. Among these methods, first-order derivative pre-treatment achieved the best SVM model effectiveness, with a training set accuracy of 93.44% (57/61) and a test set accuracy of 85.00% (17/20). In order to further improve the discrimination accuracy of the model, three optimization algorithms Grid Search (GS), Genetic Algorithm (GA), and Particle Swarm Optimization (PSO) were employed to identify the best c and g parameters for the SVM model. The results demonstrated that the PSO optimization algorithm yielded the best parameters of c = 0.8343, g = 57.8741, with corresponding model training set the accuracy of 96.36% (60/61) and test set the accuracy of 95.00% (20/21). Therefore, developing a seed origin classification model for C. nutans based on NIR spectroscopy combined with chemometrics is feasible and has the advantages of being simple, rapid, and green.
基金The authors thank the Italian Ministry of Health for funding this research(Progetto Ricerca Finalizzata PE-2011-02347026).
文摘In this work,functionalized carbon nanotubes(CNTs)using two polyamine polymers,polyethyleneimine(PEI)and polyamidoamine dendrimer(PAMAM),were investigated by thermal analysis in order to address preparation strategies to obtain low cytotoxic compounds with the ability to conjugate micro-RNAs and,at the same time,to transfect efficiently endothelial cells.Thermogravimetric analysis(TGA)was coupled to chemometrics as a novel analytical strategy to characterize functionalized CNTs from different preparation conditions.In particular,two starting materials were considered:very small CNTs and carboxylated CNTs(CNT-COOH)in order to examine the affinity with polymers.Chemometrics permitted to compare results from TGA and to investigate the effect of a number of factors affecting the synthesis of coated nanotubes including a different amount of involved polymer and the time required for the suspension for a satisfactory and reproducible preparation procedure.The results demonstrated the effectiveness of TGA as a tool able to address synthesis of coated CNTs to be employed as efficient drug delivery vectors in biomedical applications.
基金support of the Major Special Project of National Science and Technology(No.2014ZX09508003-001-003)the supply of Supernatant FIV of Shandong Taibang Biological Products Limited Company.
文摘Human albumin(HA)is a very important blood product which requires strict quality controlstrategy.Acid precipitation is a key step which has a great effect on the quality of final product.Therefore,a new method based on quality by design(QbD)was proposed to investigate thefeasibility of realizing online quality control with the help of near infrared spectroscopy(NIRS)and chemometrics.The pH value is the critical process parameter(CPP)in acid precipitationprocess,which is used as the end-point indicator.Six batches,a total of 74 samples of acidprecipitation process,were simulated in our lab.Four batches were selected randomly as cali-bration set and remaining two batches as validation set.Then,the analysis based on materialinformation and three dfferent variable selection methods,including interval partial least squaresregression(iPLS),competitive adaptive reweighted sampling(CARS)and correlation coeficient(CC)were compared for eliminating irrelevant variables,Fimally,iPLS was used for variablesselection.The quantitative model was built up by partial least squares regression(PLSR).Thevalues of determination coeficients(R^(2)_(C) and R^(2)_(P)),root mean squares error of prediction(RMSEP),root mean squares error of calibration(RMSEC)and root mean squared error of crossvalidation(RMSECV)were 0.969,0.953,0.0496,0.0695 and 0.0826,respectively.The paired t test and repeatability test showed that the model had good prediction ability and stability.The results indicated that PLSR model could give accurate measurement of the pH value.
基金Supported by the National Natural Science Foundation of PRC.
文摘Some aspects of the fundamental problems of chemometrics are reviewed based on the research work undertaken in this laboratory. The topics touched upon Include analytical information theory, experimental design and optimization, sampling, analytical detection theory, calibration, signal processing, chemical pattern recognition, quantitative structure-activity relationships, digital simulation, and teaching chemometrics as a chemical discipline.
文摘The goal of this study was to use Fourier transform mid-infrared （FTIR） spectroscopy for discrimination of samples of pods and seeds of carob from three Moroccan regions. The origin of samples Pods and seeds of carob could be distinguished from their IR spectra and this measurement was used for discriminate analysis. A multivariate analysis procedure based on the combined use of Hierarchical Cluster Aanalysis （HCA） and Partial Least Squares-Discriminant Analysis （PLS-DA） was tested and provided good classification results. Three distinctive clusters were recognised, related to the three Moroccan regions. Afterwards, PLS-DA was used for the discrimination and classification of the origin of the various Pods and seeds of carob samples. The results demonstrated that the combined use of FTIR and chemometric analysis （cluster analysis and discrimination by PLS- DA） can be used to rapidly and simply determine the origin of carob pulpe samples.
