Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication...Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication. In this paper, we propose an RFID system for detecting counterfeiting products. This RFID system consists of the tag authentication protocol and the database correction protocol. We use the tag authentication protocol for authenticating tags without revealing their sensitive information. This protocol also allows the customer to freely inquire the tag. To prevent the widespread of the counterfeit products, we use the tag status information along with tag identity information. Meanwhile, the database correction protocol guarantees the correctness of the tag status. Our anti-counterfeiting system is the first work considering the seller who plays an important role in the consumer product supply chain. Finally, we show that anti-counterfeiting system is quite secure against counterfeiting and the tag authentication protocol is lightweight enough to be implemented in RFID-based applications.展开更多
Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+she...Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.展开更多
A benzoic acid rare earth(Tb) complex was synthesized and characterized.The excitation and emission spectra of the complex were investigated,and then pure organic complex was incorporated with inorganic matrices(SiO2)...A benzoic acid rare earth(Tb) complex was synthesized and characterized.The excitation and emission spectra of the complex were investigated,and then pure organic complex was incorporated with inorganic matrices(SiO2) through sol-gel method.The composition and structure of the hybrid complex was characterized through the IR spectra,TG,TEM and fluorescent spectrometer.Furthermore,the polypropylene(PP) fluorescent fiber with the organic-inorganic hybrid was prepared by melt spinning.The fluorescent and mechanical properties of the fiber were also tested.The results showed that after sol-gel coating the average particulate dimension of the hybrid rare earth complex was less than 100 nm and thermal stability was improved.Meanwhile,the fiber possessed excellent fluorescent and mechanical properties,which could be used as a candidate applied to excellent fluorescent anti-counterfeiting fiber.展开更多
Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. ...Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. N-Allylquinolinium bromide under 365 nm UV exhibited intense green RTP emission with response upon adding chloroform. This interesting phenomenon endowed N-allylquinolinium bromide great potential as an anti-counterfeiting material.展开更多
Pharmaceutical counterfeiting is a health scourge responsible for several cases of morbidity and mortality. Counterfeit medicines cause therapeutic failure, emergence of resistance in the treatment of infections. This...Pharmaceutical counterfeiting is a health scourge responsible for several cases of morbidity and mortality. Counterfeit medicines cause therapeutic failure, emergence of resistance in the treatment of infections. This study was conducted in order to identify counterfeit and authentic medicines in circulation in Lubumbashi. The study included artemether and artesunate for oral administration. A careful visual inspection of medicine, investigation of authenticity of pharmaceutical products from manufacturers and pharmaceutical regulatory authorities and determination of content were used as study parameters. 52 samples: 37 artemether and 15 of artésunate were collected. 7 samples (13%) have proven to be counterfeit. Artemether was the most counterfeit (71%) and 29% for artesunate. 6 (12%) samples were substandard according to the international pharmacopoeia in terms of content of active ingredient. Sixty-seven percent of non-compliance concerned counterfeit medicines. The proportion of non-compliance is highest among counterfeit medicines (71.43% vs 2.22%;p = 0.000004). It is obvious that strengthening the capacity of the drug regulatory authority of the DRC reduces the influx of counterfeit drug and substandard.展开更多
Counterfeit medicines are a growing problem in both developing and industrialised countries. In general the evaluation of these medicines is limited to the identification and the dosage of the active ingredients. In t...Counterfeit medicines are a growing problem in both developing and industrialised countries. In general the evaluation of these medicines is limited to the identification and the dosage of the active ingredients. In this study in vitro dissolution tests were conducted on two sets of counterfeit medicines containing PDE-5 inhibitors （sildenafil citrate and tadalafil）. The dissolution profiles were statistically compared to the ones of the genuine products using the f2-method and a comparison at each time point using the Cochran test. The results showed low equivalences between counterfeit and genuine products as well as higher variations around the mean dissolution value at the different time points for the counterfeit products.展开更多
In an effort to promote the availability of safe and effective drugs, the US Food and Drug Administration is developing spectroscopic methods to assess the quality of drugs in the field. Here we report a rapid screeni...In an effort to promote the availability of safe and effective drugs, the US Food and Drug Administration is developing spectroscopic methods to assess the quality of drugs in the field. Here we report a rapid screening classification method for Tamiflu (oseltamivir phosphate) capsules using a portable Raman spectrometer to perform screening on three solid oral dosage strengths of Tamiflu, 30 mg, 45 mg and 75 mg. Tamiflu is an antiviral drug that is stockpiled for use in the event of pandemic influenza outbreak. The qualitative classification methods reported were developed using the Raman spectra of intact capsules. The classification algorithms used were able to reliably distinguish the three dosage strengths of Tamiflu. These qualitative models are validated with additional Tamiflu samples from different batches and simulated counterfeits of Tamiflu. The probability that a test sample belongs to each dosage strength class is calculated, and strict class predictions are used to assign each sample to a particular class. The classification methods reported here enable development of user-independent, field-deployable methods for finished drug products and are able to correctly assign 92% of the validation samples using authentic Tamiflu and 100% of the simulated counterfeits.展开更多
February-15,virtual ITU is organizing a series of webinars on Combating counterfeiting and stolen information and communications technology(ICT)devices.The Episode 1:"Existing challenges and solutions on combatin...February-15,virtual ITU is organizing a series of webinars on Combating counterfeiting and stolen information and communications technology(ICT)devices.The Episode 1:"Existing challenges and solutions on combating counterfeiting of ICT devices",will take place fully virtually on 15 February 2023.展开更多
Direct infusion electrospray ionization mass spectrometry (ESI-MS) is shown to provide an efficient tech- nique for the investigation of polar composition of forensic tablets for male erectile dysfunction. ESI-MS fing...Direct infusion electrospray ionization mass spectrometry (ESI-MS) is shown to provide an efficient tech- nique for the investigation of polar composition of forensic tablets for male erectile dysfunction. ESI-MS fingerprinting of 41 commercial sildenafil samples (Viagra?, Cialis?, Lazar?, Libiden?, , Maxfil?, , Plenovit?, Potent 75?, Rigix?, V-50?, Vimax?, Pramil 75? and Pramil?) and 56 counterfeit samples (Viagra and Cialis) were obtained. The spectra for the authentic Viagra? tablets showed abundant ions exclusively corresponding to the sildenafil (SLD) molecule: [SLD + H]+ of m/z 475;[SLD + Na]+ of m/z 497;and [2SLD + H]+ of m/z 949. The spectra for com-mercial sildenafil samples also showed predominat SLD ions. Tablets of authentic Cialis? showed mainly ions of m/z 343, 365 and 707 from the lactose molecule (the excipient);as well as a minor ion of m/z 390 corresponding to the active ingredient tadalafil (TAD) in its protonated form [TAD + H]+. For counterfeit Cialis samples, how-ever, normally TAD ions of much high abundances was observed, together with ions corresponding to sildenafil analogues such as those of m/z 489 (homosildenafil) and 505 (hydroxyhomosildenafil). Principal component analysis was applied to ESI-MS fingerprint data, placing samples according to their contents of active ingredients hence authentic and counterfeit samples are easily recognized.展开更多
Qualification of equipment essential to safety in NPPs （nuclear power plants） ensures its capability to perform designated safety functions on demand under postulated service conditions. However, a number of inciden...Qualification of equipment essential to safety in NPPs （nuclear power plants） ensures its capability to perform designated safety functions on demand under postulated service conditions. However, a number of incidents identified by the NRC （Nuclear Regulatory Commission） since 1980s catalysed the US nuclear industry to adopt standard precautions to guard against counterfeit items. The purpose of this paper is to suggest the NFC （near field communication） based equipment qualification management system preventing counterfeit and fraudulent items. The NEQM （NFC based equipment qualification management） system works with the support of legacy systems such as PMS （procurement management system） and FMS （facility management system）.展开更多
The hydrophilicity, dispersity and minuteness of UV (ultraviolet)-photochromic special function materials and its retention and formation mechanisms in stock were comprehensively studied, and the retention mechanism o...The hydrophilicity, dispersity and minuteness of UV (ultraviolet)-photochromic special function materials and its retention and formation mechanisms in stock were comprehensively studied, and the retention mechanism of UV-photochromic fiber was also studied. In addition, according to the disadvantages of special function materials such as big grain, bad hydrophilicity, expensive price and so on, this paper displays our effects focused on the developing of anti-counterfeit pigments slurry system. Moreover, the properties and anti-counterfeit mechanism of the paper with different special function materials were researched by fluorescent spectrum.展开更多
Highly ordered films of polystyrene(PS)micro-spheres have demonstrated various merits in optoelectronic devices,given their size-and thickness-dependent optical properties.So far,various solution strategies have been ...Highly ordered films of polystyrene(PS)micro-spheres have demonstrated various merits in optoelectronic devices,given their size-and thickness-dependent optical properties.So far,various solution strategies have been developed for making such highly ordered films,which have suffered from the lack of precise control on the film thickness(i.e.,layer number of micro-spheres).Here,we developed a facile fibrous liquid bridge strategy for fabricating highly ordered PS micro-sphere films,featured as the finely tunable mono-to multi-layer.Guided by a horizontally placed fiber with both ends passing through a capillary tube,respectively,the solution was transferred steadily onto the target substrate forming a homogeneous liquid film,whose dewetting process thus confines the assembly ofmicro-spheres in a well-controllablemanner.Depending on both the solution-shearing speed and the local concentration,a dynamic equilibrium between liquid transfer and evaporation was realized,which enables the formation of highly ordered micro-sphere films with finely tunable layer numbers.We demonstrated the angle-specific information encryption for anti-counterfeiting by utilizing patterned PS micro-sphere films that modulate structural colors based on layer-dependent optical responses.The result offers a new perspective for fabricating highly ordered film with tunable layers.展开更多
Developing advanced fluorescence anti-counterfeiting technologies can enhance the effectiveness of current anti-counterfeiting strategies by addressing their limitations.To meet this demand,an afterglow material Y_(2)...Developing advanced fluorescence anti-counterfeiting technologies can enhance the effectiveness of current anti-counterfeiting strategies by addressing their limitations.To meet this demand,an afterglow material Y_(2)CaSnGa_(4)O_(12):Pr^(3+)(YCSG:Pr^(3+))exhibiting photochromic phenomena was engineered.This design capitalizes on the opposite effects of traps and color centers on emission intensity,thus ingeniously achieving excitation wavelength-dependent modifications in luminescence intensity.A thorough analysis of the energy conversion processes before and after irradiation by ultraviolet light was undertaken to discern the dominant role of color centers and traps under varying excitation conditions.Thereby,the dynamic energy conversion processes from traps and color centers to the luminescence center are established,showing a variety of output modes related to wavelength,irradiation time and distance.Furthermore,discrepancies in energy transfer efficiency from traps to different energy levels result in temperature-dependent spectral variations,consequently manifesting distinct colors in afterglow and luminescence at each temperature.This pioneering approach serves as a valuable blueprint for the development of multimode dynamic anti-counterfeiting materials capable of adapting to changes in temperature,irradiation time and irradiation distance by leveraging the synergy between traps and color centers.展开更多
Lanthanide-based luminescent anticounterfeiting materials are widely used in various kinds of products.At present,the conventional lanthanide-based luminescent anticounterfeiting technique is based on photoluminescenc...Lanthanide-based luminescent anticounterfeiting materials are widely used in various kinds of products.At present,the conventional lanthanide-based luminescent anticounterfeiting technique is based on photoluminescence from ultraviolet light irradiation,resulting in the decreased efficiency of anticounterfeiting applications.In this work,we realized three luminescence modes in a perovskite structure(CaTiO_(3):Pr^(3+),Er^(3+)),in which the excitation-wavelength-dependent photoluminescence(PL)emission,afterglow and upconversion luminescence(UCL)of a doped lanthanide were first presented.Upon ultraviolet excitation,the color of the PL emission can be finely tuned from red to orange,yellow and green by increasing the excitation wavelength from 365 nm to 380 nm.The doped lanthanide emits an intense green color upon illumination with a 980 nm excitation source and a long persisting red color(612 nm)when a UV lamp at 365 nm excitation is switched off.Based on the above luminescence modes of CaTiO_(3):Pr^(3+),Er^(3+),a multilevel anticounterfeiting quick response code(QR code)was developed.The QR code readily integrates the advantages of the excitation wavelength-dependent PL emissions,a strong red afterglow and sensitive excitation power-dependent UCL emissions in one overall device.The presented multilevel anticounterfeiting strategies may inspire the resolution of counterfeit issues in various fields.展开更多
Multicolor and multimodal luminescence materials play crucial roles in anti-counterfeiting and encryption technologies due to their attractive properties of colorful,visually identifiable emissions and distinct emissi...Multicolor and multimodal luminescence materials play crucial roles in anti-counterfeiting and encryption technologies due to their attractive properties of colorful,visually identifiable emissions and distinct emission modes in various excitation or stimulus channels.Nevertheless,integrating multicolor and multimodal luminescence via single rare-earth doping based on a single matrix remains a significant challenge.展开更多
To understand the fundamental mechanism of aggregation-induced phosphorescent emission(AIPE)and to improve the development of mechanochromic molecules,five new Pt(II)complexes Pt-1–Pt-5 bearing different terminal sub...To understand the fundamental mechanism of aggregation-induced phosphorescent emission(AIPE)and to improve the development of mechanochromic molecules,five new Pt(II)complexes Pt-1–Pt-5 bearing different terminal substituents on 1,3-di(2-pyridyl)benzene(N^C^N)ligands were designed and synthesized.Their photophysical properties have been investigated systematically via a series of spectroscopic methods.Upon excitation,the solid states of these Pt complexes exhibit tunable emissions from yellow to red,and complexes Pt-2 and Pt-3 with a large steric hindrance display remarkable AIPE properties in a tetrahydrofuran/H_(2)O mixture.All complexes,except Pt-5,show evident mechanochromic and vapochromic behaviors.Based on in-depth experimental studies,the reason for the mechanochromic behavior could be the change in the distance of the neighboring Pt complexes,which causes a switching of the emission state from^(3)π,π*/^(3)MLCT(metal-to-ligand charge transfer)to^(3)MLCT.The above results suggest an example of phosphorescence tuning by a switching of the triplet excited state in the solid state,and provide a mechanism of mechanochromic behavior.Furthermore,complex Pt-2 was used as an emission ink in the field of advanced anti-counterfeiting.展开更多
Here,multimodal fluorescent materials of Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)were synthesized by the traditional high-temperature solid-state reaction method.In this garnet Ca_(3)Al_(2)Ge_(3)O_(12) structure,Mn^(2...Here,multimodal fluorescent materials of Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)were synthesized by the traditional high-temperature solid-state reaction method.In this garnet Ca_(3)Al_(2)Ge_(3)O_(12) structure,Mn^(2+)and Cr^(3+)ions occupy dodecahedral sites(Ca sites)and hexahedral sites(Al sites),and can produce dynamic colortunable persistent luminescence at different concentrations,different excitations,and different temperatures;in particular,continuous luminescence with temperature(300 K–473 K)shows a color change from green to deep red.Through detailed pyrolysis studies and theoretical calculations,it is demonstrated that the double-trap structure existing in the host makes the persistent luminescence color temperaturedependent.Anti-counterfeiting and industrial inspection molds were successfully accomplished,which means Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)may be used in anti-counterfeiting and industrial inspection.展开更多
Luminescent materials play a key role in the field of optical anti-counterfeiting.However,the development of multimode,multi-color dynamic phosphors,making optical anti-counterfeiting more advanced and practical,remai...Luminescent materials play a key role in the field of optical anti-counterfeiting.However,the development of multimode,multi-color dynamic phosphors,making optical anti-counterfeiting more advanced and practical,remains a great challenge.Herein,multimode luminescence(PL,PersL,TL,PSL,and PSPL),dynamic multi-color emission phosphors based on a single CaSb_(2)O_(6)(CSO)host doped with manganese ions were developed and studied in detail for the first time.The partial self-reduction of Mn in the CSO crystal was observed.The self-reduction behavior of Mn could be effectively suppressed by co-doping with La^(3+)ions through unequal substitution of the Ca^(2+)ions.Furthermore,it was found that the multimode and dynamic luminescence properties of the CSO:Mn phosphors could be further modulated by adjusting the La^(3+)doping concentration,which could be used as a new type of anti-counterfeiting materials.Here,a novel four-mode multicolor and dynamic anti-counterfeiting“rose bouquet”pattern was designed,where a portable UV lamp only having two emitting wavelengths(254 and 365 nm)was required to achieve a full anti-counterfeiting effect.This design is low-cost,easy to realize and advanced in terms of functionality,which has great potential for practical applications in the field of optical anticounterfeiting.In addition,its temperature sensor application based on the different thermal-quenching characteristics of Mn2+and Mn4+was also evaluated.展开更多
文摘Counterfeiting is one of the most serious problems in the consumer market. One promising approach for anti-counterfeiting is to attach a low-cost Radio-frequency Identification (RFID) tag to the product authentication. In this paper, we propose an RFID system for detecting counterfeiting products. This RFID system consists of the tag authentication protocol and the database correction protocol. We use the tag authentication protocol for authenticating tags without revealing their sensitive information. This protocol also allows the customer to freely inquire the tag. To prevent the widespread of the counterfeit products, we use the tag status information along with tag identity information. Meanwhile, the database correction protocol guarantees the correctness of the tag status. Our anti-counterfeiting system is the first work considering the seller who plays an important role in the consumer product supply chain. Finally, we show that anti-counterfeiting system is quite secure against counterfeiting and the tag authentication protocol is lightweight enough to be implemented in RFID-based applications.
基金Project(51874129)supported by the National Natural Science Foundation of ChinaProjects(2018JJ3115,2019JJ60049)supported by the Science Foundation of Hunan Province,ChinaProjects(19B153,19B158)supported by the Scientific Research Fund of Hunan Provincial Education Department,China。
文摘Novel hydrophilic NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+double-jacket microtubes(DJMTs)with upconversion/downconversion dual-mode luminescence were designed and prepared through epitaxial growth of NaGdF4:Ce^3+,Eu^3+shell onto the NaYF4:Yb^3+,Tm^3+microtube via poly(acrylic acid)(PAA)mediated hydrothermal method.It is demonstrated that PAA ligand played an important role in guiding the direct growth of NaGdF4:Ce^3+,Eu^3+shell onto the surface of NaYF4:Yb^3+,Tm^3+parent microtubes.The growth of NaGdF4:Ce^3+,Eu^3+shell experienced a crystal phase transition fromβ-NaGdF4 andβ-NaYF4 mixture toβ-NaYF4@NaGdF4 composite crystal,and morphology evolution from mixture ofβ-NaGdF4:Ce^3+,Eu^3+nanorods andβ-NaYF4:Yb^3+,Tm^3+microtubes to NaYF4:Yb^3+,Tm^3+@NaGdF4:Ce^3+,Eu^3+DJMTs.The formation mechanism of DJMTs was the dissolution−renucleation ofβ-NaGdF4:Ce^3+,Eu^3+nanorods and the growth ofβ-NaGdF4:Ce^3+,Eu^3+shell via the classical Ostwald ripening mechanism.The as-prepared DJMTs could exhibit blue upconversion and red downconversion luminescence,which was further made into environmentally benign luminescent inks for creating highly secured and fluorescent-based anti-counterfeiting patterns via inkjet printing.
基金Project supported by the Chinese Ministry of Education (208005)Young Scientist Backbone of Heilongjiang Common Higher University (1154G03)
文摘A benzoic acid rare earth(Tb) complex was synthesized and characterized.The excitation and emission spectra of the complex were investigated,and then pure organic complex was incorporated with inorganic matrices(SiO2) through sol-gel method.The composition and structure of the hybrid complex was characterized through the IR spectra,TG,TEM and fluorescent spectrometer.Furthermore,the polypropylene(PP) fluorescent fiber with the organic-inorganic hybrid was prepared by melt spinning.The fluorescent and mechanical properties of the fiber were also tested.The results showed that after sol-gel coating the average particulate dimension of the hybrid rare earth complex was less than 100 nm and thermal stability was improved.Meanwhile,the fiber possessed excellent fluorescent and mechanical properties,which could be used as a candidate applied to excellent fluorescent anti-counterfeiting fiber.
基金the financial support from the Instrument Developing Project of the Chinese Academy of Sciences (No. YJKYYQ20170009)the National Natural Science Foundation of China(NSFC Nos. 21722603 and 21871083)the Innovation Program of Shanghai Municipal Education Commission
文摘Pure organic room-temperature phosphorescence (RTP) materials have been attracting much attention recently. Herein, we report a facile approach combining heavy atom effect and external solvent stimuli to realize RTP. N-Allylquinolinium bromide under 365 nm UV exhibited intense green RTP emission with response upon adding chloroform. This interesting phenomenon endowed N-allylquinolinium bromide great potential as an anti-counterfeiting material.
文摘Pharmaceutical counterfeiting is a health scourge responsible for several cases of morbidity and mortality. Counterfeit medicines cause therapeutic failure, emergence of resistance in the treatment of infections. This study was conducted in order to identify counterfeit and authentic medicines in circulation in Lubumbashi. The study included artemether and artesunate for oral administration. A careful visual inspection of medicine, investigation of authenticity of pharmaceutical products from manufacturers and pharmaceutical regulatory authorities and determination of content were used as study parameters. 52 samples: 37 artemether and 15 of artésunate were collected. 7 samples (13%) have proven to be counterfeit. Artemether was the most counterfeit (71%) and 29% for artesunate. 6 (12%) samples were substandard according to the international pharmacopoeia in terms of content of active ingredient. Sixty-seven percent of non-compliance concerned counterfeit medicines. The proportion of non-compliance is highest among counterfeit medicines (71.43% vs 2.22%;p = 0.000004). It is obvious that strengthening the capacity of the drug regulatory authority of the DRC reduces the influx of counterfeit drug and substandard.
文摘Counterfeit medicines are a growing problem in both developing and industrialised countries. In general the evaluation of these medicines is limited to the identification and the dosage of the active ingredients. In this study in vitro dissolution tests were conducted on two sets of counterfeit medicines containing PDE-5 inhibitors （sildenafil citrate and tadalafil）. The dissolution profiles were statistically compared to the ones of the genuine products using the f2-method and a comparison at each time point using the Cochran test. The results showed low equivalences between counterfeit and genuine products as well as higher variations around the mean dissolution value at the different time points for the counterfeit products.
文摘In an effort to promote the availability of safe and effective drugs, the US Food and Drug Administration is developing spectroscopic methods to assess the quality of drugs in the field. Here we report a rapid screening classification method for Tamiflu (oseltamivir phosphate) capsules using a portable Raman spectrometer to perform screening on three solid oral dosage strengths of Tamiflu, 30 mg, 45 mg and 75 mg. Tamiflu is an antiviral drug that is stockpiled for use in the event of pandemic influenza outbreak. The qualitative classification methods reported were developed using the Raman spectra of intact capsules. The classification algorithms used were able to reliably distinguish the three dosage strengths of Tamiflu. These qualitative models are validated with additional Tamiflu samples from different batches and simulated counterfeits of Tamiflu. The probability that a test sample belongs to each dosage strength class is calculated, and strict class predictions are used to assign each sample to a particular class. The classification methods reported here enable development of user-independent, field-deployable methods for finished drug products and are able to correctly assign 92% of the validation samples using authentic Tamiflu and 100% of the simulated counterfeits.
文摘February-15,virtual ITU is organizing a series of webinars on Combating counterfeiting and stolen information and communications technology(ICT)devices.The Episode 1:"Existing challenges and solutions on combating counterfeiting of ICT devices",will take place fully virtually on 15 February 2023.
文摘Direct infusion electrospray ionization mass spectrometry (ESI-MS) is shown to provide an efficient tech- nique for the investigation of polar composition of forensic tablets for male erectile dysfunction. ESI-MS fingerprinting of 41 commercial sildenafil samples (Viagra?, Cialis?, Lazar?, Libiden?, , Maxfil?, , Plenovit?, Potent 75?, Rigix?, V-50?, Vimax?, Pramil 75? and Pramil?) and 56 counterfeit samples (Viagra and Cialis) were obtained. The spectra for the authentic Viagra? tablets showed abundant ions exclusively corresponding to the sildenafil (SLD) molecule: [SLD + H]+ of m/z 475;[SLD + Na]+ of m/z 497;and [2SLD + H]+ of m/z 949. The spectra for com-mercial sildenafil samples also showed predominat SLD ions. Tablets of authentic Cialis? showed mainly ions of m/z 343, 365 and 707 from the lactose molecule (the excipient);as well as a minor ion of m/z 390 corresponding to the active ingredient tadalafil (TAD) in its protonated form [TAD + H]+. For counterfeit Cialis samples, how-ever, normally TAD ions of much high abundances was observed, together with ions corresponding to sildenafil analogues such as those of m/z 489 (homosildenafil) and 505 (hydroxyhomosildenafil). Principal component analysis was applied to ESI-MS fingerprint data, placing samples according to their contents of active ingredients hence authentic and counterfeit samples are easily recognized.
文摘Qualification of equipment essential to safety in NPPs （nuclear power plants） ensures its capability to perform designated safety functions on demand under postulated service conditions. However, a number of incidents identified by the NRC （Nuclear Regulatory Commission） since 1980s catalysed the US nuclear industry to adopt standard precautions to guard against counterfeit items. The purpose of this paper is to suggest the NFC （near field communication） based equipment qualification management system preventing counterfeit and fraudulent items. The NEQM （NFC based equipment qualification management） system works with the support of legacy systems such as PMS （procurement management system） and FMS （facility management system）.
文摘The hydrophilicity, dispersity and minuteness of UV (ultraviolet)-photochromic special function materials and its retention and formation mechanisms in stock were comprehensively studied, and the retention mechanism of UV-photochromic fiber was also studied. In addition, according to the disadvantages of special function materials such as big grain, bad hydrophilicity, expensive price and so on, this paper displays our effects focused on the developing of anti-counterfeit pigments slurry system. Moreover, the properties and anti-counterfeit mechanism of the paper with different special function materials were researched by fluorescent spectrum.
基金supported by the National Key R&D Program of China(2023YFA1406200)the National Natural Science Foundation of China(T2521005,12174144,12474009,12174146,and 124B2059)the Special Construction Project Fund for Shan-dong Province Taishan Scholars.
文摘Multifunctional optical responsive materials have grown increasingly pivotal in addressingthe escalating demands of sensing,detection,and anti-counterfeiting applications[1,2].These materials exhibit distinct visible optical variations upon exposure to external stimuli,such as pressure,temperature,light,solvents,pH fluctuations,or mechanical force.Fluorescent sensing and anti-counterfeiting technologies leveraging these optical responses have emerged as highly promising solutions.
基金supported by the National Natural Science Foundation of China(nos.22125201,22532003,and 22405014)the China Post-Doctoral Science Foundation(no.2023 M740182)Suzhou Key Laboratory of Bio-Inspired Interfacial Science(SZ2024004).
文摘Highly ordered films of polystyrene(PS)micro-spheres have demonstrated various merits in optoelectronic devices,given their size-and thickness-dependent optical properties.So far,various solution strategies have been developed for making such highly ordered films,which have suffered from the lack of precise control on the film thickness(i.e.,layer number of micro-spheres).Here,we developed a facile fibrous liquid bridge strategy for fabricating highly ordered PS micro-sphere films,featured as the finely tunable mono-to multi-layer.Guided by a horizontally placed fiber with both ends passing through a capillary tube,respectively,the solution was transferred steadily onto the target substrate forming a homogeneous liquid film,whose dewetting process thus confines the assembly ofmicro-spheres in a well-controllablemanner.Depending on both the solution-shearing speed and the local concentration,a dynamic equilibrium between liquid transfer and evaporation was realized,which enables the formation of highly ordered micro-sphere films with finely tunable layer numbers.We demonstrated the angle-specific information encryption for anti-counterfeiting by utilizing patterned PS micro-sphere films that modulate structural colors based on layer-dependent optical responses.The result offers a new perspective for fabricating highly ordered film with tunable layers.
基金supported by the National Natural Science Foundation of China(Grant No.52072364 and 22175169)Program of Science and Technology Development Plan,Jilin Province,China(YDZJ202302CXJD065).
文摘Developing advanced fluorescence anti-counterfeiting technologies can enhance the effectiveness of current anti-counterfeiting strategies by addressing their limitations.To meet this demand,an afterglow material Y_(2)CaSnGa_(4)O_(12):Pr^(3+)(YCSG:Pr^(3+))exhibiting photochromic phenomena was engineered.This design capitalizes on the opposite effects of traps and color centers on emission intensity,thus ingeniously achieving excitation wavelength-dependent modifications in luminescence intensity.A thorough analysis of the energy conversion processes before and after irradiation by ultraviolet light was undertaken to discern the dominant role of color centers and traps under varying excitation conditions.Thereby,the dynamic energy conversion processes from traps and color centers to the luminescence center are established,showing a variety of output modes related to wavelength,irradiation time and distance.Furthermore,discrepancies in energy transfer efficiency from traps to different energy levels result in temperature-dependent spectral variations,consequently manifesting distinct colors in afterglow and luminescence at each temperature.This pioneering approach serves as a valuable blueprint for the development of multimode dynamic anti-counterfeiting materials capable of adapting to changes in temperature,irradiation time and irradiation distance by leveraging the synergy between traps and color centers.
基金financial support from the National Natural Science Foundation of China(Grant No.21871122 and 21431002)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2020-kb13).
文摘Lanthanide-based luminescent anticounterfeiting materials are widely used in various kinds of products.At present,the conventional lanthanide-based luminescent anticounterfeiting technique is based on photoluminescence from ultraviolet light irradiation,resulting in the decreased efficiency of anticounterfeiting applications.In this work,we realized three luminescence modes in a perovskite structure(CaTiO_(3):Pr^(3+),Er^(3+)),in which the excitation-wavelength-dependent photoluminescence(PL)emission,afterglow and upconversion luminescence(UCL)of a doped lanthanide were first presented.Upon ultraviolet excitation,the color of the PL emission can be finely tuned from red to orange,yellow and green by increasing the excitation wavelength from 365 nm to 380 nm.The doped lanthanide emits an intense green color upon illumination with a 980 nm excitation source and a long persisting red color(612 nm)when a UV lamp at 365 nm excitation is switched off.Based on the above luminescence modes of CaTiO_(3):Pr^(3+),Er^(3+),a multilevel anticounterfeiting quick response code(QR code)was developed.The QR code readily integrates the advantages of the excitation wavelength-dependent PL emissions,a strong red afterglow and sensitive excitation power-dependent UCL emissions in one overall device.The presented multilevel anticounterfeiting strategies may inspire the resolution of counterfeit issues in various fields.
基金supported by the National Natural Science Foundation of China(Grant No.21871122 and 21431002)the Fundamental Research Funds for the Central Universities(Grant No.lzujbky-2021-kb17).
文摘Multicolor and multimodal luminescence materials play crucial roles in anti-counterfeiting and encryption technologies due to their attractive properties of colorful,visually identifiable emissions and distinct emission modes in various excitation or stimulus channels.Nevertheless,integrating multicolor and multimodal luminescence via single rare-earth doping based on a single matrix remains a significant challenge.
基金support pro-vided in part by the Natural Science Foundation of Jiangsu Province-Outstanding Youth Foundation(BK20170104)the National Natural Science Foundation of China(21602106)+2 种基金the Six Talent Peaks Project in Jiangsu Province(XCL-037)the Strategic Pioneer Program on Space Science,Chinese Academy of Sciences(XDA15013100 and XDA15013101)the Undergraduate Innovation and Entrepreneurship Training Program(201910291053Z).
文摘To understand the fundamental mechanism of aggregation-induced phosphorescent emission(AIPE)and to improve the development of mechanochromic molecules,five new Pt(II)complexes Pt-1–Pt-5 bearing different terminal substituents on 1,3-di(2-pyridyl)benzene(N^C^N)ligands were designed and synthesized.Their photophysical properties have been investigated systematically via a series of spectroscopic methods.Upon excitation,the solid states of these Pt complexes exhibit tunable emissions from yellow to red,and complexes Pt-2 and Pt-3 with a large steric hindrance display remarkable AIPE properties in a tetrahydrofuran/H_(2)O mixture.All complexes,except Pt-5,show evident mechanochromic and vapochromic behaviors.Based on in-depth experimental studies,the reason for the mechanochromic behavior could be the change in the distance of the neighboring Pt complexes,which causes a switching of the emission state from^(3)π,π*/^(3)MLCT(metal-to-ligand charge transfer)to^(3)MLCT.The above results suggest an example of phosphorescence tuning by a switching of the triplet excited state in the solid state,and provide a mechanism of mechanochromic behavior.Furthermore,complex Pt-2 was used as an emission ink in the field of advanced anti-counterfeiting.
基金supported by the National Natural Science Foundation of China(No.51902080)the central government to guide local scientific and Technological Development(No.206Z1102G and 216Z1101G)Post-graduate’s Innovation Fund Project of Hebei University(HBU2022bs014).
文摘Here,multimodal fluorescent materials of Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)were synthesized by the traditional high-temperature solid-state reaction method.In this garnet Ca_(3)Al_(2)Ge_(3)O_(12) structure,Mn^(2+)and Cr^(3+)ions occupy dodecahedral sites(Ca sites)and hexahedral sites(Al sites),and can produce dynamic colortunable persistent luminescence at different concentrations,different excitations,and different temperatures;in particular,continuous luminescence with temperature(300 K–473 K)shows a color change from green to deep red.Through detailed pyrolysis studies and theoretical calculations,it is demonstrated that the double-trap structure existing in the host makes the persistent luminescence color temperaturedependent.Anti-counterfeiting and industrial inspection molds were successfully accomplished,which means Ca_(3)Al_(2)Ge_(3)O_(12):Mn^(2+),Cr^(3+)may be used in anti-counterfeiting and industrial inspection.
文摘Luminescent materials play a key role in the field of optical anti-counterfeiting.However,the development of multimode,multi-color dynamic phosphors,making optical anti-counterfeiting more advanced and practical,remains a great challenge.Herein,multimode luminescence(PL,PersL,TL,PSL,and PSPL),dynamic multi-color emission phosphors based on a single CaSb_(2)O_(6)(CSO)host doped with manganese ions were developed and studied in detail for the first time.The partial self-reduction of Mn in the CSO crystal was observed.The self-reduction behavior of Mn could be effectively suppressed by co-doping with La^(3+)ions through unequal substitution of the Ca^(2+)ions.Furthermore,it was found that the multimode and dynamic luminescence properties of the CSO:Mn phosphors could be further modulated by adjusting the La^(3+)doping concentration,which could be used as a new type of anti-counterfeiting materials.Here,a novel four-mode multicolor and dynamic anti-counterfeiting“rose bouquet”pattern was designed,where a portable UV lamp only having two emitting wavelengths(254 and 365 nm)was required to achieve a full anti-counterfeiting effect.This design is low-cost,easy to realize and advanced in terms of functionality,which has great potential for practical applications in the field of optical anticounterfeiting.In addition,its temperature sensor application based on the different thermal-quenching characteristics of Mn2+and Mn4+was also evaluated.
