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1.
Adv Exp Med Biol ; 1430: 211-219, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37526850

RESUMO

Due to rapid development of biotechnology in recent years, the field of regenerative medicine has attracted considerable attention. Regenerative medicine-related regulations have been established in several countries to ensure the quality, safety, and efficacy of innovative treatments. Considering the diversity of regenerative medicine, the regulatory framework in Taiwan has been adjusted in response to global trend and local demand. Before 2010, cell and gene therapies were regarded as "new medical practice" under the "Medical Care Act." Along with the establishment of Taiwan Food and Drug Administration (TFDA) in 2010, regenerative medicine was regulated as "medicinal products" under the "Pharmaceutical Affairs Act." Then, the Ministry of Health and Welfare (MOHW) established a new dual-track regulatory pathway for regenerative medicine in 2016. The dual-track pathway divided regenerative medicine into medical practices and medicinal products, aiming to improve the accessibility of new treatments to patients and maintain the flexibility for clinical operations. In order to refine the regulation, the MOHW proposed two draft Acts for regenerative medicine in 2022. The two draft Acts are currently under legislative process. It is expected that the research and development of regenerative medicine can be further accelerated, thus providing early access to innovative therapies for patients in the future.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Medicina Regenerativa , Humanos , Taiwan , Terapia Genética , Biotecnologia
2.
Steroids ; 165: 108739, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33075400

RESUMO

Corticosteroids were used normally as anti-inflammatory drugs. However, in some area certain corticosteroids might be illegally used as growth promoting agent in feed, and as prohibited doping substances in game and sport for human or/and animal performance-enhancing. Synthesized structural similar corticosteroids were popular in black market because they can pass routine drug screening. In this study two new artificial synthesized corticosteroids were found in claimed hydrolyzed wheat product. Liquid chromatography coupled with high resolution mass spectrometry (HRMS, Orbitrap) was applied to separate and elucidate the corticosteroids in the sample. Two unknown peaks with optical spectra similar to corticosteroids were first screened out at the beginning, and then their accurate molecular weight (M + H+) m/z 533.29059 and m/z 603.33289 were detected by HRMS. Element formulas of unknowns were calculated by the accurate mass and isotopes abundance. Structures were proposed by their fragment ions at high energy collision dissociation (HCD, 10 eV) and compared with candidate standard compounds. The two unknowns shared similar molecular skeleton with steroid core structure and presented man made fluorine element in their molecule. As the results, the unknowns in the sample were artificial synthesized, and the sample product was not a real food. The detected corticosteroids were also synthesized as reference compounds for conformation. Two new corticosteroids named betamethasone dibutyrate and betamethasone tributyrate were found and first time reported in this work. The legality of structural similar/modified corticosteroids were blurry and their safety were unverified. The confirmed identifications of two new found corticosteroids, and their mass spectra were provided in this paper for the reference of drug detection.


Assuntos
Betametasona , Cromatografia Líquida , Dopagem Esportivo , Humanos
3.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1130-1131: 121788, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31670109

RESUMO

Multilayer print designs are commonly used in commercial food packaging to attract consumers. UV-curable ink is generally used in this type of printing due to its ease of application, space saving, and rapid drying; however, there have been a number of health alerts related to the contamination of food by photoinitiators in UV-curable ink. In this study, we established a multi-analyte method by which to detect 30 photoinitiators simultaneously. We then applied this method to the analysis of five breakfast cereals and ten types of packaged juice to detect the presence of photoinitiator contamination. Sample treatment was performed using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method for the extraction of photoinitiators. Chromatographic separation of two isomers, methylbenzophenone (MBP) and isopropylthioxanthone (ITX), was achieved using a pentafluorophenyl propyl (PFP) column (1.7 µm, 100 × 2.1 mm i.d.) and MeOH: 5 mM formic acid-ammonium formate (pH 4.0) in gradient elution. The average recovery of photoinitiators from cereal was between 62.0 and 120.3%, with a coefficient of variation between 0.4 and 14.4%. The average recovery of photoinitiators from packaged juices was between 84.4 and 122.9% with a coefficient of variation between 0.5 and 9.5%. The contamination results were as follows: 13.1 ng/g triphenyl phosphate (TPP) was detected in one breakfast cereal, and 2-hydroxy-4-methoxy benzophenone (BP-3), 1-hydroxycyclohexyl phenyl-ketone (Irgacure 184), methyl-2-benzoylbenzoate (MOBB), and 2,4-diethyl-9H-thioxanthen-9-one (DETX) were detected in one of the packaged juices at levels ranging from 2.2 to 152.9 ng/g.


Assuntos
Grão Comestível/química , Contaminação de Alimentos/análise , Embalagem de Alimentos , Sucos de Frutas e Vegetais/análise , Tinta , Benzofenonas/análise , Desjejum , Cromatografia Líquida de Alta Pressão , Grão Comestível/normas , Sucos de Frutas e Vegetais/normas , Modelos Lineares , Fotoquímica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem , Tioxantenos/análise , Xantonas/análise
4.
J Food Drug Anal ; 27(3): 749-757, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31324290

RESUMO

A simple gradient high-performance liquid chromatography with diode array detection (HPLC-DAD) method was used to simultaneously to analyze characteristics of six indicator compounds in the traditional Chinese medicine (TCM) formulation Wen-Qing-Yin (WQY). Separate optimization was performed using a Cosmosil C18 column gradient method with 0.1% formic acid in both mobile phases of aqueous and acetonitrile (ACN), at a flow rate, detection wavelength, and sample volume of 1.8 mL/min, 268 nm, and 10 µL, respectively. The linear regression of six active compounds berberine (BER), baicalin (BAI), ferulic acid (FER), geniposide (GEN), hydorxymethoxylfurfural (HMF), and paeoniflorin (PAE) was produced at the concentration range of 10-2000 µg/mL. The method validation revealed an acceptable precision (intra- and inter-day precision < 3.39% and 4.11%, respectively) and recovery (85.60-110.45% and 86.58-110.90%), a recovery range of 86.61-109.42%, and sensitivity (limit of detection [LOD] and limit of quantification [LOQ] values were in the range of 0.03-3.13, and 0.08-9.38 µg/mL, respectively) while the calibration curves were linear with a correlation coefficient (R2) ranging from 0.9966 to 0.9989. The qualitative and quantitative analyses were performed by direct comparison of the peaks of the WCY extract to retention times of reference standards. Additionally, principal component analysis (PCA) successfully discriminated four purchased commercial samples of all six indicator constituents, and the present results indicate their comprehensive potential usefulness for qualitative and quantitative analyses of the WQY decoction and its commercial products.


Assuntos
Berberina/análise , Ácidos Cumáricos/análise , Medicamentos de Ervas Chinesas/química , Flavonoides/análise , Furaldeído/análise , Glucosídeos/análise , Iridoides/análise , Monoterpenos/análise , Cromatografia Líquida de Alta Pressão , Medicina Tradicional Chinesa
5.
J Food Drug Anal ; 27(3): 815-824, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31324297

RESUMO

A gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) method is developed to determine 18 representative polycyclic aromatic hydrocarbons (PAHs) in cosmetics, including Benzo[a]pyrene (BaP) and others. The method offers high sensitivity and selectivity under selected reaction monitoring (SRM) mode to satisfy the requirements of both quantitation and qualitation. The extraction solvent system used in this study is acetone/hexane 1:1 (v/v) and other purification procedure is unnecessary. The linearities of 18 PAHs are validated in different concentration in the range of 0.25-20 ng/mL individually with coefficient correlation (r) higher than 0.996. The recoveries for spiking 3 different concentrations are from 87.40% to 120.44% for 18 PAHs and the coefficient of variation (CV) are below 12.32%. Limit of quantification (LOQ) of 18 PAHs is in the range of 0.05-0.2 mg/kg. A matrix enhancement effect is observed and can be compensated with deuterated internal standard. The method has been successfully applied to 73 samples, over 40 of them are lipsticks. The results show none of the samples detect Benzo[a]pyrene (BaP) and Dibenzo[a,h]anthracene (DBA), both are classified as the most carcinogenic. 8 PAHs are detected and the average value between 0.08 and 0.27 mg/kg. This study offers a sensitive and simple method to analyze 18 representative PAHs successfully and can be applied to cosmetic products and raw materials.


Assuntos
Cosméticos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Cromatografia Gasosa , Espectrometria de Massas em Tandem
6.
Biomed Res Int ; 2018: 9398647, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29888286

RESUMO

This study performs a structural optimization of anatomical thin titanium mesh (ATTM) plate and optimal designed ATTM plate fabricated using additive manufacturing (AM) to verify its stabilization under fatigue testing. Finite element (FE) analysis was used to simulate the structural bending resistance of a regular ATTM plate. The Taguchi method was employed to identify the significance of each design factor in controlling the deflection and determine an optimal combination of designed factors. The optimal designed ATTM plate with patient-matched facial contour was fabricated using AM and applied to a ZMC comminuted fracture to evaluate the resting maxillary micromotion/strain under fatigue testing. The Taguchi analysis found that the ATTM plate required a designed internal hole distance to be 0.9 mm, internal hole diameter to be 1 mm, plate thickness to be 0.8 mm, and plate height to be 10 mm. The designed plate thickness factor primarily dominated the bending resistance up to 78% importance. The averaged micromotion (displacement) and strain of the maxillary bone showed that ZMC fracture fixation using the miniplate was significantly higher than those using the AM optimal designed ATTM plate. This study concluded that the optimal designed ATTM plate with enough strength to resist the bending effect can be obtained by combining FE and Taguchi analyses. The optimal designed ATTM plate with patient-matched facial contour fabricated using AM provides superior stabilization for ZMC comminuted fractured bone segments.


Assuntos
Fraturas Maxilares/cirurgia , Fraturas Cranianas/cirurgia , Telas Cirúrgicas , Fraturas Zigomáticas/cirurgia , Fenômenos Biomecânicos , Placas Ósseas , Parafusos Ósseos , Análise de Elementos Finitos , Fixação Interna de Fraturas/métodos , Humanos , Fraturas Maxilares/fisiopatologia , Fraturas Cranianas/fisiopatologia , Estresse Mecânico , Titânio/uso terapêutico , Fraturas Zigomáticas/fisiopatologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-29601254

RESUMO

A novel compound structurally similar to tadalafil was found in a dietary supplement by adulterants screening test and isolated by column chromatography. After analysis by accurate mass, nuclear magnetic resonance (NMR) and X-ray, the structure of this novel tadalafil analogue was determined as (5R, 16R)-5-(1,3-benzodioxol-5-yl)-2- (3-ethypentan-3-yl)-15,16-dihydro(1H-imidazo[1,5-a]pyrido)[3,4-b]indol-1,3-dion.


Assuntos
Suplementos Nutricionais/análise , Tadalafila/análise , Cromatografia Líquida , Cromatografia em Camada Fina , Cristalografia por Raios X , Cromatografia Gasosa-Espectrometria de Massas , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estrutura Molecular , Tadalafila/análogos & derivados , Espectrometria de Massas em Tandem
8.
J Food Drug Anal ; 26(2): 628-636, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29567232

RESUMO

This study discusses the strategies on sample preparation to acquire images with sufficient quality for size characterization by scanning electron microscope (SEM) using two commercial ZnO nanoparticles of different surface properties as a demonstration. The central idea is that micrometer sized aggregates of ZnO in powdered forms need to firstly be broken down to nanosized particles through an appropriate process to generate nanoparticle dispersion before being deposited on a flat surface for SEM observation. Analytical tools such as contact angle, dynamic light scattering and zeta potential have been utilized to optimize the procedure for sample preparation and to check the quality of the results. Meanwhile, measurements of zeta potential values on flat surfaces also provide critical information and save lots of time and efforts in selection of suitable substrate for particles of different properties to be attracted and kept on the surface without further aggregation. This simple, low-cost methodology can be generally applied on size characterization of commercial ZnO nanoparticles with limited information from vendors.


Assuntos
Microscopia Eletrônica de Varredura/métodos , Nanopartículas/química , Óxido de Zinco/química , Microscopia Eletrônica de Varredura/economia , Tamanho da Partícula , Propriedades de Superfície
9.
J AOAC Int ; 101(3): 677-685, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28964271

RESUMO

An interlaboratory study was conducted to evaluate stable isotope dilution and LC tandem MS (MS/MS) for the determination of aflatoxins B1, B2, G1, G2, and M1 (AFB1, AFB2, AFG1, AFG2, and AFM1) in milk, milk-based infant formula (formula), and feed. Samples were first fortified with five 13C uniformly labeled aflatoxins {[13C]-internal standard (IS)} corresponding to the five native aflatoxins, which were subsequently extracted with acetonitrile-water (50 + 50, v/v), followed by centrifugation, filtration, and LC-MS/MS analysis. In addition to certified milk powder and animal feed, the three participating laboratories also analyzed milk, formula, and feed fortified with the five aflatoxins at concentrations ranging from 0.5 to 50 ng/g. The majority of recoveries ranged from 80 to 120%, with RSDs < 20%. Method LOQs were determined by the three laboratories using the three sample matrixes in replicates (n = 8), and the determined LOQs of AFB1, AFB2, AFG1, AFG2, and AFM1 ranged from 0.1 to 0.91, 0.24 to 0.64, 0.28 to 1.52, 0.19 to 3.80, and 0.12 to 0.45 ng/g, respectively. For detected aflatoxins in the certified materials, all measured concentrations were within ±25% of the certified values. Using [13C]-IS eliminated the need for matrix-matched calibration standards for quantitation, simplified sample preparation, and achieved simultaneous identification and quantitation of the aflatoxins in a simple LC-MS/MS procedure.


Assuntos
Aflatoxinas/análise , Ração Animal/análise , Fórmulas Infantis/análise , Leite/química , Aflatoxinas/química , Animais , Isótopos de Carbono , Cromatografia Líquida/métodos , Humanos , Lactente , Leite/microbiologia , Espectrometria de Massas em Tandem/métodos
10.
Biosens Bioelectron ; 96: 167-172, 2017 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-28494368

RESUMO

The binding of organometallic osmium carbonyl clusters onto the surface of gold nanoparticles (10OsCO-Au NPs) greatly enhanced the CO stretching vibration signal at ~2100cm-1, which is relatively free from interference due to the absorbance of biomolecules. By utilizing the acetylcholinesterase (AChE) mediated hydrolysis of acetylthiocholine to thiocholine where the activity of AChE is inhibited by the presence of organophosphate pesticides (OPPs), the subsequent thiocholine-induced aggregation of 10OsCO-Au NPs can be monitored by the change in color of the NPs solution and the variation in intensity of the SERS CO signal. The change in color offers a fast pre-screening method, whereas monitoring via SERS is used for greater accuracy and lower limit of detection (0.1 ppb) for quantitative detection. Its potential as a quick and accurate method of OPPs monitoring in consumer products was demonstrated in the detection of OPPs in real spiked samples such as beer.


Assuntos
Análise de Alimentos/métodos , Ouro/química , Nanopartículas Metálicas/química , Compostos Organofosforados/análise , Praguicidas/análise , Ressonância de Plasmônio de Superfície/métodos , Acetilcolinesterase/química , Acetiltiocolina/química , Cerveja/análise , Glicina/análogos & derivados , Glicina/análise , Hidrólise , Nanopartículas Metálicas/ultraestrutura , Tiocolina/química , Glifosato
11.
Food Addit Contam Part B Surveill ; 10(3): 233-239, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28494640

RESUMO

The adulteration of olive oil is an important issue around the world. This paper reports an indirect method by which to identify 3-monochloropropane-1,2-diol (3-MCPD) esters in olive oils. Following sample preparation, the samples were spiked with 1,2-bis-palmitoyl-3-chloropropanediol standard for analysis using gas chromatograph-tandem mass spectrometry. The total recovery ranged from 102.8% to 105.5%, the coefficient of variation ranged from 1.1% to 10.1%, and the limit of quantification was 0.125 mg/kg. The content of 3-MCPD esters in samples of refined olive oil (0.97-20.53 mg/kg) exceeded those of extra virgin olive oil (non-detected to 0.24 mg/kg). These results indicate that the oil refining process increased the content of 3-MCPD esters, which means that they could be used as a target compound for the differentiation of extra virgin olive oil from refined olive oil in order to prevent adulteration.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Azeite de Oliva/química , alfa-Cloridrina/química , Cloretos , Reprodutibilidade dos Testes
12.
Cell Transplant ; 26(3): 483-492, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-27697103

RESUMO

Cell therapy is not only a novel medical practice but also a medicinal product [cell therapy product (CTP)]. More and more CTPs are being approved for marketing globally because of the rapid development of biomedicine in cell culture, preservation, and preparation. However, regulation is the most important criterion for the development of CTPs. Regulations must be flexible to expedite the process of marketing for new CTPs. Recently, the Taiwan Food and Drug Administration (TFDA) updated the related regulations such as regulation of development, current regulatory framework and process, and the application and evaluation processes. When the quality of CTPs has been improved significantly, their safety and efficacy are further ensured. The treatment protocol, a new design for adaptive licensing to current clinical practice, is a rapid process for patients with life-threatening diseases or serious conditions for which there are no suitable drugs, medical devices, or other therapeutic methods available. The hospital can submit the treatment protocol to apply for cell therapy as a medical practice, which may result in easier and faster cell therapy development, and personalized treatment for individual patients will evolve quickly.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/normas , Terapia Baseada em Transplante de Células e Tecidos/efeitos adversos , Terapia Baseada em Transplante de Células e Tecidos/estatística & dados numéricos , Hospitais/estatística & dados numéricos , Taiwan
13.
Artigo em Inglês | MEDLINE | ID: mdl-28008796

RESUMO

A novel sildenafil analogue found in herbal products by a routine drug-adulteration screening programme was isolated by column chromatography. On the basis of extensive 1D- and 2D-nuclear magnetic resonance (NMR) spectroscopy and mass spectral analysis, the structure of a new compound YJ-07 was established as 1-[4-ethoxy-3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-5-yl) benzenesulfonamide. It common name is aminosildenafil.


Assuntos
Contaminação de Medicamentos , Medicamentos de Ervas Chinesas/química , Citrato de Sildenafila/análogos & derivados , Citrato de Sildenafila/análise , Estrutura Molecular
14.
Artigo em Inglês | MEDLINE | ID: mdl-27645562

RESUMO

In a maca-containing herbal supplement claimed to remedy erectile dysfunction, a new sildenafil analogue was found using adulterant screening with TLC, GC-MS and LC-MS/MS. This compound was isolated by column chromatography and HPLC, and identified by extensive 1D- and 2D-NMR and mass spectral analyses. The structure of this new compound was established as 5-[2-ethoxy-5-(piperazine-1-carbonyl) phenyl]-1-methyl-3-propyl-1,6-dihydro-pyrazolo[4,3-d]pyrimidin-7-one, and was named desethylcarbodenafil.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Citrato de Sildenafila/análogos & derivados , Estrutura Molecular , Citrato de Sildenafila/análise , Citrato de Sildenafila/química
15.
Artigo em Inglês | MEDLINE | ID: mdl-27143524

RESUMO

A novel tadalafil analogue in a dietary supplement was found by drug-adulteration screening and isolated by column chromatography and HPLC. Based on extensive 1D- and 2D-NMR and mass spectral analyses, the structure of this new compound was determined as 2-(N,N-dipropyl acetyl) 3-methyl 1-(benzo[d][1,3]dioxol-5-yl)-3,4-dihydro-1H-pyrido[3,4-b]indole-3-carboxylate - its common name is dipropylaminopretadalafil.


Assuntos
Tadalafila/análogos & derivados , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais/análise , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Tadalafila/análise , Tadalafila/química
16.
Biomed Chromatogr ; 30(9): 1449-57, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26873449

RESUMO

Cinnamon bark (Rou Gui in Chinese), cinnamon twig (Gui Zhi) and shaved cinnamon bark (Gui Sin) have been widely used as spices and in traditional Chinese medicine since ancient times. On-going issues related to quality and authenticity necessitate the development of analytical methods capable of providing an objective evaluation of samples. In this study, chemical fingerprints of cinnamon bark, cinnamon twigs and shaved cinnamon bark were established using liquid chromatography quadruple time-of-flight mass spectrometry in conjunction with principal component analysis (PCA). From 125 samples of cinnamon, we identified the following eight compounds and their the detection ratios: coumarin, cinnamaldehyde, cinnamyl alcohol, cinnamic acid, 2-hydroxycinnamaldehyde, 2-hydroxycinnamic acid, 2-methoxycinnamaldehyde and 4-methoxycinnamaldehyde. Of these, 4-methoxycinnamaldehyde presented the largest variations in detection ratio, making up 64.0, 97.4 and 50.0% in cinnamon bark, cinnamon twig, and shaved cinnamon bark, respectively. The quantities of cinnamyl alcohol, coumarin and cinnamaldehyde also varied between the three parts of the plant. Chemical fingerprints of the three cinnamon samples were established using principal component analysis, the results of which indicate that cinnamon bark and shaved cinnamon bark could be easily differentiated, despite a marked similarity in outward appearance. Cinnamon twig was also shown to depart from the other clusters. The proposed method provides a fast and efficient means of identifying cinnamon herbs for quality control purposes. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Cromatografia Líquida/métodos , Cinnamomum aromaticum , Espectrometria de Massas/métodos , Estruturas Vegetais , Padrões de Referência
17.
Artigo em Inglês | MEDLINE | ID: mdl-26635133

RESUMO

A novel tadalafil analogue found in a dietary supplement by routine drug-adulteration screening was isolated by column chromatography and HPLC. On the basis of extensive 1D- and 2D-nuclear magnetic resonance (NMR), infrared (IR) and mass spectral analyses, the structure of the new compound YJ-02 was established as 6-(benzo[d][1,3]dioxol-5-yl)-2,3,6,7,12,12a-hexahydro-2-(1E,2E)-3-phenylallylidene)amino)pyrazino[1',2':1,6]pyrido[3,4-b]indole-1,4-dione. Its common name is N-phenylpropenyltadalafil.


Assuntos
Suplementos Nutricionais , Contaminação de Alimentos/análise , Tadalafila/análise , Tadalafila/química , Estrutura Molecular , Tadalafila/isolamento & purificação
18.
J Anal Toxicol ; 40(1): 12-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26410364

RESUMO

In recent years, the abuse of synthetic cathinones has increased considerably. This study proposes a method, based on gas chromatography/mass spectrometry (GC-MS), to analyze and quantify six synthetic cathinones in urine samples: mephedrone (4-MMC), methylone (bk-MDMA), butylone, ethylone, pentylone and methylenedioxypyrovalerone (MDPV). In our procedure, the urine samples undergo solid-phase extraction (SPE) and derivatization prior to injection into the GC-MS device. Separation is performed using a HP-5MS capillary column. The use of selective ion monitoring (SIM mode) makes it is good sensitivity in this method, and the entire analysis process is within 18 min. In addition, the proposed method maintains linearity in the calibration curve from 50 to 2,000 ng/mL (r(2) > 0.995). The limit of detection of this method is 5 ng/mL, with the exception of MDPV (20 ng/mL); the limit of quantification is 20 ng/mL, with the exception of MDPV (50 ng/mL). In testing, the extraction performance of SPE was between 82.34 and 104.46%. Precision and accuracy results were satisfactory <15%. The proposed method was applied to six real urine samples, one of which was found to contain 4-MMC and bk-MDMA. Our results demonstrate the efficacy of the proposed method in the identification of synthetic cathinones in urine, with regard to the limits of detection and quantification. This method is highly repeatable and accurate.


Assuntos
Drogas Desenhadas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Detecção do Abuso de Substâncias/métodos , 3,4-Metilenodioxianfetamina/análogos & derivados , 3,4-Metilenodioxianfetamina/urina , Acetona/análogos & derivados , Acetona/urina , Anfetaminas/urina , Benzodioxóis/urina , Calibragem , Etilaminas/urina , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Limite de Detecção , Metanfetamina/análogos & derivados , Metanfetamina/urina , Pirrolidinas/urina , Reprodutibilidade dos Testes , Extração em Fase Sólida , Detecção do Abuso de Substâncias/normas , Urinálise , Catinona Sintética
19.
Artigo em Inglês | MEDLINE | ID: mdl-26076046

RESUMO

An efficient non-target dye-screening system consisting of a liquid chromatography photodiode array coupled with a high-resolution mass spectrometer (HRMS) is described. Visible absorption spectroscopy assisted in locating the peak of an unknown dye in HRMS chromatograms which allowed the accurate molecular weight of the unknown to be obtained. In a study of the adulteration of processed soymilk curd (tofu) with dimethyl yellow, an unexpected unknown dye was discovered. The compound was further purified by gel permeation chromatography and identified by HRMS and proton nuclear magnetic resonance (NMR) as diethyl yellow (solvent yellow 56). This is the first time that diethyl yellow has been reported in foods. The authentic diethyl yellow was then purchased and used as a quantitative standard. Tofu products and their ingredients associated with tofu processing were surveyed. Analysis showed the source of diethyl yellow could be traced to emulsifiers used as ingredient in tofu products. Surveillance work found the concentrations of diethyl yellow ranged from several µg kg(-1) (ppb) in the tofu products to up to hundreds of mg kg(-1) (ppm) in the emulsifiers.


Assuntos
Derivados de Benzeno/isolamento & purificação , Corantes/isolamento & purificação , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Espectrometria de Massas/métodos , Alimentos de Soja/análise , Cromatografia em Gel , Emulsificantes/química , Análise de Alimentos/instrumentação , Inocuidade dos Alimentos , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/instrumentação , Peso Molecular , Taiwan
20.
Artigo em Inglês | MEDLINE | ID: mdl-26010536

RESUMO

Cu-pyropheophytin a, the major Cu-pigment of Cu-chlorophyll, was determined in edible oil by high-resolution mass spectrometry with a high-performance liquid chromatography-quadrupole (HPLC-Q)-Orbitrap system and by HPLC coupled with a photodiode-array detector. Respective limit of detection and limit of quantification levels of 0.02 µg/g and 0.05 µg/g were obtained. Twenty-nine commercial oil products marked as olive oil, grapeseed oil and blended oil, all sourced directly from a food company that committed adulteration with Cu-chlorophyll, were investigated. In this company, four green dyes illegally used in oils were seized during factory investigation by the health authorities. The food additive Cu-pyropheophytin a was found in all confiscated samples in concentrations between 0.02 and 0.39 µg/g. Survey results of another 235 commercial oil samples manufactured from other companies, including olive pomace oil, extra virgin olive oil, olive oil, grapeseed oil and blended oil, indicated high positive incidences of 63%, 39%, 44%, 97% and 8%, respectively, with a concentration range between 0.02 and 0.54 µg/g. High Cu-chlorophyll concentrations are indications for fraudulent adulteration of oils.


Assuntos
Clorofilídeos/análise , Gorduras Insaturadas na Dieta/análise , Corantes de Alimentos/análise , Contaminação de Alimentos , Inspeção de Alimentos/métodos , Óleos de Plantas/química , Clorofila/análogos & derivados , Clorofila/análise , Cromatografia Líquida de Alta Pressão , Gorduras Insaturadas na Dieta/economia , Indústria de Processamento de Alimentos/economia , Frutas/química , Guias como Assunto , Resíduos Industriais/análise , Resíduos Industriais/economia , Limite de Detecção , Azeite de Oliva/química , Azeite de Oliva/economia , Azeite de Oliva/normas , Feofitinas/análise , Fotometria , Óleos de Plantas/normas , Sementes/química , Espectrofotometria Ultravioleta , Taiwan , Espectrometria de Massas em Tandem , Vitis/química
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