Detection of Synthetic Drugs as Adulterants in Natural and Herbal Slimming Products by LC-ESI-MS/MS with Polarity Switching

2016 ◽  
Vol 99 (4) ◽  
pp. 929-940 ◽  
Author(s):  
Phyllis Wilson ◽  
Claude Masse
Keyword(s):  
Weight Loss ◽  
Simultaneous Detection ◽  
Gradient Elution ◽  
Ammonium Formate ◽  
Synthetic Drugs ◽  
Polarity Switching ◽  
Validation Parameters ◽  
Wide Range ◽  
Aqueous Component ◽  
Positive Mode

Abstract The purpose of this study was to develop an LC-tandem MS method for the simultaneous detection of common synthetic drugs as adulterants in natural and herbal slimming products. Sixteen drugs belonging to a wide range of pharmaceutical classes were studied. Included in the list of drugs were anorexics, anxiolytics, antidepressants, diuretics, laxatives, and stimulants. The method used a C18 column (4.6 × 50 mm and 1.8 μm particle size). Separation of the drugs was achieved by gradient elution using 4 mM ammonium formate in water + 0.1% formic acid as the aqueous component and 4 mM ammonium formate in methanol + 0.1% formic as the organic component of the mobile phase. As not all of the analytes ionized in the positive mode, the mass spectrometer was operated in the electrospray ionization mode with polarity switching. The samples were extracted with methanol and the use of 50% acetonitrile in water and 50% methanol in water were investigated as diluents for injection into the LC-MS system. Utilizing both diluents, the validation parameters including accuracy, precision, LOD, and LOQ were assessed. The validation results and utilization of the method to analyze a variety of weight-loss supplements indicate that the two diluents give similar results and can be used interchangeably. This knowledge provides the user with the option of selecting either diluent for sample preparation depending on the sample matrix without having to revalidate the method. The method was applied to the analysis of weight-loss supplements available in local pharmacies, herbal pharmacies, and over the Internet.

scholarly journals Gradient HPLC in the determination of drug lipophilicity and acidity

2001 ◽  
Vol 73 (9) ◽  
pp. 1465-1475 ◽  
Author(s):  
Roman Kaliszan ◽  
Piotr Haber ◽  
Tomasz Baczek ◽  
Danuta Siluk
Keyword(s):  
Mobile Phase ◽  
High Performance ◽  
Standard Procedure ◽  
Gradient Elution ◽  
Log P ◽  
Retention Data ◽  
Organic Modifier ◽  
Wide Range ◽  
Aqueous Component ◽  
Initial Ph

The linear-solvent strength (LSS) model of gradient elution in high-performance liquid chromatography (HPLC) has been demonstrated to provide parameters of lipophilicity and acidity of analytes. pKa and log kw values are determined in three gradient runs. The first two experiments use an aqueous buffered eluent with a wide-range organic modifier gradient at pH of buffer, providing suppression of ionization of the analyte. That experiment allows an estimate of contents of the organic modifier in the mobile phase (%B), producing requested retention coefficient, k, for the nonionized form of the analyte. The next experiment is carried out with the latter %B and a pH-gradient of the aqueous component of the eluent that is sufficient to overlap possible pKa value of the analyte. The initial pH of the buffer used to make the mobile phase is selected to insure that the analyte is in nonionized form. The resulting retention time allows an estimate of pKa in a solvent of the given %B.The log kw parameter obtained correlated well with the corresponding value obtained by the standard procedure of extrapolation of retention data determined in a series of isocratic measurements. The correlation between log kw and the reference parameter of lipophilicity, log P, was very good for a series of test analytes. The values of pKa were found to correlate with the literature pKa data determined in water for a set of aniline derivatives studied.

scholarly journals Tribological Aspects, Optimization and Analysis of Cu-B-CrC Composites Fabricated by Powder Metallurgy

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4217
Author(s):  
Üsame Ali Usca ◽  
Mahir Uzun ◽  
Mustafa Kuntoğlu ◽  
Serhat Şap ◽  
Khaled Giasin ◽  
...  
Keyword(s):  
Weight Loss ◽  
Wear Rate ◽  
Coefficient Of Friction ◽  
Applied Load ◽  
Practical Significance ◽  
Tribological Characteristics ◽  
M 10 ◽  
Wide Range ◽  
The Coefficient Of Friction ◽  
Four Levels

Tribological properties of engineering components are a key issue due to their effect on the operational performance factors such as wear, surface characteristics, service life and in situ behavior. Thus, for better component quality, process parameters have major importance, especially for metal matrix composites (MMCs), which are a special class of materials used in a wide range of engineering applications including but not limited to structural, automotive and aeronautics. This paper deals with the tribological behavior of Cu-B-CrC composites (Cu-main matrix, B-CrC-reinforcement by 0, 2.5, 5 and 7.5 wt.%). The tribological characteristics investigated in this study are the coefficient of friction, wear rate and weight loss. For this purpose, four levels of sliding distance (1000, 1500, 2000 and 2500 m) and four levels of applied load (10, 15, 20 and 25 N) were used. In addition, two levels of sliding velocity (1 and 1.5 m/s), two levels of sintering time (1 and 2 h) and two sintering temperatures (1000 and 1050 °C) were used. Taguchi’s L16 orthogonal array was used to statistically analyze the aforementioned input parameters and to determine their best levels which give the desired values for the analyzed tribological characteristics. The results were analyzed by statistical analysis, optimization and 3D surface plots. Accordingly, it was determined that the most effective factor for wear rate, weight loss and friction coefficients is the contribution rate. According to signal-to-noise ratios, optimum solutions can be sorted as: the highest levels of parameters except for applied load and reinforcement ratio (2500 m, 10 N, 1.5 m/s, 2 h, 1050 °C and 0 wt.%) for wear rate, certain levels of all parameters (1000 m, 10 N, 1.5 m/s, 2 h, 1050 °C and 2.5 wt.%) for weight loss and 1000 m, 15 N, 1 m/s, 1 h, 1000 °C and 0 wt.% for the coefficient of friction. The comprehensive analysis of findings has practical significance and provides valuable information for a composite material from the production phase to the actual working conditions.

scholarly journals Development and Validation of a Sensitive, Specific and Reproducible UPLC-MS/MS Method for the Quantification of OJT007, A Novel Anti-Leishmanial Agent: Application to a Pharmacokinetic Study

2021 ◽  
Vol 18 (9) ◽  
pp. 4624
Author(s):  
Maria Rincon Nigro ◽  
Jing Ma ◽  
Ololade Tosin Awosemo ◽  
Huan Xie ◽  
Omonike Arike Olaleye ◽  
...  
Keyword(s):  
Formic Acid ◽  
High Performance ◽  
Leishmania Major ◽  
Internal Standard ◽  
Gradient Elution ◽  
Rat Plasma ◽  
The Matrix ◽  
Liquid Chromatography Tandem Mass ◽  
Positive Mode ◽  
Acquity Uplc

OJT007 is a methionine aminopeptidase 1 (MetAP1) inhibitor with potent anti-proliferative effects against Leishmania Major. In order to study its pharmacokinetics as a part of the drug development process, a sensitive, specific, and reproducible ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated. Voriconazole was used as the internal standard to generate standard curves ranging from 5 to 1000 ng/mL. The separation was achieved using a UPLC system equipped with an Acquity UPLC BEH C18 column (2.1 × 50 mm, 1.7 μm) with 0.1% formic acid in acetonitrile and 0.1% formic acid in water as the mobile phase under gradient elution at a flow rate of 0.4 mL/min. The mass analysis was performed with a 4000 QTRAP® mass spectrometer using multiple-ion reaction monitoring (MRM) in the positive mode, with the transition of m/z 325 → m/z 205 for OJT007 and m/z 350 → m/z 101 for voriconazole. The intra- and inter-day precision and accuracy were within ±15%. The mean extraction recovery and the matrix effect were 95.1% and 7.96%, respectively, suggesting no significant matrix interfering with the quantification of the drug in rat plasma. This study was successfully used for the pharmacokinetic evaluation of OJT007 using the rat as an animal model.

scholarly journals DETERMINATION OF SULFONAMIDES IN CHICKEN MEAT BY SOLID PHASE EXTRACTION AND HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

1970 ◽  
Vol 63 ◽  
Author(s):  
C. T. Matea ◽  
C. Bele ◽  
F. Dulf
Keyword(s):  
High Performance ◽  
Ammonium Acetate ◽  
Solid Phase ◽  
Simultaneous Detection ◽  
Gradient Elution ◽  
Normal Phase ◽  
Chicken Meat ◽  
Liquid Liquid Extraction ◽  
Halogenated Solvents

This paper describes a method for the simultaneous detection and quantification of six sul-fonamides in chicken meat using normal phase cartridge clean-up and HPLC with UV detection . A liquid – liquid extraction and Sep- Pak silica clean-up procedure which minimizes the presence of halogenated solvents was used for sample preparation . The HPLC determination was performed using a RP C 18 column and sulfonamides were detected at 266 nm. Mobile phase was 0.01 M ammonium acetate pH 4.6 ( A ) and methanol ( B). Chromatographic separation was obtained by gradient elution ( 22 % B to 50 % within 17 min , back to 22 % in 2 min, equilibration for 5 min).Average recoveries of analytes from spiked meat were higher than 74 % .

scholarly journals Development and validation of the method for the quantitative determination of methotrexate in a transport medium by HPLC-MS/MS

2021 ◽  
pp. 45-51
Author(s):  
P. Yu. Mylnikov ◽  
Yu. Tranova ◽  
A. V. Shchulkin ◽  
E. N. Yakusheva
Keyword(s):  
Quantitative Determination ◽  
Gradient Elution ◽  
Sample Volume ◽  
Transport Medium ◽  
Mass Selective Detector ◽  
Transporter Protein ◽  
Wide Range ◽  
Separation Temperature

Relevance. BCRP is an efflux transporter protein that plays an important role in the pharmacokinetics of a wide range of drugs. The BCRP activity in vitro experiments is assessed by the transport of transporter protein substrates (methotrexate, etc.) across the bilipid membrane of cells overexpressingBCRP, for example, Caco-2 cells. The aim is to develop and validate a method for the quantitative determination of the BCRP substrate, methotrexate, in the transport medium of Caco-2 cells by HPLC-MS/MS. Methods. The work was performed on an Ultimate 3000 HPLC chromatograph (ThermoFisher, USA) with a TSQ Fortis tandem mass-selective detector (ThermoFisher, USA). The conditions of chromatographic analysis were as follows: column UCT Selectra C18 4.6 mm * 100 mm 5um, 100A, Selectra C18 Guard Cartridges SLC-18GDC46-5UM, separation temperature 35 °С, flow rate 0.3 ml/min, injected sample volume - 2 μl, analysis time - 10 min. Used a gradient elution: the ratio of the solution of 0.1 % formic acid and acetonitrile was at 0 min 75 and 25 %; 0.4 min 60 and 40 %; 6 minutes 20 and 80 %; 8 minutes 75 and 25 %. Under these conditions, the retention time of methotrexate is 3.11 minutes. Detection conditions: methotrexate - positive ionization mode, 455.15 m / z → 308.125 m / z, collision energy 22.99 V, source fragmentation 5, CID gas pressure 2 mTorr. The extraction of methotrexate from the transport medium (Hanks solution with 25 mM Hepes and 1% dimethyl sulfoxide) after incubation with Caco-2 cells for 3 h was carried out with a mixture of methanol + water in a ratio of 1: 1. Results. The developed method was validated according to the following parameters: selectivity, linearity, accuracy, precision, limit of quantitative determination, sample transfer, sample stability. The confirmed analytical range of the method was 60 -10,000 nmol / L in the transport medium. Conclusions: a method for the quantitative determination of methotrexate in the transport medium of Caco-2 cells by HPLC-MS / MS was developed and validated.

scholarly journals Elements Identification in Golden Strawberries (Physalis Peruviana L.) using Wavelength Dispersive X-Ray Fluorescence

2019 ◽  
Vol 7 (6) ◽  
pp. 851
Author(s):  
Uğur Akbaba
Keyword(s):  
Weight Loss ◽  
Functional Food ◽  
Medical Field ◽  
X Ray ◽  
Physalis Peruviana ◽  
Food Properties ◽  
Wide Range ◽  
Important Health ◽  
Fluorescence Spectrometer ◽  
Non Destructive

Physalis peruviana (PP) is a popular exotic fruit due to its functional food properties. This product has a wide range of uses in the medical field, including treatments for cancer, malaria, hepatitis, dermatitis, rheumatism, weight loss, and diabetes. In this study, the PP element concentrations were investigated using a Wave Dispersive X-ray Fluorescence Spectrometer (WDXRF). Al, Ca, Fe, Mn, P, S, Zn, Cl, K, Mg, Na, F, Si, and B were detected, and the Ca, Fe, Zn, P, Na, Mg elements were found in significant amounts. Therefore, PP has some important health elements. For example, Mg and Mn may be associated with diabetes control. WDXRF is a cheap, quick, and non-destructive technique used in the elemental analysis of plant samples.

Biological and medicinal application of Cucumis sativus Linn. – review of current status with future possibilities

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Anayatullah Khan ◽  
Anuradha Mishra ◽  
Syed Misbahul Hasan ◽  
Afreen Usmani ◽  
Mohd Ubaid ◽  
...  
Keyword(s):  
Cucumis Sativus ◽  
Cost Effective ◽  
Pharmacological Action ◽  
Modern Medicine ◽  
Current Status ◽  
Synthetic Drugs ◽  
Wide Range ◽  
Increasing Demand ◽  
Calcium Iron ◽  
Whole Plants

Abstract Objectives The increasing demand for herbal drugs for the human application is causing a growing demand for the cultivation of Medicinal Plants. This demand has developed because of cost-effective, plant-derived products rather than commercially available synthetic drugs. Cucumis sativus Linn. (Ver. Kheera) is a vegetable climber, species belongs to family Cucurbitaceae This species has a wide range of medicinal and biological applications thanks to its richness in carbohydrate, proteins, minerals (calcium, iron, magnesium, phosphorus, potassium, zinc) and secondary metabolites like alkaloids, tannins, flavonoids, saponins, and phenolic compounds These phytoconstituents may be responsible for allied therapeutic application. So, C. sativus possess wider applications for preventing certain ailments. Content The literature in various national and international journals and reports pertaining to the medicinal and nutritional uses were reviewed. The result revealed the current therapeutic applications of C. sativus whole plants other than the nutritional value. C. sativus pharmacological action includes antioxidant, anti-diabetic, UV protectant, hepatoprotective, gastroprotective, anti-helminthic, wound healing, antimicrobial, and anticancer. So, it could be useful for both preventive and additive therapy along with modern medicine for the better management of certain disorders. Summary and Outlook This review furnishes updated information about the phytoconstituents and their medicinal applications so that it can pose a path for the young researchers to do future findings.

Screening of 104 New Psychoactive Substances (NPS) and Other Drugs of Abuse in Oral Fluid by LC–MS-MS

2020 ◽  
Vol 44 (7) ◽  
pp. 697-707
Author(s):  
Kelly Francisco da Cunha ◽  
Karina Diniz Oliveira ◽  
Marilyn A Huestis ◽  
Jose Luiz Costa
Keyword(s):  
Oral Fluid ◽  
Drugs Of Abuse ◽  
Matrix Effects ◽  
Synthetic Cannabinoids ◽  
Screening Method ◽  
Simultaneous Detection ◽  
New Psychoactive Substances ◽  
Major Public Health Problem ◽  
Psychoactive Substances ◽  
Wide Range

Abstract New psychoactive substances (NPS) are a major public health problem, primarily due to the increased number of acute poisoning cases. Detection of these substances is a challenge. The aim of this research was to develop and validate a sensitive screening method for 104 drugs of abuse, including synthetic cannabinoids, synthetic cathinones, fentanyl analogues, phenethylamines and other abused psychoactive compounds (i.e., THC, MDMA, LSD and their metabolites) in oral fluid by liquid chromatography–tandem mass spectrometry (LC–MS-MS). The Quantisal™ oral fluid device was used to collect oral fluid samples. The oral fluid–elution buffer mixture (500-μL sample) was extracted with t-butyl methyl ether, and chromatographic separation was performed on a Raptor™ biphenyl column (100 × 2.1 mm ID, 2.7 μm), with a total run time of 13.5 min. Limits of detection were established at three concentrations (0.05, 0.1 or 1 ng/mL) for most analytes, except for acetyl norfentanyl and mescaline (5 ng/mL). Matrix effects were generally <20% and overall extraction recoveries >60%. The highest matrix effect was observed within the synthetic cannabinoid group (PB22, −55.5%). Lower recoveries were observed for 2C-T (47.2%) and JWH-175 (58.7%). Recoveries from the Quantisal™ device were also evaluated for all analytes (56.7–127%), with lower recoveries noted for 25I-NBOMe, valerylfentanyl and mCPP (56.7, 63.0 and 69.9%, respectively). Drug stability in oral fluid was evaluated at 15, 60 and 90 days and at 25, 4 and −20°C. As expected, greater stability was observed when samples were stored at −20°C, but even when frozen, some NPS (e.g., synthetic cannabinoids) showed more than 20% degradation. The method was successfully applied to the analysis of seven authentic oral fluid samples positive for 17 different analytes. The method achieved good sensitivity and simultaneous detection of a wide range of NPS.

scholarly journals Advancement of Nanobiomaterials to Deliver Natural Compounds for Tissue Engineering Applications

2020 ◽  
Vol 21 (18) ◽  
pp. 6752
Author(s):  
Sathish Sundar Dhilip Kumar ◽  
Heidi Abrahamse
Keyword(s):  
Tissue Engineering ◽  
Engineering Application ◽  
Natural Compounds ◽  
Treatment Modalities ◽  
Tissue Engineering Application ◽  
Engineering Applications ◽  
Synthetic Drugs ◽  
Medicinal Compounds ◽  
Wide Range ◽  
Clinical Benefits

Recent advancement in nanotechnology has provided a wide range of benefits in the biological sciences, especially in the field of tissue engineering and wound healing. Nanotechnology provides an easy process for designing nanocarrier-based biomaterials for the purpose and specific needs of tissue engineering applications. Naturally available medicinal compounds have unique clinical benefits, which can be incorporated into nanobiomaterials and enhance their applications in tissue engineering. The choice of using natural compounds in tissue engineering improves treatment modalities and can deal with side effects associated with synthetic drugs. In this review article, we focus on advances in the use of nanobiomaterials to deliver naturally available medicinal compounds for tissue engineering application, including the types of biomaterials, the potential role of nanocarriers, and the various effects of naturally available medicinal compounds incorporated scaffolds in tissue engineering.

scholarly journals Impact of hypocaloric dietary intervention on ovulation in obese women with PCOS

Reproduction ◽  
2017 ◽  
Vol 153 (1) ◽  
pp. R15-R27 ◽  
Author(s):  
Brittany Y Jarrett ◽  
Marla E Lujan
Keyword(s):  
Weight Loss ◽  
Dietary Intervention ◽  
Polycystic Ovary ◽  
Reproductive Function ◽  
Antral Follicle ◽  
Reproductive Age ◽  
Obese Women ◽  
Dietary Interventions ◽  
Wide Range ◽  
The Impact

Polycystic ovary syndrome (PCOS) is a common cause of ovulatory dysfunction affecting women of reproductive age. Obesity and insulin resistance are thought to potentiate disruptions in antral follicle development that result in chronic anovulation, and as such, have become important therapeutic targets of dietary interventions aimed at weight loss. Caloric restriction has been shown to promote sporadic ovulation in obese women with PCOS, but improvements have occurred across a wide range of patients and little has been garnered about the factors that distinguish responders from non-responders. Further, few studies have evaluated the likelihood for modest weight loss to restore normal ovulatory cyclicity in PCOS. Consensus regarding the impact of dietary intervention on ovulation has been limited by variability in the measures used to characterize and report ovulatory status across studies. In response, this review provides an assessment of the evidence surrounding the effectiveness of hypocaloric dietary intervention to normalize ovulatory function in PCOS. The impact of physiological vs methodological factors on the evaluation of ovulatory status is discussed, and recommendations to strengthen future studies in this area are provided. Ultimately, further research is needed to understand the optimal dietary or lifestyle approaches that promote ovulation and sustained improvements in reproductive function in PCOS.

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