scholarly journals Adulteration of Weight Loss Supplements by the Illegal Addition of Synthetic Pharmaceuticals

Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6903
Author(s):  
Ammar A. Jairoun ◽  
Sabaa Saleh Al-Hemyari ◽  
Moyad Shahwan ◽  
Sa’ed H. Zyoud
Keyword(s):  
Weight Loss ◽  
United Arab Emirates ◽  
Health Risks ◽  
High Performance ◽  
Reversed Phase ◽  
Prescription Medications ◽  
Pharmaceutical Drugs ◽  
Herbal Supplements ◽  
Toxic Compounds ◽  
Rp Hplc

Weight loss supplements that have illegal additives of pharmaceutical drugs or analogues have additional health risks, and customers may not be aware of what they are taking. This research is an essential investigation and quantification of illegally added pharmaceuticals or prescription medications, specifically fluoxetine, phenolphthalein, and sibutramine, in herbal weight loss supplements offered for sale in the United Arab Emirates (UAE). In this case, 137 weight loss supplements were collected and analyzed in this study. Reversed-phase high-performance liquid chromatography with UV absorption detection coupled to tandem mass spectrometry (RP-HPLC-MS/MS) analyses were used to determine the presence of the pharmaceutical chemicals. Among the weight loss supplements, 15.3% (95% CI: 9.2–21.4) contained undeclared sibutramine, 13.9% (95% CI: 8.01–19.7) contained undeclared phenolphthalein, and 5.1% (95% CI: 1.4–8.8) contained undeclared fluoxetine. Amongst all weight loss supplements, 17.5% (95% CI: 11.07–24) contained significant concentrations of either sibutramine, phenolphthalein, or fluoxetine. Whilst weight loss herbal supplements offered for sale in the UAE have relatively low percentages of undeclared pharmaceuticals, many people take several different supplements daily and may encounter quite high levels of combined exposure to toxic compounds.

QBD ASSISTED RP-HPLC METHOD FOR IDENTIFICATION OF TERAZOSIN IN BULK DRUG AND PHARMACEUTICAL SAMPLE

INDIAN DRUGS ◽  
2018 ◽  
Vol 55 (03) ◽  
pp. 19-26
Author(s):  
C. Dhal ◽  
◽  
D. Rajput ◽  
V. Tiwari ◽  
A. Teotia ◽  
...  
Keyword(s):  
High Performance ◽  
High Performance Liquid Chromatographic ◽  
Reversed Phase ◽  
Hplc Method ◽  
Forced Degradation ◽  
Pharmaceutical Drugs ◽  
Reliable Technique ◽  
Rp Hplc ◽  
Bulk Drug ◽  
Liquid Chromatographic

Reversed Phase High Performance Liquid Chromatographic (RP-HPLC) proves to be a convenient and reliable technique for the identification of various compounds, such as pharmaceutical drugs of chemical as well as phyto origin, food compounds and others. Analytical method for the estimation of alpha-1 antagonist terazosin, a potent anti-hypertensive agent for enlarged prostate, was developed, optimized for the best fit condition using statistical software Minitab and validated as per International Conference on Harmonization (ICH) Q2 (R1) guidelines. Partitioning of the desired molecule was achieved on Agilent Zorbax C18 column with dimensions of 250 mm X 4.6 mm and a particle size 5μm against mobile phase containing acetate buffer adjusted to pH 6.0 and acetonitrile (ACN) in a ratio 30:70 (V/V), run isocratically for sufficient time. The linear model was established between 50 – 250 ppm with a regression coefficient (r2) of 0.9971 and with detection (LOD) and quantification limit (LOQ) of 17.754 ppm and 53.802 ppm, respectively. The method was precise, accurate, robust and able to distinguish between the adduct generated during forced degradation studies.

scholarly journals Development and validation of RP-HPLC method for estimation of brexpiprazole in its bulk and tablet dosage form using Quality by Design approach

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Amol S. Jagdale ◽  
Nilesh S. Pendbhaje ◽  
Rupali V. Nirmal ◽  
Poonam M. Bachhav ◽  
Dayandeo B. Sumbre
Keyword(s):  
Flow Rate ◽  
High Performance ◽  
Reversed Phase ◽  
Hplc Method ◽  
Control Analysis ◽  
Uv Detector ◽  
Mobile Phase Flow Rate ◽  
Rp Hplc ◽  
Quality By Design Approach ◽  
Bulk Drug

Abstract Background A new, sensitive, suitable, clear, accurate, and robust reversed-phase high-performance liquid chromatography (RP-HPLC) method for the determination of brexpiprazole in bulk drug and tablet formulation was developed and validated in this research. Surface methodology was used to optimize the data, with a three-level Box-Behnken design. Methanol concentration in the mobile phase, flow rate, and pH were chosen as the three variables. The separation was performed using an HPLC method with a UV detector and Openlab EZchrom program, as well as a Water spherisorb C18 column (100 mm × 4.6; 5m). Acetonitrile was pumped at a flow rate of 1.0 mL/min with a 10 mM phosphate buffer balanced to a pH of 2.50.05 by diluted OPA (65:35% v/v) and detected at 216 nm. Result The developed RP-HPLC method yielded a suitable retention time for brexpiprazole of 4.22 min, which was optimized using the Design Expert-12 software. The linearity of the established method was verified with a correlation coefficient (r2) of 0.999 over the concentration range of 5.05–75.75 g/mL. For API and formulation, the percent assay was 99.46% and 100.91%, respectively. The percentage RSD for the method’s precision was found to be less than 2.0%. The percentage recoveries were discovered to be between 99.38 and 101.07%. 0.64 μg/mL and 1.95 μg/mL were found to be the LOD and LOQ, respectively. Conclusion The developed and validated RP-HPLC system takes less time and can be used in the industry for routine quality control/analysis of bulk drug and marketed brexpiprazole products. Graphical abstract

SELECTION OF COLUMN AND OPERATING CONDITIONS FOR REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY OF PROTEINS IN CANADIAN WHEAT

1985 ◽  
Vol 65 (2) ◽  
pp. 285-298 ◽  
Author(s):  
J. E. KRUGER ◽  
B. A. MARCHYLO
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Storage Proteins ◽  
Sodium Dodecyl ◽  
Reversed Phase ◽  
Operating Conditions ◽  
Protein Patterns ◽  
Optimal Separation ◽  
Rp Hplc

Chromatographic conditions were optimized and three commercially available columns were evaluated for separation of alcohol-soluble storage proteins of Neepawa wheat using reversed-phase high-performance liquid chromatography (RP-HPLC). Optimal separation was achieved using an extracting solution of 50% 1-propanol, 1% acetic acid, and 4% dithiothreitol and an HPLC elution time of 105 min at a flow rate of 1.0 mL/min. HPLC columns evaluated (SynChropak RP-P, Ultrapore RPSC and Aquapore RP-300) varied in selectivity and resolution. The column providing the greatest versatility was Aquapore RP-300 available in cartridge form. Sodium dodecyl sulfate gradient-gel electrophoresis analysis of protein peaks resolved by RP-HPLC indicated that many of the eluted peaks contained more than one protein species. Chromatographic protein patterns obtained for Neepawa wheat grown at different locations and in different years were qualitatively the same.Key words: Protein, high-performance liquid chromatography, wheat

Standardisation of Artemisia annua using Reversed Phase High Performance Liquid Chromatography (RP-HPLC).

2010 ◽  
Vol 2 (7) ◽  
pp. 142-147
Author(s):  
O. Amos Abolaji ◽  
M. Ubana Eteng ◽  
E. Patrick Ebong ◽  
Andi Brisibe ◽  
Ahmed Shakil ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Artemisia Annua ◽  
Reversed Phase ◽  
Rp Hplc

scholarly journals RP-HPLC measurement and quantitative structure - property relationship analysis of the n-octanol - water partitioning coefficients of selected metabolites of polybrominated diphenyl ethers

2008 ◽  
Vol 5 (5) ◽  
pp. 332 ◽  
Author(s):  
Yijun Yu ◽  
Weihua Yang ◽  
Zishen Gao ◽  
Michael H. W. Lam ◽  
Xiaohua Liu ◽  
...  
Keyword(s):  
Polybrominated Diphenyl Ethers ◽  
High Performance ◽  
Reversed Phase ◽  
Retention Indices ◽  
Quantitative Structure ◽  
Structure Property ◽  
Rp Hplc ◽  
Structure Property Relationship ◽  
Water Partitioning ◽  
Log Kow

Environmental context. Polybrominated diphenyl ethers (PBDEs) are ubiquitous environmental contaminants and numerous studies have demonstrated a marked increase in the levels of PBDEs in human biological tissues and fluids, especially breast milk. How PBDEs are transported through the environment, taken up by biota, transported across membranes, and metabolised depends strongly on such fundamental properties as lipophilicity (log KOW). However, very little data on log KOW exist for PBDEs. In the present paper, the authors determine PBDE metabolites’ log KOW using reversed-phase high performance liquid chromatography, as recommended by the Organisation for Economic Co-operation and Development and US Environmental Protection Agency, along with quantitative structure–property relationships. Abstract. n-Octanol–water partitioning coefficient (log KOW) values of selected hydroxylated and methoxylated polybrominated diphenyl ether metabolites were measured for the first time by reversed-phase high performance liquid chromatography (RP-HPLC) using a C18 stationary phase with a water/methanol mixture as a mobile phase. The retention parameters, log kw (extrapolated retention indices) and k′ (gradient retention indices) were calibrated to log KOW by a set of calibration standards. For the PBDE metabolites investigated, extrapolated retention indices from isocratic elution seem to be more reliable and their RP-HPLC-derived log KOW values were found to range from 4.63 to 7.67. Some commonly available software, including ClogP, KowWin, AclogP, MlogP, AlogP, MilogP, and XlogP, was used to estimate the log KOW values of the analytes. Significant correlations were obtained between the RP-HPLC-derived log KOW and the software-computed log KOW, with squared correlation coefficients (R2) ranging from 0.793 to 0.922, but the difference between them was also significant. Then a quantitative structure–property relationship model based on topological descriptors was established and showed good reliability and predictive power for the estimation of RP-HPLC-derived log KOW values of PBDE metabolites. It was applied to estimate the log KOW values of some PBDE metabolites that are commercially available or have appeared in the literature. Lastly, factor analysis was carried out using the theoretical linear salvation/free-energy relationships, which indicated the average polarisability (α) and the most negative atomic partial Mulliken charge in the molecule (q–) were the most important parameters affecting their partition between n-octanol and water, supporting the factorisation of log KOW in bulk and electronic terms.

BIO ANALYTICAL METHOD DEVELOPMENT AND VALIDATION FOR SIMULANEOUS ESTIMATION OF NITAZOXANIDE AND OFLOXACIN IN HUMAN PLASMA BY RP-HPLC

INDIAN DRUGS ◽  
2021 ◽  
Vol 57 (10) ◽  
pp. 47-57
Keyword(s):  
Human Plasma ◽  
High Performance ◽  
Method Development ◽  
Reversed Phase ◽  
Chromatography Method ◽  
Rp Hplc ◽  
Method Development And Validation ◽  
Liquid Chromatography Method ◽  
Development And Validation ◽  
Lower Limits

An isocratic Reversed-Phase High Performance Liquid Chromatography method has been developed for rapid and simultaneous separation and estimation of two antibiotics, namely, nitazoxanide and ofloxacin, in human plasma. Separation was carried out on Altima C8 (150 x 4.6 mm, 5µ) column using a mobile phase of 0.1% ortho phosphoric acid: acetonitrile (50:50, V/V) at 260 nm. The retention time of nitazoxanide and ofloxacin was noted to be 4.850 and 7.949 min, respectively. The average % recovery for nitazoxanide and ofloxacin were 98.012 % and 94.176 %, respectively and reproducibility was found to be satisfactory. The linearity was investigated in the concentration range of 0.02-2 µg/ml (r2=0.9996) for nitazoxanide and 0.008-0.8 µg/ml (r2=0.9998) for ofloxacin. The lower limits of quantification were 0.0196 µg/ml and 0.0079 µg/ml for nitazoxanide and ofloxacin, respectively, which reach the level of both drugs possibly found in human plasma. The proposed method can be applied for etermination of nitazoxanide and ofloxacin from dosage forms during pharmacokinetic study.

scholarly journals Development and validation of reversed phase high performance liquid chromatography (RP-HPLC) for quantification of captopril in rabbit plasma

2020 ◽  
Author(s):  
Muhammad Fawad Rasool ◽  
Umbreen Fatima Qureshi ◽  
Nazar Muhammad Ranjha ◽  
Imran Imran ◽  
Mouqadus Un Nisa ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Mobile Phase ◽  
High Performance ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
Rabbit Plasma ◽  
Rp Hplc ◽  
Relative Standard

AbstractTh accurate rapid, simple and selective reversed phase high performance liquid chromatography (RP-HPLC) has been established and validated for the determination of captopril (CAP). Chromatographic separation was accomplished using prepacked ODSI C18 column (250 mm × 4.6 mm with 5 μm particle size) in isocratic mode, with mobile phase consisting of water: acetonitrile (60:40 v/v), pH adjusted to 2.5 by using 85% orthophosphoric acid at a flow rate of 1 mL/min and UV detection was performed at 203 nm. RP-HPLC method used for the analysis of CAP in mobile phase and rabbit plasma was established and validated as per ICH-guidelines. It was carried out on a well-defined chromatographic peak of CAP was established with a retention time of 4.9 min and tailing factor of 1.871. The liquid–liquid extraction method was used for extraction of CAP from the plasma. Excellent linearity (R2 = 0.999) was shown over range 3.125–100 µg/mL with mean percentage recoveries ranges from 97 to 100.6%. Parameters of precision and accuracy of the developed method meet the established criteria. Intra and inter-day precision (% relative standard deviation) study was also performed which was less than 2% which indicate good reproducibility of the method. The limit of detection (LOD) and quantification for the CAP in plasma were 3.10 and 9.13 ng/mL respectively. The method was suitably validated and successfully applied to the determination of CAP in rabbit plasma samples.

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