scholarly journals Quantitative analysis of benzodiazepines in vitreous humor by high-performance liquid chromatography

2016 ◽  
Vol 4 ◽  
pp. 205031211666624 ◽  
Author(s):  
Elham Bazmi ◽  
Behnam Behnoush ◽  
Maryam Akhgari ◽  
Leila Bahmanabadi
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Quantitative Analysis ◽  
High Performance ◽  
Limit Of Detection ◽  
Vitreous Humor ◽  
Liquid Extraction ◽  
Array Detector ◽  
Postmortem Changes ◽  
Liquid Liquid Extraction

Objective: Benzodiazepines are frequently screened drugs in emergency toxicology, drugs of abuse testing, and in forensic cases. As the variations of benzodiazepines concentrations in biological samples during bleeding, postmortem changes, and redistribution could be biasing forensic medicine examinations, hence selecting a suitable sample and a validated accurate method is essential for the quantitative analysis of these main drug categories. The aim of this study was to develop a valid method for the determination of four benzodiazepines (flurazepam, lorazepam, alprazolam, and diazepam) in vitreous humor using liquid–liquid extraction and high-performance liquid chromatography. Methods: Sample preparation was carried out using liquid–liquid extraction with n-hexane: ethyl acetate and subsequent detection by high-performance liquid chromatography method coupled to diode array detector. This method was applied to quantify benzodiazepines in 21 authentic vitreous humor samples. Linear curve for each drug was obtained within the range of 30–3000 ng/mL with coefficient of correlation higher than 0.99. Results: The limit of detection and quantitation were 30 and 100 ng/mL respectively for four drugs. The method showed an appropriate intra- and inter-day precision (coefficient of variation < 10%). Benzodiazepines recoveries were estimated to be over 80%. The method showed high selectivity; no additional peak due to interfering substances in samples was observed. Conclusion: The present method was selective, sensitive, accurate, and precise for the quantitative analysis of benzodiazepines in vitreous humor samples in forensic toxicology laboratory.

Maceration-Mediated Liquid–Liquid Extraction and Reverse-Phase High-Performance Liquid Chromatography-Based Pragmatic Analysis of Silybins

2020 ◽  
Vol 58 (8) ◽  
pp. 779-787
Author(s):  
Syeda Mariam Hasany ◽  
Rahila Huma ◽  
Sumia Akram ◽  
Rizwan Ashraf ◽  
Muhammad Mushtaq
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Limit Of Detection ◽  
Curcuma Longa ◽  
Liquid Extraction ◽  
Reverse Phase ◽  
Limit Of Quantification ◽  
Liquid Liquid Extraction ◽  
Rp Hplc

Abstract This study presents a pragmatic and easily scalable maceration-mediated liquid–liquid extraction (MMLLE) and reverse-phase high-performance liquid chromatography (RP-HPLC)-based determination of Silybins from plant material (Curcuma longa L.). The processing of calibration standards revealed that the RP-HPLC method was linear over a concentration range of 1–100 μg/mL with regression coefficient (R2) &gt; 0.9950, limit of detection 0.02 μg/mL and limit of quantification &lt;0.07 μg/mL. The optimum chromatographic conditions resolved Silybin A, Silybin B, Isosilybin A and Isosilybin B within 5 min of analysis time. The reproducible recovery rates of spiked flavonolignans (96.24–115.40%) from quality controls established the effectiveness of MMLLE procedure prior to HPLC determination. The real-time analysis revealed the presence of silybins in C. longa roots. The results further endorse that MMLLE prior to chromatographic determination may provide a more pragmatic analytical solution for the analysis/isolation of silybins.

scholarly journals Intravascular Residence Time Determination for the Cyanide Antidote Dimethyl Trisulfide in Rat by Using Liquid-Liquid Extraction Coupled with High Performance Liquid Chromatography

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Deepthika De Silva ◽  
Steven Lee ◽  
Anna Duke ◽  
Siva Angalakurthi ◽  
Ching-En Chou ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Residence Time ◽  
Rat Model ◽  
High Performance ◽  
Liquid Extraction ◽  
Dimethyl Trisulfide ◽  
Liquid Liquid Extraction ◽  
Cyanide Antidote ◽  
Limit Of Quantitation

These studies represent the first report on the intravascular residence time determinations for the cyanide antidote dimethyl trisulfide (DMTS) in a rat model by using high performance liquid chromatography coupled with ultraviolet absorption spectroscopy (HPLC-UV). The newly developed sample preparation included liquid-liquid extraction by cyclohexanone. The calibration curves showed a linear response for DMTS concentrations between 0.010 and 0.30 mg/mL withR2= 0.9994. The limit of detection for DMTS via this extraction method was 0.010 mg/mL, and the limit of quantitation was 0.034 mg/mL. Thus this calibration curve provided a tool for determining DMTS in the range between 0.04 and 0.30 mg/mL. Rats were given 20 mg/kg DMTS dose (in 15% Polysorbate 80) intravenously, and blood samples were taken 15, 60, 90, 120, and 240 min after DMTS injections. The data points were plotted as DMTS concentration in RBCs versus time, and the intravascular residence time was determined graphically. The results indicated a half-life of 36 min in a rat model, suggesting that the circulation time is long enough to provide a reasonable time interval for cyanide antagonism.

scholarly journals ESTIMATION OF GUGGULSTERONE-Z IN GOKSHURADI GUGGULU USING REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

2018 ◽  
Vol 11 (11) ◽  
pp. 204
Author(s):  
Kanan G Gamit ◽  
Niraj Y Vyas ◽  
Nishit D Patel ◽  
Manan A Raval
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Limit Of Detection ◽  
Reversed Phase ◽  
Array Detector ◽  
Limit Of Quantification ◽  
Photodiode Array Detector ◽  
Validation Parameters ◽  
Photodiode Array

Objective: A study was aimed to estimate guggulsterone-Z (GZ) in Gokshuradi Guggulu (GG).Methods: An analytical method was developed and validated using Waters Alliance high-performance liquid chromatography system (Empower software), equipped with photodiode array detector. Separation was achieved using Phenomenex, C-18 (250 mm×4.6 mm, 5 μ) column. Mobile phase consisted of acetonitrile:water (70:30,v/v). Flow rate was set to 1 ml/min and detection was performed at 251 nm.Results and Discussion: Validation parameters such as linearity, precision, accuracy, limit of detection, limit of quantification, and robustness were performed. Amount of GZ was estimated using linearity equation.Conclusion: GG was found to contain 0.815±0.03 g% w/w GZ. Validated method may be used as one of the parameters to standardize the formulation.

scholarly journals Salting-out assisted liquid–liquid extraction coupled with high-performance liquid chromatography for the determination of vitamin D3 in milk samples

2019 ◽  
Vol 6 (8) ◽  
pp. 190952 ◽  
Author(s):  
Nur Hidayah Sazali ◽  
Anas Alshishani ◽  
Bahruddin Saad ◽  
Ker Yin Chew ◽  
Moi Me Chong ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Vitamin D3 ◽  
High Performance ◽  
Liquid Extraction ◽  
Sample Treatment ◽  
Salting Out ◽  
Milk Samples ◽  
Liquid Liquid Extraction

In this study, salting-out assisted liquid–liquid extraction (SALLE) as a simple and efficient extraction technique followed by high-performance liquid chromatography (HPLC) was employed for the determination of vitamin D3 in milk samples. The sample treatment is based on the use of water-miscible acetonitrile as the extractant and acetonitrile phase separation under high-salt conditions. Under the optimum conditions, acetonitrile and ammonium sulfate were used as the extraction solvent and salting-out agent, respectively. The vitamin D3 extract was separated using Hypersil ODS (250x i.d 4.6 mm, 5 µm) HPLC column that was coupled with diode array detector. Vitamin D2 was used as internal standard (IS) to offset any variations in chromatographic conditions. The vitamin D3 and the IS were eluted in 18 min. Good linearity ( r 2 > 0.99) was obtained within the range of 25–600 ng g −1 with the limit of detection of 15 ng g −1 and limit of quantification of 25 ng g −1 . The validated method was applied for the determination of vitamin D3 in milk samples. The recoveries for spiked samples were from 94.4 to 113.5%.

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