scholarly journals Determination of Diazepam in Cream Biscuits by Liquid Chromatography

2004 ◽  
Vol 87 (3) ◽  
pp. 569-572 ◽  
Author(s):  
Priyankar Ghosh ◽  
Mudiam Mohanakrishna Reddy ◽  
Beedu Sashidhar Rao ◽  
Rajendra Kumar Sarin

Abstract An analytical procedure was developed for the detection and quantitation of diazepam in cream biscuits, which were used to commit crime. The method involves the extraction of diazepam with ethanol at room temperature, and the extract is filtered, evaporated to dryness, and redissolved in the mobile phase, methanol–acetonitrile–tetrahydrofuran–water (15 + 55 + 4 + 26, v/v). The separation is achieved on a C18 reversed-phase column with the mobile phase and diode array detection (λmax) at 230 nm. Medazepam is used as the internal standard is for quantification. The calibration plot for the determination of diazepam is based on linear regression analysis (y = 0.6687x + 0.0372; r2 = 0.995). The limit of detection for diazepam in the biscuit samples was estimated as 600 ng/mL. The limit of quantitation for diazepam was estimated as 1.75 μg/mL. The diazepam detected per piece of biscuit was found to be in the range of 0.27–0.45 mg. Pure diazepam was added to biscuit samples at 3 levels (100 and 500 μg/g, and 1 mg/g), and the recoveries were found to be 95%. The mean retention time of diazepam was 2.7 min and that of medazepam (IS) was 4 min. The relative standard deviations of the diazepam level in the biscuit samples were estimated to be 0.4% for retention time and 1.02% for peak area in intraday analysis, whereas the corresponding values were and 0.61 and 2.34% in interday analysis. The method is rapid and reliable for qualitative and quantitative analysis of cream biscuits laced with diazepam, and it can be used by law enforcement laboratories for routine analysis.

Pharmacia ◽  
2022 ◽  
Vol 69 (1) ◽  
pp. 21-24
Author(s):  
Stefan Balkanski

Purpose: A simple, specific, precise, and accurate reversed phase liquid chromatographic (RP-LC) method has been developed for the determination of Escitalopram in tablet dosage form. Methods: The chromatographic separation was achieved on a LiChrosorb C18, 250 mm x 4.6 mm, 5 μm column at a detector wavelength of 270 nm and a flow rate of 1.0 ml/min. The mobile phase was composed of methanol, acetonitrile (70:30 v/v). The retention time of Escitalopram was 5.49 min. The method was validated for the parameters like specificity, linearity, precision, accuracy, limit of quantitation and limit of detection. Results: The method was found to be specific as no other peaks of impurities and excipients were observed. The square of correlation coefficient (R2) was 0.9999 while relative standard deviations were found to be <2.0%. Conclusion: The proposed RP-LC method can be applied for the routine analysis of commercially available formulations of Escitalopram.


2017 ◽  
Vol 9 (2) ◽  
pp. 34
Author(s):  
N. Balaji ◽  
Sayeeda Sultana

Objective: An efficient, high performance liquid chromatographic method has been developed and validated for the quantification of related substances in pioglitazone hydrochloride drug substance.Methods: This method includes the determination of three related substances in pioglitazone hydrochloride. The mobile phase A is 0.1% w/v triethylamine in water with pH 2.5 adjusted by dilute phosphoric acid. The mobile phase B is premixed and degassed mixtures of acetonitrile and methanol. The flow rate was 1 ml/min. The elution used was gradient mode. The HPLC column used for the analysis was symmetry C18 with a length of 250 mm, the internal diameter of 4.6 mm and particle size of 5.0 microns.Results: The developed method was found to be linear with the range of 0.006-250% with a coefficient of correlation 0.99. The precision study revealed that the percentage relative standard deviation was within the acceptable limit. The limit of detection and limit of quantitation of the impurities was less than 0.002%and 0.006% with respect to pioglitazone hydrochloride test concentration of 2000 µg/ml respectively. This method has been validated as per ICH guidelines Q2 (R1).Conclusion: A reliable, economical HPLC method was magnificently established for quantitative analysis of related substances of pioglitazone hydrochloride drug substance.


Author(s):  
Muhammad Fawad Rasool ◽  
Umbreen Fatima Qureshi ◽  
Nazar Muhammad Ranjha ◽  
Imran Imran ◽  
Mouqadus Un Nisa ◽  
...  

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.


2007 ◽  
Vol 90 (3) ◽  
pp. 720-724
Author(s):  
Sevgi Tatar Ulu

Abstract A sensitive and selective high-performance liquid chromatographic method has been developed for the determination of tianeptine (Tia) in tablets. The method is based on derivatization of Tia with 4-chloro-7-nitrobenzofurazan (NBD-Cl). A mobile phase consisting of acetonitrile10 mM orthophosphoric acid (pH 2.5; 77 + 23) was used at a flow rate of 1 mL/min on a C18 column. The Tia-NBD derivative was monitored using a fluorescence detector, with emission set at 520 nm and excitation at 458 nm. Gabapentin was selected as an internal standard. Linear calibration graphs were obtained in the concentration range of 45300 ng/mL. The lower limit of detection (LOD) was 10 ng/mL at a signal-to-noise ratio of 4. The lower limit of quantitation (LOQ) was 45 ng/mL. The relative standard values for intra- and interday precision were <0.46 and <0.57%, respectively. The recovery of the drug samples ranged between 98.89 and 99.85%. No chromatographic interference from the tablet excipients was found. The proposed method was validated in terms of precision, robustness, recovery, LOD, and LOQ. All the validation parameters were within the acceptance range. The proposed method was applied for the determination of Tia in commercially available tablets. The results were compared with those obtained by an ultraviolet spectrophotometric method using t- and F-tests.


2009 ◽  
Vol 92 (1) ◽  
pp. 302-306 ◽  
Author(s):  
Xiao-Jing Yan ◽  
Xiao-Mei Liang ◽  
Yan-Jun Xu ◽  
Shu-Hui Jin ◽  
Dao-Quan Wang

Abstract A method was developed for the determination of 7B3 (12-propyloxyimino-1,15-pentadecanlactam), a novel macrolactam fungicide, by liquid chromatography/mass spectrometry (LC/MS) with positive electrospray ionization (ESI+). The method used a reversed-phase C18 column and acetonitrilewater (60 + 40, v/v) mobile phase. The quick, easy, cheap, effective, rugged, and safe method was used for extraction of 7B3 from cotton plants, which involved the extraction of 10 g homogenized sample with 10 mL acetonitrile, followed by the addition of 4 g anhydrous MgSO4 and 1.0 g NaCl. After centrifugation, 1 mL of the buffered acetonitrile extract was transferred into a tube containing 50 mg primary secondary amine sorbent and 100 mg anhydrous MgSO4. After shaking and centrifugation, the final extract was transferred to an autosampler vial for concurrent analysis by LC/MS. The results of 7B3 determined by LC/MS in the selective ion monitoring mode were linear, and the matrix effect of the method was evaluated. The average recoveries of 7B3 fortified at different levels were within 84.1100.2, and the relative standard deviations were <7.5 for all samples analyzed. The method limit of detection and the limit of quantitation values were 0.03 and 0.1 mg/kg, respectively. The proposed method was successfully applied to determine 7B3 residues in practical samples. This method is sensitive, accurate, reliable, simple, and safe.


2004 ◽  
Vol 87 (1) ◽  
pp. 123-128
Author(s):  
Paul Johns ◽  
Rosalyn Phillips ◽  
Lobat Dowlat

Abstract A method was developed for the direct determination of free methionine in soy-based infant formula, with analyte separation and quantitation by reversed-phase liquid chromatography (LC), and UV absorbance at 214 nm, respectively. Sample preparation required only dilution with mobile phase and syringe filtration. Using a 0.02M KH 2 PO 4 mobile phase (pH adjusted to 2.9 with 85% o-phosphoric acid) and 0.7 mL/min flow rate, methionine eluted at approximately 8 min, and total run time was 14 min after column regeneration with acetonitrile–water. System linearity was demonstrated as peak area versus analyte concentration, ranging from 80 to 120% of the formula specification for free methionine (r > 0.999, and all residuals <0.45%). Intermediate precision relative standard deviation values were <1.5% for ready-to-feed and reconstituted powder samples, and recoveries ranged from 98.0 to 103.5% for inter-method comparison with an amino acid analyzer method. The limit of quantitation was 3 mg methionine/L in the “as fed” infant formula. Despite the relatively weak UV absorptivity of methionine, the 214 nm signal was sufficiently intense in the 30–65 mg/L (201–436 μM) range to afford quantitation by peak area proportionation versus a 2-point external standard calibration. This direct UV detection after reversed-phase LC separation provides a simple and accurate method for determining free methionine without derivatization.


2019 ◽  
Vol 38 (2) ◽  
pp. 161
Author(s):  
Elif Mine Oncu Kaya

A sensitive Ultra-High Performance Liquid Chromatography (UHPLC)-fluorescence method was developed and validated for the determination of ochratoxin-A (OTA) in Turkish wine samples. Naphthalene was used as an internal standard in this study. OTA was separated on a C18 (3.0 mm × 100 mm × 1.8 µm) column and analyses were run under isocratic conditions, with a mobile phase consisting of water/acetonitrile/acetic acid (50:50:1, v/v/v). The flow rate and injection volume were 0.5 ml min−1 and 10 μl, respectively. The excitation and emission wavelengths were 330 nm and 460 nm for OTA, respectively, and 220 nm and 325 nm for internal standard, respectively. A solid-phase extraction (SPE) clean-up procedure on a C18 cartridge was used prior to the analysis of the wine samples by UHPLC. The developed method was validated with respect to linearity, precision, accuracy, limit of detection (LOD), limit of quantitation (LOQ), stability and robustness. The method presented good RSD (< 4 %) and recovery (102.6–105.2 %) values. The LOD and LOQ values were 0.01 ng ml–1 and 0.05 ng ml–1, respectively. All other parameters were acceptable. OTA amounts were found in the range of 2.72‒7.40 µg kg‒1 in the Turkish wine samples.


Author(s):  
Krishna R. Gupta ◽  
Sneha Shelke ◽  
Anvesha V. Ganorkar ◽  
Nishiben Patel ◽  
Milind J. Umekar

 The research work aims to develop a bioanalytical method using liquid chromatography and validated for the determination of canagliflozin by using an internal standard. Department of Pharmaceutical Chemistry, Smt. Kishoritai Bhoyar College of Pharmacy, New Kamptee, Nagpur (MS). Isocratic chromatography separation was achieved on an LC system with PDA detector on an ACE C18 (150mm× 4.6mm × 5µm) column using a mobile phase composition of acetonitrile: ammonium acetate buffer in the ration of 50:50 v/v (pH 4.5), orthophosphoric acid is used to adjust pH of mobile phase and the flow rate at 1.0ml/ min. and estimation was carried out at 291 nm. The retention time of a drug was 4.633 minutes. The method was validated for several parameters (specificity, linearity, precision, and accuracy) and also successfully applied for the pharmacokinetic in female rats. Calibration plot was linear (r2 > 0.9973) over the concentration range of 5-30 µg/ml for canagliflozin. The high recovery and low relative standard deviation (%RSD) confirm the suitability of the method. The result of Limit of Detection (LOD) and Limit of Quantitation (LOQ) were found to be 0.1099 μg/ml and 0.3331 μg/ml, respectively. The new RP-HPLC method can be conveniently adapted for examining canagliflozin concentration in rat plasma after oral administration.


Author(s):  
Rajesh Kumar Chawla ◽  
G S N Koteswara Rao ◽  
Umasankar Kulandaivelu ◽  
Siva Prasad Panda ◽  
Rajasekhar Reddy Alavala

Abstract Objective A selective and sensitive liquid chromatography–tandem mass spectrometer (LC–MS/MS) method has been developed for the quantification of 1,1-dimethyl-3-hydroxy-pyrrolidinium bromide impurity in glycopyrrolate oral solution. Materials and method The LC–MS/MS analysis was done on X Bridge HILIC (100 × 4.6 mm, 5 μm) analytical column, and the mobile phase used was10 mM ammonium formate with 0.2% formic acid as mobile phase-A and acetonitrile as mobile phase-B with a gradient programme of 5.0 min. The flow rate used was 1.2 mL/min. Triple quadrupole mass detector coupled to positive electrospray ionization operated in multiple reactions monitoring mode was used for the quantification at m/z 116.10 ± 0.5. Results Retention time of impurity was found ~3.2 min. The method was validated in terms of specificity, linearity, accuracy, precision, range, limit of detection, limit of quantitation (LOQ) and robustness. Relative standard deviation (RSD) for system suitability was found 1.3%. Calibration plot was linear over the range of 0.050–2.000 μg/mL. Limit of detection and limit of quantification were found 0.017 and 0.051 μg/mL, respectively. The intra- and inter-day precision RSD was 2.3% and the obtained recovery at LOQ to 200% was in between 86.7 and 107.4%. Conclusion The low RSD values and high recoveries of the method confirm the suitability of the method.


1994 ◽  
Vol 77 (2) ◽  
pp. 344-350 ◽  
Author(s):  
Heidi S Rupp ◽  
Robert K Munns ◽  
Austin R Long ◽  
Steven M Plakas

Abstract A liquid chromatographic (LC) method was developed for the simultaneous determination of nitro-furazone (NFZ), nitrofurantoin (NFT), and furazolidone (FZD) in catfish muscle tissue. The drugs were extracted from the tissue with acetonitrile, and the lipids were removed from the extract with hexane. The acetonitrile extract was evaporated by rotary evaporation, and the resultant drug residues were dissolved with LC mobile phase. The mixture was sonicated, centrifuged, and filtered. The drugs were determined by using LC with a Cie reversed-phase (ODS Hypersil) column, a mobile phase of acetonitrile–1 % aqueous acetic acid (25 + 75), and a photodiode array ultraviolet detector at 375 nm. NFZ, NFT, and FZD were each determined in catfish tissue at 5 fortification levels (80, 40, 20,10, and 5 ng drug/g tissue). Average recoveries of each of the 3 drugs at each level ranged from 70.7 to 101.5%, and relative standard deviations ranged from 2.2 to 18.6%. The limit of detection of each drug was approximately 1 ng drug/g tissue, and the limit of quantitation was 5 ng drug/g tissue. In the second part of the study, the method was used to determine nitrofuran residues incurred in catfish tissue. Live channel catfish were intravascularly dosed (10 mg/kg body wt) with NFZ to generate drug-incurred fish muscle tissue. Incurred NFZ levels exceeded 400 ng drug/g tissue at 2 h after dosing but decreased rapidly to approximately 1 ng drug/g tissue by 8 h after dosing, as determined by this method.


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