scholarly journals The Development and Validation of a Novel Designer Benzodiazepines Panel by LC–MS-MS

2021 ◽  
Author(s):  
Rebecca A Mastrovito ◽  
Donna M Papsun ◽  
Barry K Logan
Keyword(s):  
Illicit Drug ◽  
Liquid Extraction ◽  
Electrospray Tandem Mass Spectrometry ◽  
Method Performance ◽  
Internal Standards ◽  
Liquid Liquid Extraction ◽  
Relative Standard ◽  
Development And Validation ◽  
Positive Ion ◽  
Designer Benzodiazepines

Abstract Novel illicit benzodiazepines are among the most active areas of new illicit drug manufacture and use. We describe a method for the detection and quantification of etizolam and its metabolite α-hydroxyetizolam, flubromazolam, clonazolam, diclazepam, delorazepam, bromazepam, flubromazepam, phenazepam, flualprazolam, flunitrazolam, and nitrazolam in human whole blood. After addition of internal standards, samples are buffered and extracted using a liquid–liquid extraction. Analysis is performed using positive-ion electrospray tandem mass spectrometry for detection and quantitation. Calibration ranges were established based on the method performance and differed from compound to compound. Replicates at the lowest calibration point for each compound performed within 5% of CV (Coefficient of Variation). The correlation coefficient was >0.990 for all compounds. Relative standard deviation for all compounds was ≤10% of CV and accuracy was  ±10% for both within- and between-run experiments. The maximum average intra- and inter-run imprecision were 5.7%. The maximum average intra- and inter-run imprecision was −8.7%. As part of evaluating the scope for relevancy, samples testing positive in immunoassay but confirmed to be negative in traditional benzodiazepine confirmation method were re-analyzed using this method. The presence of at least one novel benzodiazepine was identified in 70% of these samples. The appearance of these novel “designer” benzodiazepines demonstrates the challenge for toxicology testing and the need for continually updated confirmation methods.

Development and Validation of UPLC-MS/MS Method for the determination of Rivaroxaban in human plasma using Liquid-liquid extraction

2021 ◽  
pp. 3239-3243
Author(s):  
Kailash Chander Malik ◽  
Manoj Karwa ◽  
Gaurav K. Jain ◽  
Rohit Dutt
Keyword(s):  
Human Plasma ◽  
Mobile Phase ◽  
Plasma Sample ◽  
Liquid Extraction ◽  
Liquid Liquid Extraction ◽  
Bioequivalence Testing ◽  
Development And Validation ◽  
Liquid Chromatographic ◽  
Positive Ion

A simple, sensitive, and selective ultra-performance liquid chromatographic (UPLC) method with mass spectrometric (UPLC-MS/MS) detection was developed for the determination of Rivaroxaban in human plasma sample. After a simple protein-precipitation by acetonitrile, the post-treatment samples were separated on a UPLC Bridged Ethyl Hybrid (BEH) C-18 column with 0.2% (v/v) formic acid in water: acetonitrile (60:40, v/v) as a mobile phase and analyzed in positive ion mode. The method developed was validated in human plasma with a daily working range of 2.02–997.72ng/mL with correlation coefficient, r2=0.999936. The method proved to be accurate (recovery, 97.0–107.95%), precise (2.21-7.21%), rapid (run time 2.5 min) and specific. In conclusion, the present validated method could be applied for pharmacokinetic study and bioequivalence testing of Rivaroxaban products.

scholarly journals Lipemia in the Plasma Sample Affects Fentanyl Measurements by Means of HPLC-MS2 after Liquid-Liquid Extraction

Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4514
Author(s):  
Marta Tikhomirov ◽  
Tomasz Śniegocki ◽  
Błażej Poźniak
Keyword(s):  
Forensic Toxicology ◽  
Liquid Extraction ◽  
Rabbit Plasma ◽  
Chromatography Method ◽  
Method Performance ◽  
Liquid Liquid Extraction ◽  
Normal Plasma ◽  
Validation Procedure ◽  
Liquid Chromatography Method ◽  
The Impact

Examination of fentanyl levels is frequently performed in certain scientific evaluations and forensic toxicology. It often involves the collection of very variable blood samples, including lipemic plasma or serum. To date, many works have reported the methods for fentanyl detection, but none of them have provided information about the impact on the assay performance caused by an excessive amount of lipids. This aspect may be, however, very important for highly lipophilic drugs like fentanyl. To address this issue, we developed the liquid chromatography method with mass spectrometry detection and utilized it to investigate the impact of lipids presence in rabbit plasma on the analytical method performance and validation. The validation procedure, conducted for normal plasma and lipemic plasma separately, resulted in good selectivity, sensitivity and linearity. The limits of detection and quantification were comparable between the two matrices, being slightly lower in normal plasma (0.005 and 0.015 µg/L) than in lipemic plasma (0.008 and 0.020 µg/L). Liquid–liquid extraction provided a low matrix effect regardless of the lipid levels in the samples (<10%), but pronounced differences were found in the recovery and accuracy. In the normal plasma, this parameter was stable and high (around 100%), but in the lipemic matrix, much more variable and less efficient results were obtained. Nevertheless, this difference had no impact on repeatability and reproducibility. In the present work, we provided reliable, convenient and sensitive method for fentanyl detection in the normal and lipemic rabbit plasma. However, construction of two separate validation curves was necessary to provide adequate results since the liquid-liquid extraction was utilized. Therefore, special attention should be paid during fentanyl quantification that involves lipemic plasma samples purified by this technique.

scholarly journals Homogeneous Liquid-Liquid Extraction Method for Selective Separation and Preconcentration of Trace Amounts of Palladium

2009 ◽  
Vol 6 (4) ◽  
pp. 1077-1084 ◽  
Author(s):  
Mohammad Reza Jamali ◽  
Yaghoub Assadi ◽  
Reyhaneh Rahnama Kozani ◽  
Farzaneh Shemirani
Keyword(s):  
Extraction Method ◽  
Limit Of Detection ◽  
Liquid Extraction ◽  
Selective Separation ◽  
Complexing Agent ◽  
Homogeneous Liquid ◽  
Liquid Liquid Extraction ◽  
Relative Standard ◽  
Separation And Preconcentration ◽  
Ternary Component System

A simple and effective homogeneous liquid-liquid extraction method for selective separation, preconcentration and spectrophotometric determination of palladium(II) ion was developed by using a ternary component system (water / tetrabutylammonium ion (TBA+) / chloroform). The phase separation phenomenon occurred by an ion–pair formation of TBA+and perchlorate ion. Thio-Michler’s ketone (TMK), 4, 4ˊ-bis (dimethylamino) thiobenzophenone, was used as a complexing agent. After optimization of complexation and extraction conditions ([TMK]=5.0x10-2mol L-1, [TBA+] = 2.0×10-2mol L-1, [CHCl3] = 60.0 µL, [ClO4-] = 2.5×10-2mol L-1and pH= 3.0), a preconcentration factor 10 was obtained for 10 mL of sample. The analytical curve was linear in the range of 2-100 ng mL-1and the limit of detection was 0.4 ng mL-1. The relative standard deviation was 3.2% (n=10). Accuracy and application of the method was estimated by using test samples of natural and synthetic water spiked with different amounts of palladium(II) ion. The method is very simple and inexpensive.

Determination of Tin in Canned Fruits and Vegetables by Atomic Absorption Spectrometry and Liquid–Liquid Extraction

1994 ◽  
Vol 77 (6) ◽  
pp. 1627-1630 ◽  
Author(s):  
Ana M Martín ◽  
Mercedes Sánchez ◽  
Pedro Espinosa ◽  
Gracia Bagur
Keyword(s):  
Aqueous Phase ◽  
Fruits And Vegetables ◽  
Methyl Ketone ◽  
Absorption Spectrometry ◽  
Liquid Extraction ◽  
Acid Complex ◽  
Liquid Liquid Extraction ◽  
Relative Standard ◽  
Good Agreement

Abstract A method was developed for the determination of tin based on the extraction of its 5,5-methylenedisalicylohydroxamic acid complex with 1.09M isobutyl methyl ketone in tributyl phosphate. After the samples were treated with nitric and hydrochloric acid, the aqueous phase was made to 0.05M in perchloric acid. When the ratio of aqueous phase to organic phase was 4:1 (v/v), the detection limit and the relative standard deviation (n = 7,50 μg tin) were 0.20 μg/mL and 0.9%, respectively. The proposed method was applied to the analysis of tin in canned fruits and vegetables. The results were in good agreement with those obtained by the phenylfluorone method.

scholarly journals COMPARISON OF THREE EXTRACTION METHODS OF ALLOPURINOL IN URIC ACID HERBAL MEDICINE WITH HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY QUANTIFICATION

2021 ◽  
pp. 141-147
Author(s):  
RIMADANI PRATIWI ◽  
RASPATI D. MULYANINGSIH ◽  
NYI M. SAPTARINI
Keyword(s):  
Herbal Medicine ◽  
High Performance ◽  
Solid Phase ◽  
Extraction Methods ◽  
Liquid Extraction ◽  
Filtering Method ◽  
Liquid Liquid Extraction ◽  
Accuracy And Precision ◽  
Relative Standard ◽  
Parameters Of Accuracy

Objective: This study was aimed to understand and determine the effectiveness of allopurinol extraction in herbal medicine from three extraction methods based on parameters of accuracy and precision. Methods: The study consisted of three methods including dissolving and filtering, liquid-liquid extraction, and solid-phase extraction with mixed-mode cation exchanger (SPE-MCX). The procedures were carried out using NaOH and HCl in dissolving and filtering method; methanol, HCl, and ethyl acetate in liquid-liquid extraction; and NH4OH elution solvent in SPE-MCX. Results: The results showed that extraction effectiveness based on accuracy level was the dissolving and filtering method>SPE-MCX>liquid-liquid extraction with % recovery+SD of 91.314+2.903%, 87.533+4.950%, and 54.549+3.517%, respectively. The precision level was the dissolution and filtering method>SPE-MCX>liquid-liquid extraction based on % relative standard deviations (RSD) of 3.18%, 5.226%, and 6.446%, respectively. Conclusion: It can be concluded that the allopurinol extraction method with the highest effectiveness based on accuracy and precision parameters in herbal medicine is the dissolving and filtering method.

scholarly journals Liquid-liquid extraction combined with high performance liquid chromatography-diode array-ultra-violet for simultaneous determination of antineoplastic drugs in plasma

2011 ◽  
Vol 47 (2) ◽  
pp. 363-371 ◽  
Author(s):  
Ananda Lima Sanson ◽  
Suéllen Cristina Rennó Silva ◽  
Matheus Coutinho Gonçalves Martins ◽  
Alexandre Giusti-Paiva ◽  
Patrícia Penido Maia ◽  
...  
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Liquid Extraction ◽  
Therapeutic Drug ◽  
Diode Array ◽  
Antineoplastic Drugs ◽  
Liquid Liquid Extraction ◽  
Relative Standard

A liquid-liquid extraction (LLE) combined with high-performance liquid chromatography-diode array detection method for simultaneous analysis of four chemically and structurally different antineoplastic drugs (cyclophosphamide, doxorubicin, 5-fluorouracil and ifosfamide) was developed. The assay was performed by isocratic elution, with a C18 column (5 µm, 250 x 4.6 mm) and mobile phase constituted by water pH 4.0- acetonitrile-methanol (68:19:13, v/v/v), which allowed satisfactory separation of the compounds of interest. LLE, with ethyl acetate, was used for sample clean-up with recoveries ranging from 60 to 98%. The linear ranges were from 0.5 to 100 µg mL-1, for doxorubicin and 1 to 100 µg mL-1, for the other compounds. The relative standard deviations ranged from 5.5 to 17.7%. This method is a fast and simple alternative that can be used, simultaneously, for the determination of the four drugs in plasma, with a range enabling quantification of the drugs in pharmacokinetics, bioequivalence and therapeutic drug-monitoring studies.

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