Katarzyna Madej

Review of Analytical Methods for Identification and Determination of PHEs and Tricyclic Antidepressants

A critical review of analytical methods for identification and determination of some phenothiazine derivatives and tricyclic antidepressants in a variety of materials is presented. The methods have been divided into five groups accordingly to the applied analytical techniques: spectrometric, chromatographic, immunoassay, electrochemical, and capillary electrophoretic. The review is based on a survey of chemical and toxicological literature covering the articles mainly from 2000 until now. A brief description of physicochemical properties of the compounds of interest has been also presented.

Sequential cloud-point extraction for toxicological screening analysis of medicaments in human plasma by high pressure liquid chromatography with diode array detector

A complex extraction system with the use of cloud-point extraction technique (CPE) was developed for sequential isolation of basic and acidic/neutral medicaments from human plasma/serum, screened by HPLC/DAD method. Eight model drugs (paracetamol, promazine, chlorpromazine, amitriptyline, salicyclic acid, opipramol, alprazolam and carbamazepine) were chosen for the study of optimal CPE conditions. The CPE technique consists in partition of an aqueous sample with addition of a surfactant into two phases: micelle-rich phase with the isolated compounds and water phase containing a surfactant below the critical micellar concentration, mainly under influence of temperature change. The proposed extraction system consists of two chief steps: isolation of basic compounds (from pH 12) and then isolation of acidic/neutral compounds (from pH 6) using surfactant Triton X-114 as the extraction medium. Extraction recovery varied from 25.2 to 107.9% with intra-day and inter-day precision (RSD %) ranged 0.88-1087 and 5.32-17.96, respectively. The limits of detection for the studied medicaments at λ 254nm corresponded to therapeutic or low toxic plasma concentration levels. Usefulness of the proposed CPE-HPLC/DAD method for toxicological drug screening was tested via its application to analysis of two serum samples taken from patients suspected of drug overdosing.

Analytical methodologies for the determination of benzodiazepines in biological samples.

Benzodiazepine drugs belong to important and most widely used medicaments. They demonstrate such therapeutic properties as anxiolytic, sedative, somnifacient, anticonvulsant, diastolic and muscle relaxant effects. However, despite the fact that benzodiazepines possess high therapeutic index and are considered to be relatively safe, their use can be dangerous when: (1) co-administered with alcohol, (2) co-administered with other medicaments like sedatives, antidepressants, neuroleptics or morphine like substances, (3) driving under their influence, (4) using benzodiazepines non-therapeutically as drugs of abuse or in drug-facilitated crimes. For these reasons benzodiazepines are still studied and determined in a variety of biological materials. In this article, sample preparation techniques which have been applied in analysis of benzodiazepine drugs in biological samples have been reviewed and presented. The next part of the article is focused on a review of analytical methods which have been employed for pharmacological, toxicological or forensic study of this group of drugs in the biological matrices. The review was preceded by a description of the physicochemical properties of the selected benzodiazepines and two, very often coexisting in the same analyzed samples, sedative-hypnotic drugs.

HPLC/DAD Screening Method for Selected Psychotropic Drugs in Blood

The influence of experimental conditions on gradient high-performance liquid chromatography/diode array detector separation and identification of 13 psychotropic drugs belonging to two groups--phenothiazines and tricyclic antidepressants--was examined. The main interaction effects of three experimental factors were determined according to a 2 3 factorial design, and the optimum conditions of analysis were searched for. The degree to which the chromatographic peaks overlap is taken into account in a proposed criterion for separation quality. The screening analysis proposed was tested on whole blood samples spiked with mixtures of the examined drugs. The method was characterized by such validation parameters as relative retention times, absorbance ratios at two wavelengths, detection limits, linearity ranges, and extraction recoveries. The method proved to be a suitable tool for the identification of psychotropic drugs tested for forensic purposes.

Optimum TLC system for identification of phenothiazines and tri- and tetracyclic antidepressants

The TLC separation of twelve drugs from three pharmaceutical groups: phenothiazines and tri and tetracyclic antidepressants is presented. Three kinds of eluents and two types of solid phases (RP 18 and Silica gel 60) were used. The composition of mobile phases was optimized by the Simplex method. In the basic optimization criterion the differences betweenRf values of the spots corresponding to individual drugs were taken into account. An auxiliary criterion was based on the colour of the spots, which were developed with appropriate reagents. The experimental data obtained during optimization were interpreted using a matrix presentation. In the optimal conditions the differences between positions of the spots enable identification of ten of the examined drugs, but two remained unresolved.

Study of SPE Conditions for CE Determination of Tricyclic Antidepressants in Body Fluids

Abstract The optimal solid‐phase extraction conditions for six tricyclic antidepressants present in body fluids have been studied. The compounds were separated and detected by capillary electrophoresis with UV spectrophotometry. In the examinations, three sorbents, five pretreatments of body fluids, and four extraction procedures were taken into account. On the basis of preliminary experiments, the best starting conditions were chosen for further optimization of such factors as sorbent mass and volumes of conditioning, washing, and eluent reagents. In the optimized conditions, the average extraction recoveries and their repeatability for all drugs present in whole blood and serum have been evaluated.

Drug screening in human plasma by cloud-point extraction and HPLC

Cloud-point extraction (CPE) with RP-HPLC/DAD detection was used to develop a screen for six model basic drugs (paracetamol, promazine, amitriptyline, nortriptyline, clomipramine and chlorpromazine) in human plasma. These drugs’ varied hydrophobicities entail different affinities for the micelle-rich phase and CPE extraction efficiencies. Extraction recovery (except paracetamol) was above 80% and reproducibility (RSD%) ranged from 2.88 to 10.26 intraday and from 3.12 to 12.33 interday. The limits of detection were: 0.125 µg mL−1 (promazine and chlorpromazine), 0.25 µg mL−1 (amitriptyline and nortriptyline) and 0.5 µg mL−1 (paracetamol and clomipramine). The method was linear over the ranges: 0.125–1.0 µg mL−1 (promazine and chlorpromazine), 0.25–1.0 µg mL−1 (amitriptyline and nortriptyline), 0.5–1.0 µg mL−1 (clomipramine) and 0.5–10 µg mL−1 (paracetamol). The procedure is a good alternative to the SPE or LLE sample preparation usually used.

Study of Separation and Extraction Conditions for Five Neuroleptic Drugs by an LLE-HPLC-DAD Method in Human Plasma

Abstract Separation and extraction conditions for four atypical neuroleptics (clozapine, N-desmethylclozapine (active metabolite of clozapine), olanzapine, and quetiapine) and one classical neuroleptic (perazine) in human plasma have been studied. Reverse phase chromatography (RP-18) with the mobile phase consisted of: A. aq. orthophosphoric acid with addition of N,N,N′,N′-tetramethylethylendiamine (TEMED), pH = 5.0, and B. acetonitrile, in gradient flow, was selected. As the optimal liquid-liquid extraction conditions, sample pH = 11.6, extraction system, ethyl acetate/n-hexane/isopropanol (16:3:1, v/v/v), and back extraction into 0.01% orthophosphoric acid were chosen.

Cloud-point extraction followed by high pressure liquid chromatography with UV spectrophotometric detection for determination of permethrin in urine samples

A new, effective cloud-point extraction (CPE) method for determination of the pesticide, permethrin, from the pyrethroid group, in human urine, by high-pressure liquid chromatography with UV spectrophotometric detection, was developed and validated. The key extraction conditions were as follows: surfactant 5% (w/v) Triton X-114, temperature and incubation time of 40 °C and 30 min, respectively, and 100 μL organic solvent (acetonitrile) for dissolving the micellar phase. The acetonitrile micellar phase with the isolated permethrin was analyzed by reverse-phase high-pressure liquid chromatography using the gradient flow of a mobile phase consisting of water and acetonitrile. The main analytical parameters of the developed method were mean extraction recovery (89.9%), intra- (7.1, 9.1 and 13.6% RSD for 0.25, 0.5 and 1.0 μg mL−1 concentrations of permethrin, respectively) and interday (6.1, 10.3 and 14.1% RSD for 0.25, 0.5 and 1.0 μg mL−1 concentrations of permethrin, respectively) repeatability, limit of detection (0.025 μg mL−1) and limit of quantification (0.075 μg mL−1), as well as the linear range (0.075–2.000 μg mL−1, r2 = 0.9975). The evaluated parameters have enabled the proposed method to be hopefully useful for the monitoring of permethrin in urine samples taken from individuals exposed to this pesticide.

Determination of Fe(II)-Fe(III) and Fe(III)-Ni(II) by the two-component potentiometric complexometric titration

SummaryThe two-component complexometric potentiometric titration has been applied to the simultaneous determination of Fe(III) and Fe(II), and of Fe(III) and Ni(II) in solution. In each case the two analytes were determined by reading the end-points directly from the titration curve. The end-points are determined in a sense arbitrarily, but they are repeatable and easy to be detected precisely. However, the apparent (found) analytical results are biased. They are effectively corrected with the use of a set of two calibration equations (uncomplete second degree polynomials), which approximate the relationship between found endpoints and true concentrations of analytes in solution. The regression coefficients in the equations are determined on the basis of titration data obtained for standard solutions whose compositions correspond to a 22 factorial.