Principles of Micellar Electrokinetic Capillary Chromatography Applied in Pharmaceutical Analysis

Since its introduction capillary electrophoresis has shown great potential in areas where electrophoretic techniques have rarely been used before, including here the analysis of pharmaceutical substances. The large majority of pharmaceutical substances are neutral from electrophoretic point of view, consequently separations by the classic capillary zone electrophoresis; where separation is based on the differences between the own electrophoretic mobilities of the analytes; are hard to achieve. Micellar electrokinetic capillary chromatography, a hybrid method that combines chromatographic and electrophoretic separation principles, extends the applicability of capillary electrophoretic methods to neutral analytes. In micellar electrokinetic capillary chromatography, surfactants are added to the buffer solution in concentration above their critical micellar concentrations, consequently micelles are formed; micelles that undergo electrophoretic migration like any other charged particle. The separation is based on the differential partitioning of an analyte between the two-phase system: the mobile aqueous phase and micellar pseudostationary phase. The present paper aims to summarize the basic aspects regarding separation principles and practical applications of micellar electrokinetic capillary chromatography, with particular attention to those relevant in pharmaceutical analysis

CHIRAL SEPARATION OF CETIRIZINE ENANTIOMERS BY CYCLODEXTRIN MEDIATED CAPILLARY ELECTROPHORESIS

Chiral separation cetirizine, a second generation H1 antagonist was studied by cyclodextrine (CD) mediated capillary electrophoresis. The influence on the separation of several parameters including pH and concentration of the background electrolyte (BGE), CD type and concentration, applied voltage and temperature were studied and the electrophoretic and analytic parameters were optimized. The best conditions for the chiral separation were obtained using 25mM disodium hydrogeno-phosphate – 25mM sodium didydrogeno-phosphate (1:1) as BGE, 5mM sulfobuthyl ether- β-CD as chiral selector, a voltage of + 20kV, temperature of 20°C, injection pressure/time of 50mbar/ 1sec, UV detection at 230nm. The analytical performance of the method was evaluated. The proposed method was successfully applied to the enantioselective assay of cetirizine in pharmaceutical formula-tions. CE proved to be a rapid, specific, reliable and cost-effective method for the chiral separation of cetirizine enantiomers and can be useful for laboratories performing routine analysis.

Essential Guide of Analysis Methods Applied to Silver Complexes with Antibacterial Quinolones

To describe the chemical structure and characterize physico-chemical properties of organometallic complexes it is necessary to use a complex set of analysis methods. Thus, this review has been compiled as a relevant guide which includes the most commonly used methods of analysis in the study of silver complexes with antibacterial quinolones, compounds with promising biological potential. This selection of analysis methods puts on balance the obtained data and the accessibility of the experimental approach. The steps to follow in order to obtain reliable structural information about organometallic complexes of silver, particularly the silver complexes of antibacterial quinolones, are established and presented in the review

Basic principles for recommending and advising the use of cosmetics

UMF Tîrgu Mureş, Facultatea de Farmacie, Tîrgu Mureş, România, IP USMF „Nicolae Testemiţanu” din Republica MoldovaObiectivul studiului: Argumentarea necesităţii de elaborare şi publicare a unui compendiu care să ghideze farmacistul pentru realizarea consilierii profesioniste în activităţile de recomandare şi eliberare a produselor cosmetice. Iniţierea unei colaborări în acest sens între disciplinele de specialitate a Facultăţilor de Farmacie: din Tîrgu Mureş – România şi respectiv din Chişinău – Republica Moldova. Material şi metode: Studiu bibliografic. Rezultate: Atât în România cât şi în spaţiul Uniunii Europene, produsul cosmetic este delimitat legislativ de medicamente şi de alte produse pentru sănătate, fiind constituit din: „orice substanţă sau preparat care urmează să fie pus în contact cu diverse părţi externe ale corpului, cu scopul exclusiv sau principal de a le curăţa, a le parfuma, a le modifica aspectul, a le corecta mirosurile corporale, a le proteja ori a le menţine în bună stare”. Luând în considerare toate criteriile care le particularizează, legea referitoare la produsele cosmetice defineşte 20 de categorii. Având în vedere utilizarea unor categorii de cosmetice ca bunuri de larg consum, legislaţia europeană este în permanenţă armonizată cu tendinţele pieţei cosmeticelor, având ca obiective principale: asigurarea siguranţei consumatorilor, protecţia mediului şi înlocuirea studiilor pe animale cu metode in vitro. Eliberarea produselor cosmetice din farmacie implică cunoaşterea unor criterii fundamentale de diferenţiere şi de recomandare a acestora astfel încât să se realizeze şi o consiliere fundamentată pe principii ştiinţifice, nu numai intuitive. Astfel, în practica farmaceutică este necesară cunoaşterea şi aplicarea următoarelor criterii: a) Tipurile de produse cosmetice în funcţie de scopul utilizării (se diferenţiază: produse pentru igienă şi protecţie, produse de înfrumuseţare şi respectiv produse pentru îngrijire şi întreţienere); b)Regiunea corpului pe care se aplică produsele (se diferenţiază: produse pentru regiunea cutanată, produse pentru păr şi pielea capului, produse pentru unghii şi respectiv produse pentru mucoase); c) Particularităţile anatomo-fiziologice (se diferenţiază produse destinate pentru: femei, gravide, nou-născuţi, copii, bărbaţi); d) Starea regiunii corpului pe care urmează să fie aplicat produsul (se diferenţiază: produse de întreţinere – pentru regiuni cu activitate fiziologică normală şi produse reparatorii – pentru regiuni deteriorate sub acţiunea factorilor exogeni sau endogeni); e) Particularităţile tipului de ten (se diferenţiază: produse pentru ten normal, ten alipic, ten deshidratat, ten mixt, tenuri sensibile; tenurile cu particularităţi, cum sunt cele sensibile sau tenul îmbătrânit prematur, necesită produse cu efecte protective şi reparatorii); f) Selectarea formei produsului cosmetic în funcţie de tipul tenului, în corelaţie cu acţiunea excipienţilor asupra regiunii sistemului intertegumentar pe care se aplică, proprietăţile fizico-chimice ale ingredientelor active din produs şi nivelul de penetraţie necesar pentru exercitarea acţiunii (numărul ingredientelor care se asociază depinde atât de nivelul penetraţiei, cât şi de complexitatea efectelor dorite). Concluzii: Diferenţierea produselor cosmetice şi recomandarea acestora la eliberarea din farmacie necesită utilizarea unor cunoştinţe şi aplicarea unor principii bine argumentate ştiinţific. Numai în acest mod poate fi fundamentată consilierea realistă, la nivel profesional corespunzător aşteptărilor solicitanţilor şi utilizatorilor de produse cosmetice

The Development of Third-Generation Tetracycline Antibiotics and New Perspectives

The tetracycline antibiotic class has acquired new valuable members due to the optimisation of the chemical structure. The first modern tetracycline introduced into therapy was tigecycline, followed by omadacycline, eravacycline, and sarecycline (the third generation). Structural and physicochemical key elements which led to the discovery of modern tetracyclines are approached. Thus, several chemical subgroups are distinguished, such as glycylcyclines, aminomethylcyclines, and fluorocyclines, which have excellent development potential. The antibacterial spectrum comprises several resistant bacteria, including those resistant to old tetracyclines. Sarecycline, a narrow-spectrum tetracycline, is notable for being very effective against Cutinebacterium acnes. The mechanism of antibacterial action from the perspective of the new compound is approached. Several severe bacterial infections are treated with tigecycline, omadacycline, and eravacycline (with parenteral or oral formulations). In addition, sarecycline is very useful in treating acne vulgaris. Tetracyclines also have other non-antibiotic properties that require in-depth studies, such as the anti-inflammatory effect effect of sarecycline. The main side effects of modern tetracyclines are described in accordance with published clinical studies. Undoubtedly, this class of antibiotics continues to arouse the interest of researchers. As a result, new derivatives are developed and studied primarily for the antibiotic effect and other biological effects

Simultaneous Determination of Loratadine, Desloratadine and Cetirizine by Capillary Zone Electrophoresis

Purpose: The aim of the study was the development of a simple and rapid analytical procedure for the determination of the most frequently used antihistamine derivatives. Methods: A capillary zone electrophoretic method was developed for the simultaneous separation of loratadine, desloratadine and cetirizine. Efforts were focused primarly on the optimisation of the experimental parameters: buffer composition and concentration, buffer pH, applied voltage, temperature, injection pressure and time. Results: The optimised parameters for the separation were: 25 mM buffer electrolyte, buffer pH 2.5, voltage + 25 kV, temperature 25 °C, injection pressure 50 mbar, injection time 3 seconds, capillary 48 cm (effective length 40 cm) x 50 m, detection at 240 nm. Under these conditions, the analysis time was below 5 minutes, the order of migration being: desloratadine, cetirizine and loratadine. The developed method was validated in terms of linearity, limits of detection and quantification, intra- and inter-day precision, selectivity and robustness. Conclusion: Capillary zone electrophoresis proved to be a suitable method for the simulatneous determination of the three studied antihistamine derivatives