Optimizarea metodei HPLC pentru analiza fructelor de Armurariu (Silybum Marianum (L.) Gaertn)

Abstract

Optimization of the HPLC method for analysis of Milk-Thistle fruit (Silybum marianum (L.) Gaertn). An interlaboratory irreproducibility of the results of Milk-Thistle fruit assay has been discovered at realization of analytical procedure by the European Pharmacopoeia. It was found, that this irreproducibility is caused by insufficient plenitude of the analytes extraction from vegetal material. A new procedure of probe preparation, that consists of two sequential extractions by ethylic alcohol 40% for 60 min at 70°С, has been developed. The offered procedure ensures recovery about 98 % and essentially decreases the volume of work. Use of acetonitrile in the mobile phase composition and optimization of the gradient shape or switch-over to isocratic elution are offered for decrease of the analysis time. Key words: Silybum marianum, flavonolignans, HPLC-UV, pharmaceutical analysis.

La efectuarea analizei cantitative a fructelor de armurariu prin metoda Farmacopeei Europene s-a depistat o ireprodictibilitate interlaborator al rezultatelor. S-a stabilit că aceasta ireproductibilitate este condiţionată de insuficienţa plenitudinii de extracţie a analiţilor din produsul vegetal. S-a elaborat un nou procedeu de preparare a probelor, care constă din două extracţii consecutive cu alcool etilic 40% timp de 60 min la temperatura 70°C. Procedeul propus asigură regăsirea circa 98% şi micşorarea esenţială a volumului de lucru. Pentru reducerea timpului analizei cromatografice s-a propus utilizarea acetonitrilului în componenţa fazei mobile şi optimizarea formei gradientului sau trecerea la eluare izocratică.