Abstract

DETERMINATION OF SN-38 CONTENTS IN NANOCAPSULES BY CHROMATOGRAPHIC AND SPECTROPHOTOMETRIC METHODS

Shilpi Prasad* and J. S. Dangi

Abstract

A rapid and sensitive reversed phase high performance liquid chromatography (RP-HPLC) method using isocratic elution with UV detection and UV spectrophotometric method was developed for quantification of SN-38 (7-ethyl-10-hydroxycamptothecin), a camptothecin derivative in a poly (lactic-co-glycolic acid) (PLGA) based nanocapsule (PLNP). Chromatographic separation was performed on a Kromasil,KR100,C18, (4.6 mm X 250 mm, 5μm) analytical column with a mobile phase containing a mixture of octane- 1-sulfonic acid sodium salt, potassium di hydrogen phosphate and acetonitrile (29:29:42v/v/v). SN-38 was detected at a wavelength of 265nm. The limit of detection (LOD) and limit of quantitation (LOQ) of HPLC method were found to be 0.006 μg mL-1 and 0.02 μg mL-1 for carboxylate and 0.002 μg mL-1 and 0.02 μg mL-1 for lactone form respectively. For UV method LOD and LOQ is 0.026 μg mL-1 and 0.08 μg mL-1 respectively. The methods were validated for linearity, accuracy, precision and robustness as per International Conference on Harmonization (ICH) guidelines and applied for determination of entrapment efficiency and drug loading in nanocapsules during in vitro analysis. Although HPLC method is more specific and precise and has better detection and quantification limits than UV method but quantitative determination by UV method becomes important when solvent recovery, cost effectiveness and time of analysis is important.

Keywords: HPLC, UV spectroscopy, Nanocapsules, 7-ethyl-10-hydroxycamptothecin, poly (lactic-co-glycolic acid).