Development and validation of a fluorimetric method to determine quassin in polymeric nanocapsule suspension

A simple, rapid, and sensitive fluorimetric method was developed and validated to quantify quassia in polymeric nanocapsule suspensions and non polymeric suspensions, using acetonitrile as a solvent. The excitation and emission wavelengths were set at 397 nm and 465 nm, respectively. The calibration graph was linear from 0.05 to 0.25 µg/mL with a correlation coefficient of 0.9892. The detection and quantitation limits were 2.4 and 0.8 µg/mL, respectively. The validation results confirmed that the developed method is specific, linear, accurate, and precise for its intended use. The current method was successfully applied to the evaluation of curcumin content in lipid and polymeric nanocapsule suspensions during the early stage of formulation development.