Understanding the intrinsic fluorescence of piperine in microheterogeneous media: partitioning and loading studies

Abstract

Piperine, an ingredient of black pepper, is widely used in pharmaceutical applications. This study explores the intrinsic fluorescence of piperine in different microheterogeneous media (i.e., dimyristoylphosphatidylcholine (DMPC) small unilamellar vesicles (SUVs), multilamellar vesicles (MLVs) and β-cyclodextrin (β-CD) and bile salts, namely, sodium cholate (NaC) and sodium deoxycholate (NaDC)). The partitioning of piperine into all the discussed organized media was confirmed through a UV-visible absorption study and fluorescence intensity study. Piperine fluorescence was sensitive towards the temperature-induced microenvironmental changes in both DMPC SUVs and MLVs. It disturbed DMPC MLVs at higher mol%, as confirmed from differential scanning calorimetry (DSC) and dynamic light scattering (DLS) techniques. The fluorescence intensity study confirmed the interior location of piperine in β-CD and bile salt micelles.