Basil (Ocimum basilicum L.) seeds engender a smart material for intelligent drug delivery: On-Off switching and real-time swelling, in vivo transit detection, and mechanistic studies

Abstract

Hydrogels isolated from seeds of many plants are exploring extensively for biomedical applications. In this study, the compressed form of Ocimum basilicum L. hydrogel (OBH) was assessed for stimuli-responsive swelling behavior and sustained drug release potential. The swelling capacity of OBH tablets with and without drugs was appraised in deionized water (DW), saline solutions, and buffers of pH 1.2, 6.8, and 7.4. Stimuli-responsive swelling/deswelling behavior of tablets was evaluated in DW and normal saline, DW and ethanol, and at pH 7.4 and 1.2. Drug release study was evaluated at different pH similar to the gastrointestinal tract (GIT) and real-time in vivo transit of tablet was observed through X-ray. Scanning electron microscopy (SEM) analysis of tablets before and after swelling was also performed. The tablets exhibited noticeable swelling in all media except acidic buffer (pH 1.2). The tablets displayed swelling/deswelling attributes when placed alternately in different media. Release of theophylline (TF) and domperidone (DD) were sustained as the concentration of OBH increased ensuing zero-order kinetics and super case transport II mechanism. Highly porous texture with micro-channels was observed in the SEM analysis. X-ray images revealed the presence of a tablet in GIT even after 7 h. The study supported the use of OBH as a smart biomaterial for targeted and sustained release of drugs.