Controlled Release of 5‐Fluorouracil from Alginate Hydrogels by Cold HMDSO−Plasma Surface Engineering

For decades, 5‐fluorouracil (5FU) has been the only chemotherapeutic agent to demonstrate a strong activity against colorectal cancer. However intravenous administration of 5FU mandates the development of an oral controlled delivery system for improved patient compliances. With this rationale, hydrogels comprising polyvinyl alcohol and sodium alginate were crafted and subjected to cold atmospheric plasma treatment by coating with hexamethyldisiloxane (HMDSO) using three different carrier gases viz Ar, He and N2. Surface hydrophobicity ensuing from HMDSO plasma was evident from contact angle goniometry. FT‐IR analyses were affirmative of the effectual deposition of Si−O−Si and Si−CH3 groups on the hydrogel surfaces. Moreover, plasma treatment rendered the hydrogels stiffer and tougher. The plasma‐modified hydrogels displayed lower water uptake capacity in comparison to the pristine one. Drug release was significantly prolonged from the plasma‐treated hydrogels that conformed to the oral delivery of 5FU to colon. Preliminary kinetics assay revealed drug release was predominantly governed by polymer chain relaxation process post‐plasma modification. The Ar/HMDSO‐plasma modified hydrogel was found to be best of the lot for achieving an oral controlled release for 5FU. Cold hexamethyldisiloxane (HMDSO) plasma modification of polyvinyl alcohol/ alginate hydrogels rendered a hydrophobic surface with reduced wettability, rough topography, lower water uptake capacity and compact morphology. A controlled release profile for 5‐Fluorouracil (5FU) to the colon was confirmed from the HMDSO‐plasma coated hydrogels. Preliminary drug release kinetics assay revealed the predominance of polymer chain relaxational process on the drug release mechanism from HMDSO plasma‐treated hydrogels.