Production of Hydrogel Microneedles from Fish Scale Biopolymer

Abstract

This work presents for the first time, a scalable, low cost method for producing hydrogel microneedles from fish scales derived biopolymer using a modified low temperature press method. The microneedles are made from cross-linked hydrolyzed collagen (HC). The suitability of the microneedles for drug loading were tested by loading with Ferrous gluconate. Force analysis carried out in compression mode showed that the microneedles could withstand up to 0.136 N per microneedle before fracture which is sufficient strength to pierce the skin. The cross-linked microneedles swelled to 340% of their original mass in PBS and within 24 h released 34.5% of the loaded drug, while the non cross-linked microneedles dissolved within minutes. Chemical testing of the released drug confirmed that the drug released retained its chemical structure by forming colored complex with acetylsalicylic acid and UV spectrometry was used to quantify the concentration released. FTIR analysis confirmed the modified structure of the polymer when cross-linked. This proposed method allows cross-linking at room temperature using a thermal press method which can be easily scaled up.