Abstract
COS-CMC-PEGDA hydrogel was fabricated through bio-ink mixing at two different temperatures (4°C and 30°C) to investigate its drug release performance in the Gastric and Intestinal fluid conditions. The polyelectrolyte complex was transformed into hydrogel through UV crosslinking using Irgacure 2959 as the photoinitiator. Vancomycin Hydrochloride (COVAN) was loaded into the hydrogel solution by mixing it. Fourier transform Infrared Spectroscopy, Scanning Electron Microscopy, X-ray diffraction, Differential Scanning Calorimetry, and Thermogravimetric Analysis were done to characterize the two different hydrogels with and without the drug. The hydrogels exhibited pH and temperature-responsive swelling behavior. The Equilibrium Swelling Ratio for both the drug-free hydrogels was highest at 6.8 pH and 37℃, having a value of ~ 1000%, and the lowest being at 1.2 pH at a range of 450-650%. 4°(D)- drug-incorporated hydrogel mixed at 4℃ showed the highest release in intestinal fluid condition at 37℃ with around 98% of the total drug released after a day. 4°(D) showed higher drug release in a sustained manner at 1.2 pH, 37℃ but lower drug release at 1.2 pH, 30℃ compared to N(D) (drug incorporated regular hydrogel mixed at 30°C). The drug release data fit into the Korsmeyer-Peppas Model, where the n value indicated a Fickian drug transport in most cases. 4°(D) showed higher drug release and higher drug incorporation compared to N(D) at most conditions. Therefore, altering the temperature of mixing of the hydrogel solution has the potential to improve the Drug Delivery Systems and achieve better therapeutic value. In this case, 4°(D) has potentially greater efficacy compared to N(D) for targeted colonic drug delivery.