Alginate/carboxymethylcellulose-based hydrogels as pH-sensitive drug delivery systems: facile production with enhanced degradation, thermal and mechanical properties

pH-Sensitive alginate (ALG)/sodium carboxymethylcellulose (CMC) hydrogels were synthesized using a novel technique to utilize as a drug carrier in this study. The characterization of hydrogels was performed using FTIR (Fourier-transformed infrared spectroscopy), SEM(scanning electron microscopy), TGA (thermogravimetric analysis), DSC (differential scanning calorimetry), gel content and mechanical tests. The last technique is new and it is compared with the most well-known ionic crosslinking method to investigate the effectiveness of the technique. Gel content, degradation and thermal and mechanical stabilities were found to be higher. Swelling and degradation behaviors of hydrogels were studied in simulating gastric juice of pH 1.2 or simulating intestinal fluid of pH 6.8 and simulating colon fluid of pH 7.4 at 37 ?. The maximum swelling degree was observed at pH 7.4, and the minimum swelling degree was obtained at pH 1.2. An Anti-arrhythmics drug, propranolol hydrochloride (PPN), was loaded onto the obtained hydrogels as a model drug. Encapsulation efficiency (%) and drug loading amount (g/g) of ALG/CMC hydrogels synthesized by a new technique were found to be 61-68.4% and 0.152-0.171 g/g, respectively. The values of initial burst release at 15 min (%), drug released at 7 h (%) and equilibrium drug release were researched. Different kinetic model parameters (zero-order, first-order, Higuchi, and Korsmeyer-Peppas models) were calculated to investigate the drug release mechanism. The engineered hydrogels displayed controlled swelling capacity, cavitary surfaces, more porosity, high degradation resistance, gel content, thermal and mechanical properties and controlled drug release. These findings suggest that hydrogels synthesized by this new technique may be useful as a drug delivery system.