In current study, novel in situ formed
injectable self-assembled thermoreversible depot
gels based on N-(Vinylcaprolactam) were synthesized with a
carbohydrate polymer i.e.
sodium alginate in aqueous
solution using cold method. The prepared
gels preparations were intended to be utilized as
5-FU delivery depot after
injectable administration through subcutaneous route. The structural characterization of self-assembled
gels samples were studied through FTIR. The thermal properties of newly formed
gels complexes were investigated by DSC and TGA. While the morphology of
gels were assessed through SEM. The tunable gelation temperatures and phase transition of optimized formulations were confirmed by tube inverting, rheology determination and optical transmittance test. Thermo and pH response was evaluated at different temperatures and in various acidic and basic
buffer solutions. In vitro release experiments were conducted using Franz diffusion system to monitor the controlled delivery fashion of
gels matrices. Results concluded that depot
gels exhibit controlled delivery fashion with maximum release at pH 7.4 and 37 ± 2 °C. The biocompatible nature of blank
gels samples was assessed by MTT assay against Vero cell lines and was found safe. While killing ability of
5-FU encapsulated
gels was evaluated against HeLa (19 ± 0.22 μg/ml; 23 ± 0.55 μg/ml) and MCF-7 (21 ± 0.06 μg/ml and 22 ± 0.34 μg/ml)
cancer cell lines and were found effective to kill
cancer cells. Histopathological study showed that
gels depot is safe with no harmful effects on major organs. The in vivo bioavailability in rabbits showed controlled release (Cmax, 4465.78 ± 1.99 ng/ml) in comparison to free drug (Cmax, 4883.73 ± 3.32 ng/ml) administration after
subcutaneous injection.