Injectable alginate/collagen clindamycin hydrogel for treatment of surgical site infections

The current standard treatment for surgical site infections (SSIs) is marked by prolonged courses of antibiotics, which have limitations due to antibiotic resistance, systemic side effects, and poor patient adherence. We developed a novel injectable alginate/collagen clindamycin hydrogel that rapidly solidifies upon injection and allows for initial burst release followed by sustained release to maintain therapeutic levels. The rheological, morphological, and in-vitro release kinetics of the hydrogel were characterized. Furthermore, with an in-vivo murine SSI model incubated with logarithmic growth phase 1 x 105 CFU Staphylococcus aureus, one time treatment with injectable hydrogel containing 8 mg clindamycin successfully treated SSI comparable to a cumulative systemic antibiotic dose of 42 mg clindamycin. In an implant SSI model, two-time treatment with the injectable clindamycin antibiotic (16 mg total) successfully suppressed infection and prevented recalcitrant infection. To date, no group has developed a clindamycin encapsulated injectable alginate/collagen hydrogel for the treatment of infection. This tunable hydrogel may serve as an effective delivery vehicle for clinical applications in treating SSIs compared to conventionally available treatments.