Optimized-dose lidocaine-loaded sulfobutyl ether β-cyclodextrin/hyaluronic acid hydrogels to improve physical, chemical, and pharmacological evaluation for local anesthetics and drug delivery systems

Local anesthetics (LAs) are a class of drugs, which have wide applications in the treatment of post-operative pain care management. Long-acting LAs that can be given as a single dose analgesic are desperately needed. The prepared sulfobutylether β-cyclodextrin (SCD)/hyaluronic acid (HA) hydrogels were characterized by Fourier transform infrared and X-ray diffraction patterns. The as-prepared SCD/HA hydrogels greatly enhanced their swelling behavior and in vitro degradation properties. Furthermore, a scanning electron microscope reported that the surface morphology of the Lidocaine (LDC)-loaded SCD/HA hydrogels was smooth, and a significant change in porosity was observed after the addition of LDC (0.5%, 1.0%, and 1.5% w/v). The occurrence of cross-linking between the LDC and SCD/HA hydrogels was studied through rheological analysis. Approximately 94% of lidocaine (LDC) was released from the SCD/HA-LDC formulations by 24 h. The cytotoxicity of SCD/HA-LDC was studied against fibroblast (3T3) cells. SCD/HA-LDC showed a prolonged in vitro release and lower cytotoxicity when compared to free LDC. Furthermore, in vivo evaluation of the anesthetic properties in animal models showed that the SCD/HA-LDC showed a significantly prolonged analgesic effect when compared to free LDC. Moreover, the SCD/HA-LDC exhibited good biodegradability and biocompatibility in histological analyses. Overall, the findings suggest that the LDC-loaded SCD/HA hydrogels had a synergistic impact in prolonging analgesia without generating toxicity, and hence might be used as a long-acting analgesia therapeutic care. Graphical abstract: [Figure not available: see fulltext.] © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.