Engineering of a Mantis-Forelimb-Inspired Bioabsorbable Lens-like Ocular Therapeutic (BLOT) Device for Effective Bacterial Keratitis Treatment

Bacterial keratitis poses a significant global challenge due to rapid progression, antibiotic resistance, and corneal drug delivery difficulties. Facing the problems, we designed a mantis-forelimb-inspired bioabsorbable lens-like ocular therapeutic (BLOT) device with an oriented microneedle for treating bacterial keratitis. Microneedles arranged on the outer ring possess varying tilted angles, facilitating minimally invasive delivery of therapeutics to deeper corneal layers while reducing tissue damage. Additionally, sericin microspheres were engineered for in situ reduction of silver nanoparticles, which were then integrated in the oriented microneedles, demonstrating highly efficient antibacterial properties after penetrating the corneal epithelial layer. Notably, treatment with local BLOT produced a significantly thinner cornea (643.5 ± 5.3 μm) than levofloxacin eye drops (920.7 ± 5.7 μm) in a rabbit model of bacterial keratitis, demonstrating nearly 30% reduction in thickness. As a minimally invasive ocular drug delivery system, the BLOT device facilitates efficient and rapid corneal healing, offering a novel solution for bacterial keratitis treatment.