Executive Summary : | Antibiotic resistance is a significant threat to the pharmaceutical industry, with bacteria gaining resistance faster than the development of new antibiotics. Most antibiotics used today were discovered during the golden era of antibiotic development, but the rapid rise of drug-resistant strains and slow development of new antibiotics necessitate controlled activation of existing antibiotics. Photopharmacology offers target-specific light-controlled activation of drug molecules to enhance pharmacological efficiency and reduce off-target toxicity. However, poor penetration and enhanced cytotoxicity due to prolonged exposure to UV light limit applications. To address this issue, researchers are investigating the use of lanthanide-doped upconversion nanoparticles (UCNPs) as a tool for controlled release of antibiotics upon near-infrared light irradiation. UCNPs absorb two or more photons via long-lived intermediate states and emit radiation at a shorter wavelength. This approach allows for targeted activation with high spatio-temporal precision, overcoming the challenges of direct UV light irradiation. The main reason bacteria gain resistance is continuous exposure to active antibiotics. The researchers are trying to convert active antibiotics to an inactive form by installing a phtocaging group and functionalizing the UCNP with modified antibiotics with a photocleavable linker. Upon exposure to NIR light, the UCNPs emit UV light, cleaving the photocleavable linker and releasing the active antibiotics. This proposal aims to achieve near-infrared controlled release of commonly used antibiotics like trimethoprim, ciprofloxacin, and norfloxacin as a promising therapeutic strategy. |