Abstract
Traditional antibiotics (such as levofloxacin) are mainly administered orally or via injection. However, these delivery methods struggle to maintain an optimal drug concentration, leading to low bioavailability and potential toxic side effects. Therefore, this study proposes a controlled-release antibiotic delivery system to achieve on-demand drug administration. Specifically, the system utilizes the hydrophobic cavities of PAMAM to efficiently load antibiotics and modifies its surface with hydrophilic BSA via coupling to enhance nanodrug stability during systemic circulation. BSA is conjugated to PAMAM using an N-hydroxysuccinimide active ester containing disulfide bonds, enabling drug release through disulfide bond cleavage in response to glutathione (GSH). Characterization techniques, including nuclear magnetic resonance, Fourier transform infrared spectroscopy, dynamic light scattering, contact angle measurement, and thermogravimetric analysis, confirmed the successful construction of the nanodrug. In vitro drug release experiments demonstrated the nanodrug's responsiveness to GSH. Additionally, antibacterial assays showed that the BSA@PAMAM nanodrug loaded with levofloxacin exhibited enhanced antibacterial effects in a GSH environment, indicating that this system can effectively regulate antibiotic release, optimize drug administration, improve therapeutic efficacy, and reduce adverse effects.