Recent advances in endogenous and exogenous stimuli-responsive nanoplatforms for bacterial infection treatment

As drug-resistant bacterial infections escalate and antimicrobial resources become insufficient, new alternative therapies are critical. The emergence of nano drug delivery system, in addition to giving drugs sustained, targeted or longer half-life characteristics, also plays an important role in improving the therapeutic effect and reducing the toxic side effects of conventional drugs. Despite its potential benefits, the traditional nanomedical drug delivery system has some practical limitations, including incomplete and slow drug release, as well as insufficient accumulation at infection sites. Stimuli responsive nanoplatforms are hence developed to overcome the disadvantages of conventional nanoparticles, which can provide several advantages like: enhancing the pharmacokinetics and biodistribution of antimicrobial drugs, increasing their effective bioavailability, reducing their dosage frequency, and improving their antimicrobial efficacy against biofilm-related infections, while slowing down the development of antimicrobial resistance, which is expected to trigger a medical revolution in the field of human health, thus bringing huge clinical benefits. In this review, we provide an extensive review of the recent progress of endogenous and exogenous stimuli-responsive nanoplatforms in the antibacterial area. Using specific infectious microenvironments (pH, enzymes, reactive oxygen species and toxins), this review systematically presents the design principles of nano delivery systems and the mechanisms by which endogenous stimuli induce changes in the morphology or properties of delivery systems to achieve programmed drug release. Furthermore, exogenous stimuli such as light, heat, and magnetic fields can also control the release of drugs. Last but not least, we discussed the challenges and opportunities for future clinical translation of stimuli-responsive nanoplatforms in bacterial infections.