Living cells do not interface naturally with nanoscale materials, although such artificial organisms can have unprecedented multifunctional properties, like wireless activation of enzyme function using electromagnetic stimuli. Realizing such interfacing in a nano-biohybrid organism (or nanorg) requires (1) chemical coupling via affinity binding and self-assembly, (2) the energetic coupling between optoelectronic states of artificial materials with the cellular process, and (3) the design of appropriate interfaces ensuring biocompatibility. Here we show that seven different coreshell quantum dots (QDs), with excitations ranging from ultraviolet to near-infrared energies, couple with targeted enzyme sites in bacteria. When illuminated by light, these QDs drive the renewable production of different biofuels and chemicals using carbon-dioxide (CO 2 ), water, and nitrogen (from air) as substrates. These QDs use their zinc-rich shell facets for affinity attachment to the proteins. Cysteine zwitterion ligands enable uptake through the cell, facilitating cell survival.Together, these nanorgs catalyze light-induced air-water-CO 2 reduction with a high turnover

The emergence of multidrug‐resistant (MDR) pathogens represents one of the most urgent global public health crises. Light‐activated quantum dots (QDs) are alternative antimicrobials, with efficient transport, low cost, and therapeutic efficacy, and they can act as antibiotic potentiators, with a mechanism of action orthogonal to small‐molecule drugs. Furthermore, light‐activation enhances control over the spatiotemporal release and dose of the therapeutic superoxide radicals from QDs. However, the limited deep‐tissue penetration of visible light needed for QD activation, and concern over trace heavy metals, have prevented further translation. Herein, we report two indium phosphide (InP) QDs that operate in the near‐infrared and deep‐red light window, enabling deeper tissue penetration. These heavy‐metal‐free QDs eliminate MDR pathogenic bacteria, while remaining non‐toxic to host human cells. This work provides a pathway for advancing QD nanotherapeutics to combat MDR superbugs.

Drug-resistant bacterial infections are a growing cause of illness and death globally. Current methods of treatment are not only proving less effective but also perpetuate evolution of new resistance. Here we propose, through an in vivo model, a new treatment for drug-resistant bacterial infection that uses semiconductor nanoparticles, called quantum dots (QDs), that can be activated by light to produce superoxide to specifically and effectively kill drug-resistant bacteria. We adapt this technology for in vivo assessment of toxicity and treatment of a subcutaneous infection in mice. As our cadmium telluride QDs with 2.4 eV band gap (CdTe-2.4 QDs) are activated by blue light, we engineered LED patches to adhere to the infection site on mice, thus providing the light necessary for the activity of injected QDs and treatment of the infection. We show, through assessment of body weight, histology, and inflammation and oxidative stress markers in serum, that the CdTe-2.4 QDs are nontoxic at concentrations that reduce drug-resistant bacterial viability in subcutaneous abscesses. Further, CdTe-2.4 QDs did not accumulate in the body and were safely excreted in urine via renal clearance. CdTe-2.4 QD treatment decreased abscess viability by as much as 7 orders of magnitude. We thus propose an alternative treatment approach for drug-resistant topical infections: the injection of a low concentration of QDs and the application of an adhesive patch comprising only an LED and a battery. This treatment could revolutionize last-resort treatments of burn wounds, cellulitis, and other skin infections.

The emergence of multidrug-resistant (MDR) pathogens represents one of the most urgent global public health crises.L ight-activated quantum dots (QDs) are alternative antimicrobials,w ith efficient transport, low cost, and therapeutic efficacy,and they can act as antibiotic potentiators, with am echanism of action orthogonal to small-molecule drugs.Furthermore,light-activation enhances control over the spatiotemporal release and dose of the therapeutic superoxide radicals from QDs.H owever,t he limited deep-tissue penetration of visible light needed for QD activation, and concern over trace heavy metals,have prevented further translation. Herein, we report two indium phosphide (InP) QDs that operate in the near-infrared and deep-red light window,e nabling deeper tissue penetration. These heavy-metal-free QDs eliminate MDR pathogenic bacteria, while remaining non-toxic to host human cells.This work provides apathway for advancing QD nanotherapeutics to combat MDR superbugs.

The increasing prevalence of drug-resistant bacterial strains is causing illness and death in an unprecedented number of people around the globe. Currently implemented small-molecule antibiotics are both increasingly less efficacious and perpetuating the evolution of resistance. Here, we propose a new treatment for drug-resistant bacterial infection in the form of indium phosphide quantum dots (InP QDs), semiconductor nanoparticles that are activated by light to produce superoxide. We show that the superoxide generated by InP QDs is able to effectively kill drug-resistant bacteria in vivo to reduce subcutaneous abscess infection in mice without being toxic to the animal. Our InP QDs are activated by near-infrared wavelengths with high transmission through skin and tissues and are composed of biocompatible materials. Body weight and organ tissue histology show that the QDs are nontoxic at a macroscale. Inflammation and oxidative stress markers in serum demonstrate that the InP QD treatment did not result in measurable effects on mouse health at concentrations that reduce drug-resistant bacterial viability in subcutaneous abscesses. The InP QD treatment decreased bacterial viability by over 3 orders of magnitude in subcutaneous abscesses formed in mice. These InP QDs thus provide a promising alternative to traditional small-molecule antibiotics, with the potential to be applied to a wide variety of infection types, including wound, respiratory, and urinary tract infections.