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Diabetic foot ulcer (DFU) is becoming more serious concern as it affects 95% of diabetic patients worldwide. It has been shown that the Staphylococcus aureus and other Gram-negative microorganisms are the main reasons behind this disease. Though many antibiotics are presently used to treat the DFU, due to increased bacterial resistance, new alternative therapies are always welcome. To address this alarming issue, we have designed and synthesized the high-valence silver propamidine (Ag(II)PRO) complex as well as nanoparticles and characterized both by usual spectroscopic methods. The reverse microemulsion technique has been applied to synthesize Ag(II)PRO nanoparticles and its antibacterial activity has been compared with zero-valence silver nanoparticles (AgNPs) with similar size. The antibacterial efficacies of Ag(II)PRO nanoparticles and AgNPs were tested against Gram-negative and Gram -positive organisms responsible for DFU. The newly synthesized high-valence Ag(II)PRO nanoparticles showed higher antibacterial activity compared to silver-only nanoparticles (AgNPs). This study concludes that the high-valence Ag(II)PRO nanoparticles show better antibacterial activity than AgNPs and they may serve as the next generation therapeutic agent for the diabetic wound care. [ABSTRACT FROM AUTHOR]

Even with the prevalence of wounds, the medical technology for efficiently managing skin damage is still primitive. The disruption of any of the numerous healing processes can lead to problems in the time-sensitive healing actions of the dermal and epidermal layers. Bacterial infection is one of the major obstacles to proper wound healing as it poses a danger of causing long-term negative effects. Keeping the wound free of bacteria is imperative to the proper and hasty repair of dermal wounds. Silver has been widely used to treat wounds for its bactericidal properties. Although the mechanism of silver's antibacterial action is not fully understood, it exhibits a significant antimicrobial efficacy against a wide spectrum of bacterial species. A number of different approaches to the mechanism are reported and presented in this review. Silver nanoparticles (AgNPs) have been reported to exhibit enhanced antibacterial activity due to their increased surface-area-to-volume ratio. AgNPs are capable of various modifications, significantly broadening the therapeutic properties of the material as a result. This review explores the different aspects of silver and silver nanoparticles, and their antibacterial properties, which can be applied in the field of wound treatments. [ABSTRACT FROM AUTHOR]

Silver sulfide quantum dots (Ag2S QDs) as a theragnostic agent have received much attention because they provide excellent optical and chemical properties to facilitate diagnosis and therapy simultaneously. Ag2S QDs possess brightness and photostability suitable for intense and stable bioimaging. It has been verified via in vitro and in vivo studies that Ag2S QDs do not cause serious toxicity, unlike the first generation of widely used heavy metal-based (cadmium or lead) QDs. In particular, Ag2S QDs emit in the near infrared-II region (NIR-II window) that enables deep tissue penetration and imaging. Furthermore, various chemotherapeutic agents and targeting moieties can be efficiently conjugated to the surface of Ag2S QDs due to advanced technologies in the relevant surface chemistry using covalent bonding, high affinity, and electrostatic interaction. In addition, Ag2S QDs themselves exhibit an anticancer activity based on the photothermal effect. Consequently, Ag2S QDs can function as both a therapeutic agent and an imaging agent in imaging-based diagnosis concurrently, which led to the creation of Ag2S theragnostic nanomaterials. In this review, the synthetic methods, physicochemical properties, bioconjugations, and bioapplications of Ag2S QD theragnostic nanomaterials are discussed in detail.