Synthetic Antibacterial Quaternary Phosphorus Salts Promote Methicillin-Resistant Staphylococcus aureus-Infected Wound Healing.

Background: Drug-resistant microbes pose a global health concern, requiring the urgent development of effective antibacterial agents and strategies in clinical practice. Therefore, there is an urgent need to explore novel antibacterial materials to effectively eliminate bacteria. The synthesis of quaternary phosphonium salt in haloargentate systems, wherein the phosphorus atom is represented in a cationic form, is a possible strategy for the development of antibacterial materials. Methods: Using (triphenyl)phosphonium-based quaternary phosphorus salts with different spacer lengths (n=2, 4, 6) as a template, we designed three kinds of quaternary phosphorus salts as effective antibacterial agents against drug-resistant bacteria. Results: The synthesized quaternary phosphorus salt of (1,4-DBTPP)Br2 effectively prevented the formation of the bacterial biofilms, and degraded bacterial membranes and cell walls by promoting the production of reactive oxygen species, which exhibited effective therapeutic effects in a rat model of a superficial wound infected with methicillin-resistant Staphylococcus aureus. Conclusion: The quaternary phosphorus salt (1,4-DBTPP)Br2 demonstrated hemocompatibility and low toxicity, revealing its potential in the treatment of clinical infections.

Multifunctional Quaternary Phosphorus/Bromoargentate Hybrids: The Achievement of Greenish Blue Luminescence, Repeatable Photocurrent Responses and Durable Antimicrobial Activities with Enhanced Water Stability.

BACKGROUND: The realization of multifunction in one bulk material is fascinating for developing a new generation of devices. Quaternary phosphorus salts were seldom utilized as templates in haloargentate systems, and the hybridization of alkyl(triphenyl)phosphonium with halometallate will be a good strategy for the development of multifunctional material, especially for biological material. METHODS: Under the template of (triphenyl)phosphonium-based quaternary phosphorus salts with different spacer lengths (n=2, 3, 4), three bromoargentate hybrids were constructed via the solution method, ie, (1,2-DBTPP)(Ag2Br4) (1), {(1,3-DBTPP)2(Ag7Br11)]∙CH3CN∙H2O} n (2), and {[(1,4-DBTPP)(Ag5Br7)](CH3CN)2∙H2O} n (3) (1,2-DBTPP2+=ethane-1,2-diylbis (triphenyl)phosphonium, 1,3-DBTPP2+=propane-1,3-diylbis (triphenyl)phosphonium, 1,4-DBTPP2+=butane-1,4-diylbis (triphenyl)phosphonium)). RESULTS: The (Ag7Br11) n 4n- chain in 2 is a new type of 1-D bromoargentate chain constructed from cubane-like Ag4Br4 nodes, AgBr4 tetrahedrons and AgBr3 triangles. Interestingly, by elongating spacer n from 2 to 4, argentophilicity interactions are weakened, and the hydrogen bonds are strengthened. Consequently, their water stabilities and photocurrents are improved, in which the Ag-4d/Br-4p to π* anti-bonding orbital of the quaternary phosphorus transfer is facilitated. Furthermore, the greenish blue emissions can be detected. Finally, high inhabitation rates against Streptococcus mutans and Candida albicans can be observed in 2 and 3. CONCLUSION: In all experiments, by elongating the spacer lengths of quaternary phosphorus salts, multifunctions were integrated in the quaternary phosphorus/bromoargentate hybrids, including greenish blue luminescence, repeatable photocurrent responses and durable antimicrobial activities with enhanced water stability. This work could provide a theoretical guide for the design of new biologically multifunctional materials.