Chlorhexidine possesses unique cytotoxic actions in rat thymic lymphocytes: Its relation with electrochemical property of membranes

Supramolecularly assisted chlorhexidine-bacterial membrane interaction with enhanced antibacterial activity and reduced side effects

Bacterial infection has emerged as a grievous threat to public health, and lots of antibacterial agents were developed to solve this issue. However, enhancing the antibacterial activity of antibacterial agents while reducing their side effects remains a challenge. Herein, a supramolecular antibacterial agent based on the host-guest interaction between cucurbit[7]uril (CB[7]) and chlorhexidine (CHX) was designed. CHX can be encapsulated in the cavity of CB[7] to form a 1:3 host-guest complex (CHX-3CB[7]). It was amazingly found that this supramolecular complex could display higher antibacterial activity than CHX alone. Electrospray mass spectrometry and UV-vis spectra revealed that the introduction of CB[7] promoted the protonation of N-atoms on CHX, resulting in stronger ion interaction with phospholipids and thus enhancing the destruction of the bacterial membrane. Scanning electron microscopy (SEM), surface ζ-potentials and outer/inner membrane integrity assays also reveal that the introduction of CB[7] aggravates the rupture of membrane. What is more, the cytotoxicity and irritation of CHX were decreased by forming the host-guest complex with CB[7]. This work provides a paradigm for enhancing antibacterial activity and reducing side effects of drugs through supramolecular chemistry.

Evaluation of 4 Presurgical Skin Preparation Methods in Mice

Mice routinely undergo surgical procedures for use in research; however, studies of skin preparation methods to achieve antisepsis are rare. The present study evaluated 4 skin preparation treatments: depilatory agent followed by povidone-iodine and alcohol scrub; depilatory agent followed by povidone-iodine and saline scrub; electric clippers followed by povidone-iodine and alcohol scrub; and electric clippers followed by povidone-iodine and saline scrub. Swabs for bacterial culture were obtained immediately after hair removal and after scrubbing to measure the reduction in bacterial load. Full-thickness incisions were assigned ASEPSIS wound scores and examined histologically on days 0, 1, and 7 after surgery. Neither bacterial load growth nor ASEPSIS wound scores differed among any of the treatments. Histopathology revealed statistically significant but biologically irrelevant differences. Overall all treatment methods achieved acceptable bacterial load reduction and surgical site healing.