Pristine and Antibiotic-Loaded Nanosheets/Nanoneedles-Based Boron Nitride Films as a Promising Platform to Suppress Bacterial and Fungal Infections
ACS APPLIED MATERIALS & INTERFACES
Authors: Gudz, Kristina Y.; Permyakova, Elizaveta S.; Matveev, Andrei T.; Bondarev, Andrey, V; Manakhov, Anton M.; Sidorenko, Daria A.; Filippovich, Svetlana Y.; Brouchkov, Anatoli, V; Golberg, Dmitri, V; Ignatov, Sergei G.; Shtansky, Dmitry, V
Abstract
In recent years, bacteria inactivation during their direct physical contact with surface nanotopography has become one of the promising strategies for fighting infection. Contact-killing ability has been reported for several nanostructured surfaces, e.g., black silicon, carbon nanotubes, zinc oxide nanorods, and copper oxide nanosheets. Herein, we demonstrate that Gram-negative antibiotic-resistant Escherichia coli (E. coli) bacteria are killed as a result of their physical destruction while contacting nanostructured h-BN surfaces. BN films, made of spherical nanoparticles formed by numerous nanosheets and nanoneedles with a thickness <15 nm, have been obtained through a reaction of ammonia with amorphous boron. The contact-killing bactericidal effect of BN nanostructures has been compared with a toxic effect of gentamicin released from them. For a wider protection against bacterial and fungal infection, the films have been saturated with a mixture of gentamicin and amphotericin B. Such BN films demonstrate a high antibiotic/antimycotic agent loading capacity and a fast initial and sustained release of therapeutic agents for 170-260 h depending on the loaded dose. The pristine BN films possess high antibacterial activity against E. coli K-261 strain at their initial concentration of 10(4) cells/mL, attaining >99% inactivation of colony forming units after 24 h, same as gentamicin-loaded (150 mu g/cm(2)) BN sample. The BN films loaded with a mixture of gentamicin (150 and 300 mu g/cm(2)) and amphotericin B (100 mu g/cm(2)) effectively inhibit the growth of E. coli K-261 and Neurospora crassa strains. During immersion in the normal saline solution, the BN film generates reactive oxygen species (ROS), which can lead to accelerated oxidative stress at the site of physical cell damage. The obtained results are valuable for further development of nanostructured surfaces having contact killing, ROS, and biocide release abilities.
Early and Late Efficacy on Wound Healing of Silver Nanoparticle Gel in Males after Circumcision
JOURNAL OF CLINICAL MEDICINE
Authors: Balzarro, Matteo; Rubilotta, Emanuele; Trabacchin, Nicolo; Soldano, Antonio; Cerrato, Clara; Migliorini, Filippo; Mancini, Vito; Pastore, Antonio Luigi; Carbone, Antonio; Cormio, Luigi; Carrieri, Giuseppe; Antonelli, Alessandro
Abstract
We evaluate the early and late safety and efficacy of silver nanoparticle (AgNPs) in wound healing after circumcision. This multicenter prospective comparative non-randomized observational study compares wound dressing with AgNPs (group A) vs. gentamicin cream (group B). Follow-up included objective evaluation at 10 and 30 days by the Southampton Scoring System (SSS) and Stony Brook Scar Evaluation Scale (SBSES). We enrolled 392 males: 194 in group A, and 198 in group B. At 10 days follow-up, in group A, the SSS scale was grade 1 in 49.5% and grade 2 in the remaining; meanwhile, in group B, grade 1 was in 58%, grade 2 in 34.3%, and grade 4 in 7.6%. At 30 days follow-up, grade 1 healing was 97.4% and 98.4% in group A and B, respectively. At 10 days follow-up, the mean SBSES score was 3.58 and 3.69 in group A and B, respectively; while at 30 days follow-up, 4.81 and 4.76 in group A and B, respectively. Only in group B did 7.6% of males have antibiotic therapy due to pus discharge. No patients needed surgical wound revision. AgNPs led to a late but safer healing, they were non-inferior to the antibiotic cream wound dressing efficacy, and they avoided pus discharge and the need for oral antibiotics due to their polymer material.