Chiral Sulfur Nanosheets for Dual-Selective Inhibition of Gram-Positive Bacteria

Abstract

Elemental sulfur is the oldest known antimicrobial agent. However, conventional sulfur in the clinic suffers from poor aqueous solubility and limited antibacterial activity, greatly hindering its practical use. Herein, we report a reform strategy coupling dimension engineering with chirality transfer to convert conventional 3D sulfur particles into chiral 2D sulfur nanosheets (S-NSs), which exhibit 50-fold improvement of antibacterial capability and dualselective inhibition against Gram-positive bacteria. Benefiting from the inherent selectivity of S-NSs and chirality selectivity from decorated Dhistidine, the obtained chiral S-NSs are proven to precisely kill Gram-positive drug-resistant bacteria, while no obvious bacterial inhibition is observed for Gram-negative bacteria. Mechanism studies reveal that S-NSs produce numerous reactive oxygen specipoes and hydrogen sulfide after incubation with bacteria, thus causing bacterial membrane destruction, respiratory chain damage, and ATP production inhibition. Upon spraying chiral S-NSs dispersions onto MRSA-infected wounds, the skin healing process was greatly accelerated in 8 days due to metabolism inhibition and oxidative damage of bacteria, indicating the excellent treatment efficiency of MRSA-infected wounds. This work converts the traditional well-known sulfur into modern antibacterial agents with a superior Gram-selectivity bactericidal capability.

Thiol ligand-mediated exfoliation of bulk sulfur to nanosheets and nanodots: applications in antibacterial activity

“…Since there are very few reports on the antibacterial properties of sulfur nanosheets, we were eager to investigate the antibacterial effectiveness of BA-exfoliated nanosheets. 58 During the assessment of the exfoliation process, we observed that a longer exfoliation time was required with BA to transform the bulk sulfur. It took 150 min to be exfoliated into nanosheets, and after 180 min, nanodots started to form (Fig.…”

“…This MIC value is noteworthy and compares favorably with previously reported data on sulfur nanosheets (100 μg mL −1 ). 58 Furthermore, we quantified the ability of these nanosheets to kill bacteria by streaking the treated solution onto agar plates. The concentration at which no bacterial colonies formed on the agar plate indicated the minimum bactericidal concentration (MBC), which was determined to be 31.3 μg mL −1 for the BASNs (Fig.…”

Tailoring the energy gap to promote long wavelength emission of nitrogen-doped sulfur quantum dots via dual functional ethylenediamine

“…3B), in which the peaks at 161.5 eV and 162.6 eV were attributed to zero-valent sulfur and the peaks at 167.5 eV and 168.5 eV can be assigned to the oxidation state of sulfur such as SO 2 À (2p 2/3 ), SO 2 À (2p 1/2 ), or SO 3 2À (2p 2/3 ). 3,14,45 The oxidation state of sulfur arises from the presence of the atmospheric oxygen. Fig.…”

Efficient Mechanochemical Conversion of Elemental Sulfur to Circularly Polarized Luminescent Sulfur Quantum Dots

“…However, the fabrication of inherently chiral materials remains challenging. Of late, chirality transfer to the conventional sulfur particles (3D structure) into chiral sulfur nanosheets (2D structure) has improved their dispersibility in aqueous medium and antibacterial properties by 50-fold . Notably, the earth-abundant element bulk sulfur has been widely employed in various synthesis techniques as a primary precursor of Sdots and still suffers from a few shortcomings such as complex synthesis procedures.…”