Mutagenic activity of quaternary ammonium salt derivatives of carbohydrates

Enhancing Implantable Medical Devices: Surface Functionalization of Titanium with Quaternary Ammonium Salts for Antibacterial Adhesion Properties

Bacterial colonization of titanium-based materials used in implantable medical devices represents a significant challenge in the dental and orthopedic fields, often leading to infections and implant failure. This study reports the surface modification of titanium discs with ammonium salts containing carbon atom chains of different lengths (from 6 to 12) to provide antibacterial properties to the modified metal surfaces while maintaining their biocompatibility. The chemically modified samples have been characterized by ATR-FTIR and SEM-EDX analyses and evaluated for roughness and hydrophilic behavior. This surface modification not only provides hydrophobic properties to titanium surfaces but also introduces a hindering environment for bacterial adhesion. Antibacterial tests performed against methicillin-sensitive and methicillin-resistant Staphylococcus aureus strains demonstrated a proportional increase in antibacterial activity with increasing carbon chain length. The best antibacterial performance is reported for the sample containing 12 carbon atoms (Ti-ADTEAB), which showed inhibition values of 87.5 and 86.6% for the sensitive and resistant strains, respectively. The results suggest that this surface modification could lead to a new generation of implantable medical devices with improved patient outcomes by reducing the risk of postoperative infections.

Synthesis, Antimicrobial and Mutagenic Activity of a New Class of d-Xylopyranosides

Eight N-[2-(2',3',4'-tri-O-acetyl-α/β-d-xylopyranosyloxy)ethyl]ammonium bromides, a new class of d-xylopyranosides containing a quaternary ammonium aglycone, were obtained. Their complete structure was confirmed using NMR spectroscopy (¹H, ¹³C, COSY and HSQC) and high-resolution mass spectrometry (HRMS). An antimicrobial activity against fungi (Candida albicans, Candida glabrata) and bacteria (Staphylococcus aureus, Escherichia coli) and a mutagenic Ames test with Salmonella typhimurium TA 98 strain were performed for the obtained compounds. The greatest activity against the tested microorganisms was shown by glycosides with the longest (octyl) hydrocarbon chain in ammonium salt. None of the tested compounds exhibited mutagenic activity in the Ames test.

Systematic synthesis and characterization of a series of different bromoalkylglycosides by Fischer glycosylation

In order to investigate the possibilities of Fischer glycosylation towards the synthesis of bromoalkylglycosides we performed a variety of different reactions resulting in a small library of 16 different glycosides. Using standardized reaction conditions we could gain a broad range of results from small to higher yields. Finally we randomly selected three reactions and performed them with higher amounts of bromoalcohol resulting in significantly better yields, showing the optimization potential of these basic research work.