Surface properties of Vancomycin after interaction with laser beams

• A novel method to evidence surface active compounds in water-VCM solutions produced by exposure to UV laser, measuring DIT at air/solution interface is reported.
• Production and presence of amphiphilic molecules without separating them from solution are reported.
• Four hydrophobic compounds are identified and their chemical structures are proposed.
• Surface activity modifications may lead to variations of VCM solutions wetting properties.

This study presents results about UV laser beam interaction with Vancomycin (VCM) solutions in ultrapure water performed on bulk samples (5 mL). Photoproducts and molecular fragments resulting from the parent VCM and generated by exposure to 266 nm are evidenced by UV–vis absorption and FTIR spectroscopy and liquid chromatography electro spray ionization time-of-flight mass spectrometry (LC/ESI-TOF-MS) measurements. A novel method is reported to characterize surface active compounds produced in VCM solutions during exposure to UV laser radiation, by measuring in real time the dynamic interfacial tension of the irradiated solutions in emerging, constant volume bubble configuration. This shows that amphiphilic photoproducts are generated after the interaction of VCM molecules with laser beam that migrate at the interface air bubble/VCM solution. They accumulate at the interface leading at transition surface effects. In the paper four such amphiphilic photoproducts were identified and their chemical structures were proposed.

Figure optionsDownload as PowerPoint slide