Interaction of solutions containing phenothiazines exposed to laser radiation with materials surfaces, in view of biomedical applications

• Aqueous solutions containing phenothiazines (chlorpromazine, promazine and promethazine) were exposed to 266 nm pulsed laser radiation.
• Exposed phenothiazines solutions were studied by: pH measurements, UV–vis-NIR absorption spectroscopy, laser induced fluorescence and thin layer chromatography.
• Surface tension measurements on phenothiazines droplets have been performed in order to examine the surface active characteristics of the medicine solutions.
• Contact angle measurements for droplets were completed on three different solid surfaces (cotton, polyester, and Parafilm M) to investigate their wettability in view of biomedical applications.

Phenothiazine drugs – chlorpromazine (CPZ), promazine (PZ) and promethazine (PMZ) – were exposed to 266 nm (fourth harmonic of the Nd:YAG pulsed laser radiation) in order to be modified at molecular level and to produce an enhancement of their antibacterial activity. The irradiated samples were analysed by several methods: pH and surface tension measurements, UV–vis-NIR absorption spectroscopy, laser induced fluorescence and thin layer chromatography. The purpose of these investigations was to study and describe the modified properties of the medicines to further investigate their specific interactions with materials such as cotton, polyester and Parafilm M as a model smooth surface. The textile materials may be impregnated with phenothiazines drug solutions exposed to laser radiation in order to be used in treatments applied on the surface of the organism. Some of the phenothiazines solutions exposed prolonged time intervals to laser radiation have much better activity against several bacteria. Therefore, in the paper, it is reported the wetting behaviour of CPZ, PZ and PMZ solutions, irradiated for time intervals between 1 and 240 min, on the surfaces of the three textures in order to draw a conclusion about their wettability as a function of time.

Figure optionsDownload high-quality image (145 K)Download as PowerPoint slide