Microdroplets of Laser Irradiated Drug Solutions: Surface Tension and Contact Angle

Precision measurements of surface tension and contact angle were performed on some medicines from the phenothiazine class (chlorpromazine, promethazine, and thioridazine) at different temperatures and concentrations in water, using the pending drop and the sessile drop methods. A specialised system DSA 100 (Krüss) was used for these measurements. Precautions were taken for an optimal acquisition of images (thermal isolation and heated windows of the chamber holding the studied droplets). Contact angles either static or dynamic were determined. Density measurements were also performed for the solutions. The same experiments were performed on these solutions after UV laser irradiation. The obtained values were discussed in comparison with the solvent behaviour and with the behaviour of other drugs (of alizarin dye class) as well. The average values of the advancing and receding angle, determined using a home developed program, are here presented for the first time.

Keywords: Chlorpromazine, CPZ, Daunorubicin, Density measurement, Doxorubicin, Drop interface, Dynamic contact angle, Laser irradiation, Nd:YAG laser, Pendent drop, Polytetrafluoroethylene, PTFE, Promethazine, PMZ, Sessile drop, Surface tension, Thioridazine, TZ, Ultrapure water, Vancomycin.