The deposit patterns derived from droplet evaporation allow current development of medical tests and new strategies for diagnostic in patients. For such purpose, the development and implementation of algorithms capable of characterizing and differentiating deposits are crucial elements. We report the study of deposit patterns formed by the droplet evaporation of binary mixtures of proteins containing NaCl. Optical microscopy reveals aggregates such as tip arrow-shaped, dendritic and semi-rosette patterns, needle-like and scalloped lines structures, as well as star-like and prism-shaped salt crystals. We use the first-order statistics (FOS) and gray level co-occurrence matrix (GLCM) to characterize the complex texture of deposit patterns. Three significant findings arise from this analysis: first, the FOS and GLCM parameters structurally characterize protein deposits. Secondly, they conform to simple exponential laws that change as a function of the NaCl concentration. Finally, the parameters are capable of revealing the different structural changes that occur during the droplet evaporation.

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The motility of mouse sperm increases with green light irradiation at 37 °C, but decreases at 10 °C.

We took advantage of the microflow hydrodynamics in the evaporation of sessile droplets to increase the height uniformity of thin lipid films for the subsequent electroformation of defect-free giant unilamellar vesicles (GUV). By serially casting progressively larger liposome suspension droplets on the same spot of an indium-tin-oxide (ITO) electrode, we managed to leverage the coffee ring effect (CRE) in the evaporation of each droplet to generate a smeared multilayer film of uniform thickness. This multidroplet technique of lipid film formation outperformed the traditional single-droplet deposition, improving the final quality of electroformed GUV samples. The proposed film formation technique constitutes a solvent-free method that results in a dramatic reduction (∼20×) in the appearance of undesirable structures like nonspherical (NSV), multilamellar (MLV), and multivesicular (MVV) vesicles.

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