Category: surface science

Nonspecific adsorption of ions and biomolecules mask the real surface charge of bacterial cells

February 15, 2020

Various proteins and biomolecules decorate the surface of bacterial cells. Whether tethered to the outer membrane of Gram-negative bacteria or adhering to the peptidoglycan layer of Gram-positive bacteria, these biomolecules endow the cell surface with an electrical charge and are responsible for various signalling and recognition processes mediated by cell surface receptors. However, in addition … More Nonspecific adsorption of ions and biomolecules mask the real surface charge of bacterial cells

Zeta potential measurement can be influenced by particle concentration

January 10, 2020

Zeta potential is commonly used as a proxy for cell surface charge, but is zeta potential dependent on particle concentration? The answer is yes in the case of high particle concentration.   From a theoretical standpoint, zeta potential measurement comes from the direct measurement of light scattered off moving particles in a fluid. In the … More Zeta potential measurement can be influenced by particle concentration

Electroosmotic flow in zeta potential analysis

January 3, 2020

Microelectrophoresis light scattering is commonly used to measure the zeta potential of cells, which is a proxy parameter for the cell surface charge. Briefly, the technique entails the measurement of movement of cells within a fluid upon application of an electric field. Thus, depending on the amount of surface charge present on cells, different rates … More Electroosmotic flow in zeta potential analysis

Biofouling of ships’ surface increase drag on ships and adds to fuel cost

December 4, 2019

Various marine microorganisms and macroscopic organisms adhere to ships’ surfaces through different methods such as the secretion of adhesion compounds or through direct adhesion. This process is known as biofouling and adds a layer of material that adhere to the ship surface. Given that the biofouling layer is irregular in shape, thickness and contours, it … More Biofouling of ships’ surface increase drag on ships and adds to fuel cost

How do droplets behave on a coated screen glass of smartphone and tablets?

June 3, 2019

Have you noted the behaviour of water droplets on the touchscreen of smartphone and tablets? If the surface of the touchscreen is hydrophobic, which means water hating, the water droplet will appear to be spherical as it could not spread on the touchscreen surface. On the other hand, if the surface of the touchscreen is … More How do droplets behave on a coated screen glass of smartphone and tablets?

Effect of wash buffers on zeta potential measurement of bacterial cells

March 19, 2018

Nonspecific adsorption of ions and metabolites from the growth medium on the bacterial cell surface is inevitable given the presence of various functional groups on the cell envelope. Thus, various wash buffers such as phosphate buffered saline and 0.1M sodium nitrate have been used in repeated steps of centrifugation and washing for removing the nonspecifically … More Effect of wash buffers on zeta potential measurement of bacterial cells