Monitoring of adsorption behaviors of bovine serum albumin onto a stainless steel surface by the quartz crystal microbalance based on admittance analysis

Abstract

The adsorption process of bovine serum albumin (BSA) onto a stainless steel surface was investigated using the quartz crystal microbalance based on admittance analysis. The adhered mass change ∆m increased with time as a result of contacting the BSA solution, and considerably long period (>2 h) was required for the attainment of the asymptotic values of ∆m as well as dissipation factor ∆D. The relation between ΔD and Δm suggested that the layer of adsorbed BSA molecules became stiffer with increasing time at higher BSA concentration. The relation between Δm after 2 h and the final BSA concentration was described well by the Langmuir adsorption isotherm. However, the time course of Δm clearly deviated from the Langmuir adsorption model. The stretched exponential function model described the time course of Δm well although it was an empirical one.

Designing a Bioinert Surface by Simple Coating with Cholesterol End-Modified Poly(ethylene glycol)

“…Notably, from the QCM-A measurements to convert alterations in the frequency (Δ f ) into changes in the mass (Δ m ) by the Saurbery equation − (Figure S8), the graft density of Chol-U-Pr-mPEG (2k) on the PP surface was calculated to be 1.1 chains/nm 2 . The resulting graft density was higher than that (∼0.6 chains/nm 2 ) of a diblock copolymer poly­[( N , N -dimethylacrylamide) 15 - co -( N -3,4-dihydroxyphenethyl acrylamide) 2 ]- b -mPEG (2k), PDN-mPEG (2k), by the representative drop-coating grafting to method onto a mica surface .…”

Label-Free Protein Detection by Micro-Acoustic Biosensor Coupled with Electrical Field Sorting. Theoretical Study in Urine Models

“…Along with the basic molecular properties in solutions, spontaneous adsorption of proteins onto liquid-solid interfaces should always be considered thoroughly while developing various sensors for analysis of biological fluids because it strongly influences chemical, mechanical, and electrical properties of metal and dielectric surfaces. This phenomenon has been extensively investigated both theoretically and experimentally [82][83][84]; a plethora of biochemical, radiochemical, electrochemical, optical, and acoustic techniques have been applied including enzyme-linked immunosorbent assay (ELISA) [85], radiolabelling [86], ellipsometry [87], total internal reflection fluorescence (TIRF) [88], surface plasmon resonance (SPR) [89], electrochemical quartz crystal nanobalance (EQCN) [90], and quartz crystal microbalance (QCM) [55,91], and polarization modulation infrared reflection absorption spectroscopy (PM-IRRAS) [92].…”

“…Excited at a shear bulk vibration mode, its resonant frequency shifts in accordance with interface loading. For bioliquid characterization, QCM was used to detect proteins in some works [53][54][55]. Some modern QCM biosensors use a sensitive or recognition layer to enhance sensitivity and selectivity for specific ingredients in liquid sample.…”

Radial Wicking of Biological Fluids in Paper

“…10 Also, the significant protein content and lipid component of blood plasma will adsorb onto both solid− liquid and liquid−vapor interfaces, affecting the contact angle, surface tension, and viscosity of the system nonuniformly. 11,12 The most abundant protein in blood is albumin 13 and has been shown to significantly impact wicking in paper. 11 Wicking is caused by a negative pressure produced by the curved meniscus at the air−liquid interface between pores.…”

“…The cell component of blood introduces rheological changes such as a shear-thinning viscosity and granularity caused by the presence of highly deformable red blood cells (RBCs) . Also, the significant protein content and lipid component of blood plasma will adsorb onto both solid–liquid and liquid–vapor interfaces, affecting the contact angle, surface tension, and viscosity of the system nonuniformly. , The most abundant protein in blood is albumin and has been shown to significantly impact wicking in paper …”