Fibrinogen Monolayers on Mica Studied via the Streaming Potential and Colloid Deposition Methods
نویسندگان
چکیده
The streaming potential and the colloid particle deposition (referred to as colloid enhancement CE) methods were applied to characterize fibrinogen (Fb) monolayers on mica, produced by controlled adsorption under diffusion transport. The surface concentration of Fb was determined directly by AFM enumeration of single molecules adsorbed over the substrate surface. It was proven that Fb adsorbed irreversibly on mica for various pH with the rate governed by bulk transport. The electrokinetic properties of Fb monolayers produced in this way were studied using the streaming potential method. The dependence of the apparent zeta potential of Fb monolayers was determined as a function of the coverage. It was shown that for pH = 3.5 the initial negative zeta potential of the mica substrate was converted to positive for Fb coverage exceeding 0.16 (see Fig.1.).
منابع مشابه
Streaming potential studies of colloid, polyelectrolyte and protein deposition.
Recent developments in the electrokinetic determination of particle, protein and polyelectrolyte monolayers at solid/electrolyte interfaces, are reviewed. Illustrative theoretical results characterizing particle transport to interfaces are presented, especially analytical formulae for the limiting flux under various deposition regimes and expressions for diffusion coefficients of various partic...
متن کاملStability of silver nanoparticle monolayers determined by in situ streaming potential measurements
ABSTRACT A silver particle suspension obtained by a chemical reduction was used in this work. Monolayers of these particles (average size 28 nm) on mica modified by poly(allylamine hydrochloride) were produced under diffusion-controlled transport. Monolayer coverages, quantitatively determined by atomic force microscopy (AFM) and SEM, was regulated by adjusting the nanoparticle deposition time ...
متن کاملSelf-assembled silver nanoparticles monolayers on mica-AFM, SEM, and electrokinetic characteristics
A monodisperse silver particle suspension was produced by a chemical reduction method in an aqueous medium using sodium citrate. The average particle size determined by dynamic light scattering (DLS), transmission electron microscopy (TEM), and atomic force microscopy (AFM) was 28.5 nm. The DLS measurements confirmed that the suspension was stable for the ionic strength up to 3 × 10-2 M NaCl. T...
متن کاملMicropatterned charge heterogeneities via vapor deposition of aminosilanes.
Aminosilanes are routinely employed for charge reversal or to create coupling layers on oxide surfaces. We present a chemical vapor deposition method to pattern mica surfaces with regions of high-quality aminosilane (3-aminopropyltriethoxysilane, APTES) monolayers. The approach relies on the vapor deposition of an aminosilane through a patterned array of through-holes in a PDMS (poly(dimethylsi...
متن کاملInfluence of electrostatic interaction on fibrinogen adsorption on gold studied by imaging ellipsometry combined with electrochemical methods.
Imaging ellipsometry was combined with electrochemical methods for studying electrostatic interactions of protein and solid surfaces. The potential of zero charge for gold-coated silicon wafer/solution interfaces wad determined by AC impedance method. The potential of the gold-coated silicon wafer was controlled at the potential of zero charge, and the adsorption of fibrinogen on the potential-...
متن کامل