Submicron Streptavidin Patterns for Protein Assembly

Abstract

Micron and submicron-scale features of aldehyde functionality were fabricated in polymer films by photolithography to develop a platform for protein immobilization and assembly at a biologically relevant scale. Films containing the pH-reactive polymer poly(3,3'-diethoxypropyl methacrylate) and a photoacid generator (PAG) were patterned from 500 nm to 40 mum by exposure to 365 nm (i-line) light. Upon PAG activation and hydrolysis of acetals, aldehyde groups formed. After the films were incubated with a biotinylated aldehyde reactive probe, the X-ray photoelectron spectroscopy results were consistent with biotin being attached to the surface. The background was subsequently passivated by flood exposure and incubation with an aminooxy-terminated poly(ethylene glycol), resulting in a 98% reduction in nonspecific protein adsorption. Protein patterning and assembly was demonstrated using streptavidin, biotinylated anthrax toxin receptor-1, and the protective antigen moiety of anthrax toxin and confirmed by fluorescence microscopy and atomic force microscopy (AFM). AFM demonstrated that 500 nm protein features were achieved. Because of the abundance of biotinylated proteins, this methodology provides a platform for protein immobilization and assembly for various applications in biotechnology.

Controlled Oxidation, Biofunctionalization, and Patterning of Alkyl Monolayers on Silicon and Silicon Nitride Surfaces using Plasma Treatment

“…As depicted in Figure 9, avidin still has some of its 4 recognition sites available after a specific adsorption with the immobilized biotin. 68 The final saturation of free surface sites with BSA ensures that no protein will adsorb unspecifically during the reflectometry measurements. 22 The reflectometry measurements displayed in Figure 10 show the specific interaction of biotin-labeled BSA with avidinfunctionalized silicon nitride surfaces: during the first phase of exposure to unlabeled BSA, no adsorption occurred, because all the areas available for nonspecific adsorption have already been saturated, either by avidin attachment or by the subsequent incubation with BSA.…”

Advances in the Development of Supramolecular Polymeric Biomaterials

“…In a subsequent final step, any biotinylated compound can be immobilized onto the streptavidin, giving rise to highly controlled surface functionalization with bioactive compounds. 10 As a special class of proteins, growth factors have increased interest in recent years, since they are involved in many processes. The therapeutic potential of growth factors holds great potential for applications in regenerative medicine.…”

Nanotopography Engineering on Homopolymeric Surfaces Using Cold Plasma Generated Charges

“…Self-assembling nanotechniques [27][28][29][30] are used to generate masks for selective processing of the surface (e.g., etching) or in the direct generation of nanotopography-containing substrates. Reactive chemical generation of nanotopography [31] and nanoparticle-induced nanopatterns [32] have also been used for bioapplications.…”