Dendrimer-Activated Surfaces for High Density and High Activity Protein Chip Applications

• Published in: Langmuir Vol. 20; no. 15; pp. 6075 - 6079
• Main Authors: Pathak, Srikant, Singh, Anup K, McElhanon, James R, Dentinger, Paul M
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 20.07.2004
• Subjects: Alkaline Phosphatase - chemistry; Chemical Phenomena; Chemistry, Physical; Dendrimers - chemistry; Imidazoles - chemistry; Immobilized Proteins; Models, Molecular; Molecular Structure; Polypropylenes - chemistry; Protein Array Analysis - methods; Proteins - chemistry; Silanes - chemistry; Surface Properties
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la036271f

Highly functional Si and glass surfaces for protein immobilization have been prepared by a facile activation of native surface silanol groups. Poly(propyleneimine) dendrimers of generations 1−5 were immobilized onto the surface using a facile room-temperature coupling procedure that involved activation of native silanol groups of glass using 1,1‘-carbonyldiimidazole under anhydrous conditions. The dendrimer-coated surfaces were used to immobilize proteins and were characterized with respect to surface loading and activity. A number of different chemical, physical, and biochemical techniques including contact angle measurement, ellipsometry, and fluorescence microscopy were used to characterize the resulting surfaces. Increasing the dendrimer generation past G-3 led to increased surface amine content, immobilized protein concentration, and the activity of immobilized alkaline phosphatase (used as a test system). Very high activity of the immobilized proteins in the case of higher generation (G-4 and G-5) dendrimers led us to conclude that such an approach has true potential for creating highly functional surfaces for protein chip applications.