Photoactivatable copolymers of vinylbenzyl thiocyanate as immobilization matrix for biochips.
Biochip surfaces for immobilization of DNA and proteins require reactive polymers with high immobilization capacity and low nonspecific binding. Most reactive surfaces consist of matrixes that provide epoxy, aldehyde, or amino functions for biomolecule binding. The most widely used oligonucleotide modification is a C6-amino link. The high reactivity of isothiocyanate groups (NCS) toward amines was therefore the motivation to employ photogenerated NCS groups as binding sites for NH(2)-terminated oligonucleotides. Photosensitive poly(styrene-co-4-vinylbenzyl thiocyanate) (PST-co-VBT) was synthesized and applied as novel material for DNA and protein immobilization. The immobilization capacity of PST-co-VBT was a function of UV energy density used for photoactivation and was approximately 80% at 450 mJ cm(-)(2) (lambda(ex) = 254 nm). This surface was superior to tested commercial chip surfaces in signal-to-noise-ratio and reproducibility. Print buffer and spacer length were optimized for maximum fluorescence signal with DNA and proteins. UV exposure conditions and oligonucleotide modification were correlated, showing that this photochemical approach can be successfully applied for surface patterning of biochips.
Biotechnology Unit and Environmental Research Unit, Division of Environmental and Life Sciences, ARC Seibersdorf Research GmbH, A-2444 Seibersdorf, Austria. claudia.preininger@arcs.ac.at
Claudia
C
Preininger
Ursula
U
Sauer
Wolfgang
W
Kern
Joachim
J
Dayteg
D001483:Base Sequence; D017931:DNA Primers; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis; D010777:Photochemistry; D011108:Polymers / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D012680:Sensitivity and Specificity
D017931:DNA Primers; D011108:Polymers; D011137:Polystyrenes; C502228:poly(styrene-co-4-vinylbenzyl thiocyanate)