Anisha GOKARNA, Yong Hwan KIM, Yong-Hoon CHO^*, Min Su LEE¹, In Cheol KANG², Hyun Kyu PARK³, Min Gon KIM³ and Bong Hyun CHUNG³

Nano-Bio-Photonics Laboratory, Department of Physics, Chungbuk National University, Cheongju 361-763, Korea
¹Chungbuk BIT Research-Oriented University Consortium, Chungbuk National University, Cheongju 361-763, Korea
²Protein Chip Research Laboratory, Department of Biological Science, College of Natural Science, Hoseo University, Asan 336-795, Korea
³Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, Korea

(Received November 15, 2005; Accepted March 13, 2006)

We demonstrate the fluorescence mapping of protein microarrays by the technique of scanning near-field optical microscopy (SNOM) and confocal microscopy. Micron sized spots (300 μm) of human Immunoglobulin G (hIgG) protein with and without a Cy3 dye labeling have been fabricated on glass substrates by an immobilization method which makes use of calixcrown derivatives termed Prolinker. We have also tried to probe into the well-known “doughnut effect” observed in fluorescence images of proteins using the SNOM technique. The topographic and fluorescence SNOM images revealed that the number of proteins at the boundary of the spot were more than at the center in the case of the microarray spot which showed brighter luminescence at the edge than at the center in the confocal image.

Key words: scanning near field optical microscopy, fluorescence, protein microarray, protein chip, confocal microscopy

^*E-mail address: yonghcho@chungbuk.ac.kr