an efficient covalent coating on glass slides for preparation of optical oligonucleotide microarrays

objective(s): microarrays are potential analyzing tools for genomics and proteomics researches, which is in needed of suitable substrate for coating and also hybridization of biomolecules.   materials and methods: in this research, a thin film of oxidized agarose was prepared on the glass slides which previously coated with poly-l-lysine (pll). some of the aldehyde groups of the activated agarose linked covalently to pll amine groups; also bound to the amino groups of biomolecules. these linkages were fixed by uv irradiation. the prepared substrates were compared to only agarose-coated and pll-coated slides. results:   results on atomic force microscope (afm) demonstrated that agarose provided three-dimensional surface which had higher loading and bindig capacity for biomolecules than pll-coated surface which had two-dimensional surface. in addition, the signal-to-noise ratio in hybridization reactions performed on the agarose-pll coated substrates increased two fold and four fold compared to agarose and pll coated substrates, respectively.   conclusion: the agarose-pll microarrays had the highest signal (2546) and lowest background signal (205) in hybridization, suggesting that the prepared slides are suitable in analyzing wide concentration range of analytes.