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 (۲۵۴۶) and lowest background signal (۲۰۵) in hybridization, suggesting that the prepared slides are suitable in analyzing wide concentration range of analytes.  

Keywords:

Agarose , Coating , Microarray , PLL , Signal-to-noise