Due to non-specific interactions of proteins with surfaces, microarray performance and assay sensitivity strongly depend on carefully adjusted slide coatings. Instead of using any commercial product, PEPperPRINT's surface scientists developed a new proprietary glass slide coating for the PEPperCHIP® peptide microarray platform that fully complies with our requirements for high quality assays and data reproducibility.
Our PEPperSlide®glass slide coatings are based on 3D graft copolymer films that are generated by atom transfer radical polymerization. The coatings are routinely analyzed by x-ray photoelectron spectroscopy to determine atomic composition and by ellipsometry to investigate film thickness and homogeneity. Commonly applied contact angle measurements are regarded as inadequate quality control. Graft polymerization is followed by derivatization with amine groups for combinatorial Fmoc peptide synthesis; the amine loading is routinely analyzed and controlled by UV/Vis spectrometry. Therefore, the benefits of our PEPperSlide® glass slides are summarized below:
- Tunable coating properties by adjusted film thicknesses and copolymer compositions
- Inherent blocking of non-specific protein interactions
- High and adjustable loading of functional groups
- Superior signal-to-noise ratios
- Wide dynamic range
- Minimal background fluorescence
- High array reproducibility due to stringent and in-depth QC
- Preservation of native protein conformation and functionality
- Compatible with various immobilization strategies and microarray probes
- Thorough chemical stability and compatibility with Fmoc chemistry
PEPperSlide® glass slide coatings are, thus, superior in terms of flexibility, microarray performance and assay sensitivity, and are simply the ideal substrate for peptide microarray-based immunoassays. This custom and well-adjusted coating is, hence, another unique feature and strong benefit of PEPperPRINT's peptide microarray platform PEPperCHIP®.