Si chips provide a large sensor area (5x7mm) and guide markings for robotic spotters for printing a microarray of ligands. Reference regions and rulers enable automated image analysis and quantification. Easy and intuitive assembly of disposable cartridges at room temperature protects the biological activity of immobilized ligands.
Oxide surface provides compatibility with glass surface chemistries. Multiple surface chemistry coatings can be used on the same IRIS chip simultaneously.
IRIS allows the user to quickly understand which surface chemistry would better suit any specific ligand/analyte combination. Furthermore, IRIS eliminates the limitation regarding the number of molecules with different chemistries that can be immobilized on the same support.
Examples with small MW analytes:
We have demonstrated high signal-to-noise ratio measurements of 1.4 kDa V5 peptide binding to immobilized antibodies. These results display average signal from 60 spots indicating >10-plex capability for peptide and small molecule analytes. Biotin (244 Da) at analyte concentrations of 1pM, 1nM and 1µM binding to immobilized avidin validates the high sensitivity.
Compatible with Fluorescence and Chemiluminescence:
A dual detection system for protein arrays that combines IRIS with chemiluminescence for hepatitis B surface antigen has been developed. The dual detection system allows to combine the analytical capability of optical interference detection with the established clinical utility of chemiluminescence detection (*). IRIS chips enhance fluorescence intensity by optical interference (†).
Dynamic Detection of Cytokine Secretion:
Monitoring cytokine release by cells allows the investigation of cellular response to specific external stimuli, such as pathogens or candidate drugs. We demonstrated a quantitative dynamic detection of interleukine-6 (IL-6), a pro-inflammatory cytokine and “mass tags” can be used concurrently with the target analyte to eliminate an additional wash and binding step. Successful label-free detection of IL-6 in cell culture medium (with 10% serum) has been reported (‡).