A Single-Walled Carbon Nano-Tube/Chitosan Hydrogel Array for the Label-Free, Optical Detection of Protein-Protein Interactions

Technology   

The current invention details the fabrication of a label-free protein-protein microarray that uses single-walled carbon nanotube (SWNT) photoluminescence to transduce protein binding. Proteins are produced in situ via cell-free synthesis and directly immobilized on the SWNT/chitosan array, eliminating purification steps required by other techniques. Furthermore, protein-protein interactions are detected in a label-free manner. This invention uses a SWNT/chitosan microarray that optically reports binding of an analyte protein to the capture protein docked to the nickel complex wrapping the nanotube. This arrangement enables resolution of single protein binding events, the lowest detection limit of any protein array demonstrated to date.

Problem Addressed

Protein microarrays are a developing technology that shows significant promise for drug development and protein detection applications. However, current protein microarrays suffer from a variety of drawbacks, such as relying on the use of antibodies for protein capture, requiring the use of a label or tag and limited amounts of purified proteins.

Advantages 

• Does not require labeling of the target analyte protein, which can perturb protein-protein interactions of interest
• Suitable for any protein-protein interactions, not just antigen-antibody pairs
• Capability to detect single protein binding events
• Real-time detection
• High-throughput detection of protein-protein interactions
• Eliminates protein preparation and purification since synthesis is done directly on the array; thus it is simple and cheap