Professor Brian Cunningham's research group at the University of Illinois has created a technology for ultrasensitive detection of gold nanoparticles, allowing different assays and applications.
These single step, isothermal, room temperature, one-pot assays can process a sample volume as low as ~20 ul. These assays are performed with an inexpensive, small device based on a low intensity LED (no laser), that allows for simple data quantification by counting (no fancy imaging sensor needed) and multiplexing by sample splitting.
Applications of this technology include:
- Activate Capture and Digital Counting (AC+DC) for detection of miRNA, based on gold nanoparticles tags prepared with DNA toehold probes (DNA-AuNPs). (LOD = 100 aM, 2h; no purification and amplification required)
- Activate Capture and Digital Counting (AC+DC) for detection of proteins, based on secondary antibody-functionalized gold nanoparticles (2oAb-AuNPs) within 15 min (LOD = 10pg/ml) (pictured below)
- Targeting Recycling Amplification Process (TRAP) for miRNA detection, based on strand displacement reactions (LOD = 0.1aM, 20 min)
- Activate Cleve and Count (ACC) for ctDNA detection based on gold nanoparticles released after target recognition by CRISPR/Cas (LOD = 1zM, 60 min) (pictured below
Related Technology: Photonic Resonator Absorption Microscopy (PRAM)
Recent scientific publications include:
- A compact photonic resonator absorption microscope for point of care digital resolution nucleic acid molecular diagnostics
- Single-step, wash-free digital immunoassay for rapid quantitative analysis of serological antibody against SARS-CoV-2 by photonic resonator absorption microscopy
- Digital-resolution and highly sensitive detection of multiple exosomal small RNAs by DNA toehold probe-based photonic resonator absorption microscopy