The Walt lab pioneered the use of microwell arrays for ultra-sensitive biomarker detection and analysis, such as proteins and microRNAs. The technique, known as Single Molecule Arrays (Simoa), is based on digital enzyme-linked immunosorbent assay (ELISA) and can improve the limit of detection of conventional ELISA by about 1000 folds. Using Simoa, the Walt lab is currently developing blood-based tests for various diseases including breast cancer, Parkinson’s, Tuberculosis and etc. Another application of this effort is an integrated diagnostic platform for performing medical diagnostics using saliva as sample instead of blood, for example, in the study of oral feeding. The Simoa platform can also be used to study living cells, both as cell populations and as individual cells when integrated with microfluidics. The Walt lab is interested in studying the behavior of large numbers of cells to understand the distribution of cell behaviors in a population.
In the past, the Walt lab has investigated the application of using high-density optical fibers as microsensors and nanosensors to perform nucleic acid and protein analysis. The Walt lab also revolutionized the process of genetic and proteomic sequencing, enabling the cost of DNA sequencing and genotyping to plummet nearly a million fold in the last decade. This technology is now the gold standard for sequencing in a wide variety of applications including screening embryos for genetic defects before in vitro fertilization, studying disease in preserved/frozen tissues, improving crop disease resistance, and identifying individuals’ metabolic profiles to ensure proper drug dosage.