This Mentored Quantitative Research Development Award will facilitate the candidate, an engineer, to become a biologist. It will be achieved by taking courses to gain fundamental knowledge in biology/medicine and developing relevant research skills via mentored research. The selected courses will include core courses encompassing the fundamentals of biomedical sciences and advanced courses. Biomedical research experience will be obtained through lab rotations in the mentor's and co-mentor's laboratories. The mentored research is to develop a platform to concentrate and enrich acute leukemia cells for detection of minimal residual disease (MRD). MRD refers to the presence of residual malignant cells that remain in the patient during treatment or after treatment when the patient is in remission (no symptoms or signs of disease). The current benchmark method is not sufficiently sensitive for detecting all remaining tumor cells in peripheral blood. As a result, a platform with a higher sensitivity will be desirable since MRD can distinguish those who need intensive and potentially more toxic therapy from those who do not. The specific aims of this project are to (1) design and fabricate a device for enrichment of leukemia cells; (2) demonstrate the enrichment of leukemia cells in the device using aptamers with specific binding to acute lymphoblastic leukemia cells; and (3) validate the platform technology by analyzing leukemia cells in clinical samples and detect MRD. The significance of the research lies in the following aspects. First, the proposed research will lead to a platform for a rapid and efficient enrichment of acute leukemia cells. The platform will offer a measureable approach to determine if any additional chemo-therapy is needed; this will bring significant benefits to leukemia patients since unnecessary toxic therapy can be avoided. Second, the platform can be easily adapted for enrichment of rare circulating cells of other cancers. Isolation of these rare tumor cells could offer an opportunity for early-stage cancer screening and medical diagnostics. Third, the proposed research will advance the fields of cancer biology, biomedical engineering, and micro-nanotechnologies.