Rare cancer cell analyzer for whole blood applications: microcytometer cell counting and sorting subcircuits.

We demonstrate sorting of rare cancer cells from blood using a thin ribbon monolayer of cells within a credit-card sized, microfluidic laboratory-on-a-card ("lab card") structure. This enables higher cell throughput per minute thereby speeding up cell interrogation. In this approach, multiple cells are viewed and sorted, not individually, but as a whole cell row or section of the ribbon at a time. Gated selection of only the cell rows containing a tagged rare cell provides enrichment of the rare cell relative to background blood cells. We also designed the cell injector for laminar flow antibody labeling within 20s. The approach combines rapid laminar flow cell labeling with monolayer cell sorting thereby enabling rare cell target detection at sensitivity levels 1000 to 10,000 times that of existing flow cytometers. Using this method, total cell labeling and data acquisition time on card may be reduced to a few minutes compared to 30-60 min for standard flow methods.

Rare cancer cell analyzer for whole blood applications: automated nucleic acid purification in a microfluidic disposable card.

One current challenge facing point-of-care cancer detection is that existing methods make it difficult, time consuming and too costly to (1) collect relevant cell types directly from a patient sample, such as blood and (2) rapidly assay those cell types to determine the presence or absence of a particular type of cancer. We present a proof of principle method for an integrated, sample-to-result, point-of-care detection device that employs microfluidics technology, accepted assays, and a silica membrane for total RNA purification on a disposable, credit card sized laboratory-on-card ('lab card") device in which results are obtained in minutes. Both yield and quality of on-card purified total RNA, as determined by both LightCycler and standard reverse transcriptase amplification of G6PDH and BCR-ABL transcripts, were found to be better than or equal to accepted standard purification methods.