A microfluidic dual capillary probe to collect messenger RNA from adherent cells and spheroids

Graduate School of Environmental Studies, Tohoku University, Aobe 6-6-11-604, Sendai 980-8579, Japan.
Analytical Biochemistry (Impact Factor: 2.22). 12/2008; 385(1):138-42. DOI: 10.1016/j.ab.2008.10.039
Source: PubMed


Collection of bioanalytes from single cells is still a challenging technology despite the recent progress in many integrated microfluidic devices. A microfluidic dual capillary probe was prepared from a theta (theta)-shaped glass capillary to analyze messenger RNA (mRNA) from adherent cells and spheroids. The cell lysis buffer solution was introduced from the injection aperture, and the cell-lysed solution from the aspiration aperture was collected for further mRNA analysis based on reverse transcription real-time PCR. The cell lysis buffer can be introduced at any targeted cells and never spilled out of the targeted area by using the microfluidic dual capillary probe because laminar flow was locally formed near the probe under the optimized injection/aspiration flow rates. This method realizes the sensitivity of mRNA at the single cell level and the identification of the cell types on the basis of the relative gene expression profiles.

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    • "Mathematical models were introduced for the quantitative analysis of the dynamics and stability of cellular status at the genome, transcriptome, proteome, and/or metabolome levels. This type of single-cell study showed that the mRNA [9] [10] [11] [12] [13] [14] [15] [16] [17] and protein expression [1] [2] [3] [4] [5] [6] [7] [8] levels show extreme fluctuation in not only undifferentiated but also all kinds of cells. "
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