Human pluripotent stem cells (hPSCs) are thought to be a promising cell-source solution for regenerative medicine due to their indefinite proliferative potential and ability to differentiate to functional somatic cells. However, issues remain with regard to achieving reproducible differentiation of cells with the required functionality for realizing human transplantation therapies and with regard to reducing the potential for bacterial or fungal contamination. To meet these needs, we have developed a closed-channel culture device and corresponding control system. Uniformly-sized spheroidal hPSCs aggregates were formed inside wells within a closed-channel and maintained continuously throughout the culture process. Functional islet-like endocrine cell aggregates were reproducibly induced following a 30-day differentiation protocol. Our system shows an easily scalable, novel method for inducing PSC differentiation with both purity and functionality.

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Mutual diffusion coefficients for aqueous solutions of 3-aminopropanoic acid (β-alanine), 4-aminobutanoic acid (γ-aminobutyric acid), 5aminopentanoic acid, 6-aminohexanoic acid, and 7-aminoheptanoic acid at infinitesimal concentration were measured at atmospheric pressure and temperatures from (298.2 to 333.2) K using the Taylor dispersion method. The results were compared with those of the structural isomers measured in our previous studies to examine the effect of position of amino and carboxylic acid groups on the values of diffusion coefficients. The diffusion coefficients of all amino acid isomers were almost the same, indicating that the diffusion coefficients of amino acids measured in our studies were mostly determined by the molar mass and the increase in the distance between amino and carboxylic acid groups was not an important factor. The temperature dependences of the diffusion coefficients were well-correlated with viscosity of water, η, as D 12 /T = αη β where D 12 is the diffusion coefficient at infinitesimal concentration of solute, T is the absolute temperature, and α and β are the fitting parameters.

Human induced pluripotent stem cells (hiPSCs) can be differentiated at high efficiency into cells of a targeting type but the resulting cell population has to be of high purity for clinical therapies to avoid teratomas. Herein, we report a microfluidic device with integrated and surface functionalised fishnet-like structures for specific cell capture. With the help of a flow derivation surface pattern, cells in solution are forced to cross the fishnet-like structure, resulting in high efficiency and selective retention of a chosen cell population. A suspension of hiPSCs and hiPSC-derived cardiomyocytes were used for device function validation. We found that a hiPSC capture rate over 80% can be achieved along with a remarkable increase in the CM population rate in the recovered suspension without affecting cell viability.

Background: Blood sampling by finger puncture is convenient, but the need for centrifugation and the problem of hemolysis remain, as does instability when samples must be shipped for analysis. We aimed to develop a blood-sampling device that provided high yields of serum with limited hemolysis and enabled preservation of serum components for at least 7 days at room temperature. Methods: For separation of blood cells, we devised a grooved, asymmetric, polysulfonate membrane impregnated with sucrose. We evaluated hemoglobin (Hb) concentrations in the serum, assay values for 15 frequently measured serum components (including glucose), and the stability of analytes in the device. Results: In sera from the new device, the Hb concentration was ≤0.43 mg/L. Recovered serum contained 65.0% ± 4.2% (mean ± SD; n = 41) of each of the serum components obtained by centrifugation. Serum components were stable in the device for 10 days at room temperature (25 °C). Conclusions: The newly developed device allows recovery of 60% of serum components from microvolumes of blood by finger puncture with neither degradation of analytes at room temperature nor hemolysis.