Centrifuge-based cell encapsulation in hydrogel microbeads using sub-microliter sample solution

This paper describes a simple, rapid, and inexpensive method for cell encapsulation that uses a small amount (sub-microliter-scale) of cell-suspended pre-gel solution. This method requires only a glass capillary, an acrylic holder, and a tabletop centrifuge, and achieves cell encapsulation in calcium alginate microbeads using cell-suspended sub-microliter-volume pre-gel solution in 20 s. The method also ensures high cell encapsulation efficiency, with a sample loss of as low as several tens of nanoliters. Formation of calcium alginate hydrogel microbeads encapsulating Jurkat cells by the proposed method is experimentally demonstrated using 0.5 μL of cell-suspended sodium alginate solution. Our proposed method is expected to be a promising approach for encapsulating rare and precious samples by non-specialists of microfluidics working in the fields of point-of-care and tailor-made medicine.