Cell fractionation on pH-responsive chitosan surface.

The purpose of this study is to demonstrate pH-responsive chitosan is able to be used for cell fractionation under precise adjustment of medium pH. Cells were first seeded to attach on chitosan surface at medium pH 7.20 for 24 h. After raising medium pH to 7.65 for 1 h, cells with elongated morphology possessed rapider detachment rate and cells with round shape detached at a lesser rate. Therefore, successful cell separation has been achieved by choosing appropriate cell combination with different detachment rates without additional antibody or enzyme treatment and extensive washing steps. Furthermore, the method also could be applied to specific manipulation of viable cell populations from tissue specimen. Most importantly and interestingly, the efficiency of cell fractionation of our system could be theoretically predicted according to the individual cell detachment rate on pH-responsive chitosan surface, without considering the presence of heterotypic cells.