Professional Education


  • Postdoc, Hong Kong University of Science and Technology, Chemistry (2011)
  • Doctor of Philosophy, Tsinghua University (2008)

Stanford Advisors


Journal Articles


  • Sorting Inactivated Cells Using Cell-Imprinted Polymer Thin Films ACS NANO Ren, K., Banaei, N., Zare, R. N. 2013; 7 (7): 6031-6036

    Abstract

    Previous work showed that cell imprinting in a polydimethylsiloxane (PDMS) film produced artificial receptors to cells by template-assisted rearrangement of functional groups on the surface of the polymer thin film which facilitated cell capture in the polymer surface indentations by size, shape, and most importantly chemical recognition. We report here that inactivation of cells by treatment with formaldehyde (4%), or glutaraldehyde (2%), or a combination of the two leads to markedly improved capture selectivity (a factor of 3) when cells to be analyzed are inactivated in the same manner. The enhanced capture efficiency compared to living cells results from two factors: (1) rigidification of the cell surface through crosslinking of amine groups by the aldehyde; and (2) elimination of chemicals excreted from living cells which interfere with the fidelity of the cell imprinting process. Moreover, cell inactivation has the advantage of removing biohazard risks associated with working with virulent bacteria. These results are demonstrated using different strains of mycobacterium tuberculosis.

    View details for DOI 10.1021/nn401768s

    View details for Web of Science ID 000322417400045

    View details for PubMedID 23725546

  • Chemical Recognition in Cell-Imprinted Polymers ACS NANO Ren, K., Zare, R. N. 2012; 6 (5): 4314-4318

    Abstract

    A glass slide covered with bacteria is pressed into another glass slide coated with partially cured polydimethylsiloxane (PDMS). The PDMS is hardened and the cells are removed to create a textured surface whose indentations preferentially capture the same type of bacteria when a mixture of bacteria is flowed over it. Overcoating the cell-imprinted PDMS with methylsilane groups causes the resulting surface to lose much of its ability to preferentially capture the imprinted bacteria, although the shapes of the imprints, measured by atomic force field microscopy, are shown to be hardly affected. We interpret this behavior as strong evidence that chemical recognition plays a dominant role in cell sorting with cell-imprinted PDMS polymer films.

    View details for DOI 10.1021/nn300901z

    View details for Web of Science ID 000304231700073

    View details for PubMedID 22468923

  • Surface-imprinted polymers in microfluidic devices SCIENCE CHINA-CHEMISTRY Schirhagl Romana, R., Ren Kangning, K. N., Zare Richard, N. 2012; 55 (4): 469-483