Nano- and microscale manipulation of biological particles by laser-guided direct writing

Tissue engineering has shown great potential for solving health problems through replacing or repairing malfunctioning tissue with functional constructs of living cells and associated molecules. To realize this potential, complicated cell-cell interactions both in the macro scale and micro scale need to be understood. Nanotechnology is now playing an important role in attaining this understanding. One of the emerging techniques in this field is laser-guided direct writing (LGDW), which involves the use of optical forces generated by a weakly focused laser beam to propel suspended, nano/micro scale particles along the beam axis towards a target surface. It has been used in our lab to guide 100nm colloidal gold particles and to directly fabricate two-dimensional patterns of cells. LGDW can potentially be used to create arbitrary three-dimensional patterns of multiple cell types.