In one aspect, a method of cell processing is disclosed, which includes disposing a plurality of cells on a substrate across which a plurality of projections are distributed and an electrically conductive layer at least partially coating said projections, exposing the cells to a cargo to be internalized by the cells, irradiating the substrate surface (and in particular the projections) with one or more laser pulses having a pulse width in a range of about 1 ns to about 1000 ns so as to facilitate uptake of the cargo by at least a portion of the cells (e.g., the cells positioned in the vicinity of the projections (e.g., within hundreds of nanometer (such as less than 100 nm) of the projections)). In some embodiments, the laser pulses have a pulse width in a range of about 10 ns to about 500 ns, e.g., in a range of about 5 ns to about 50 ns.