Hydrodynamic trap array
Hydrodynamic Trap Array. The array includes a serpentine bypassing channel including a plurality of trapping pockets disposed therein, the trapping pockets including a ramp entry portion to decrease flow velocity orthogonal to the trapping pocket to increase trapping efficiency. The relative fluid resistances of the trapping pockets and the serpentine bypassing channel are selected such that a slight majority of the flow is diverted to one of the trapping pockets. A pair of microfluidic bypass channels flank the array of traps allowing independent control of upstream and downstream pressures on each side of the array, thereby decoupling flow magnitude in the bypass channels from flow across the trapping pockets.
1. Array of microfluidic hydrodynamic traps comprising:
a serpentine bypassing channel including a plurality of trapping pockets disposed therein, each of the trapping pockets including a ramp entry portion to decrease flow velocity orthogonal to the trapping pocket to increase trapping efficiency and each of the trapping pockets including an exit portion in fluid communication with an adjacent serpentine bypassing channel and wherein the relative fluid resistances through the trapping pockets and the serpentine bypassing channel are such that a majority of the flow is diverted to one of the trapping pockets; and
a pair of microfluidic bypass channels flanking the array of traps and in fluid communication therewith through a branch substantially orthogonal to the bypass channels allowing independent control of upstream and downstream pressures on each side of the array, thereby decoupling flow magnitude in the bypass channels from flow across the trapping pockets.
2. The array of claim 1 further including a PEG layer on surfaces of the serpentine bypassing channels.
3. The array of claim 1 wherein surfaces of the serpentine bypassing channel are native silicon.