Modeling and validation of a molded polycarbonate continuous-flow polymerase chain reaction devic

Abstract

A continuous flow polymerase chain reaction (CFPCR) system was designed, fabricated from molded polycarbonate, and tested. Finite element modeling was used to simulate the thermal and microfluidic response of the system. The mold insert for the initial prototypes was fabricated using the Xray LIGA microfabrication process and device components produced by hot embossing polycarbonate.Commercial thin film heaters under PID control were used to supply the necessary heat flux to maintain the steady-state temperatures in the PCR.The simulated transient temperature response at start up was compared to the experimental response.The simulated steady state temperature profile along the channel generated by the finite element analysis was compared to the experimental temperature profile displayed by liquid crystals. Experimental and simulated results were within 5% of each other, validating the thermal design of the CFPCR device.

High fidelity, high yield production of microfluidic devices by hot embossing lithography: rheology and stiction

“…2 Many thermoplastic polymers have been investigated as candidate materials for such applications, including poly-(methyl methacrylate) (PMMA), poly(cyclic olefin) (PCO or COC), polycarbonate (PC), poly(tetrafluoroethylene) (PTFE), polystyrene (PS) and others (Table 1). [3][4][5] Polymer hot embossing is an attractive alternative for the replication of micro and sub-micro features in thermoplastic materials with dimensions from a few nanometres to several centimetres. 6,7 Motifs include vias, cruciform electrophoretic channels, mixing chambers, serpentine races and retention posts.…”

Rapid PCR in a continuous flow device

“…34 Numerical simulations of the thermal and microfluidic response of the system were used to predict system performance. 35,36 Several groups have reported detailed thermal analyses of micro-PCR devices using finite element methods. [36][37][38][39][40][41] Lin et al optimized a conventional glass-Si micro-reaction chamber and compared the FE results to a simple 1-D heating model.…”

“…35,36 Several groups have reported detailed thermal analyses of micro-PCR devices using finite element methods. [36][37][38][39][40][41] Lin et al optimized a conventional glass-Si micro-reaction chamber and compared the FE results to a simple 1-D heating model. 37 Continuous flow PCR devices made from polycarbonate, ceramic, and Si-glass were modeled in order to establish the uniformity of the constant temperature zones.…”

“…29 Recently, a unique spiral micro-channel with 20 loops (y1.6 m) was hot embossed into polycarbonate (PC) for rapid continuous flow PCR. [32][33][34][35][36] The feasibility of the system was demonstrated by conducting the reaction with a constant linear flow velocity (2 mm s…”

“…15 Alternatively, DNA amplification can be achieved in a microfluidic platform by moving a PCR mixture in a microchannel repetitively through different temperature zones using a continuous-flow (CF) format. [24][25][26][27][28][29][30][31][32][33][34][35][36] The CFPCR approach can be conducted at relatively high speeds since it is not necessary to heat and cool the amplification chamber repeatedly. 26 Kopp et al were able to produce a relatively short target fragment (176 bp) in a cycle time of 4.5 s by starting the PCR with a large number of templates (y10 8 copies of a 1 kbp PCR product) along with nested primer sets.…”