Structure Optimization of Polymerase Chain Reaction Devices Under High Flow Rate: A Numerical Study

Area of Science:

• Biotechnology
• Microfluidics
• Biomedical Engineering

Background:

• Microfluidic polymerase chain reaction (PCR) chips are crucial for biological and medical research.
• Current designs face limitations in reagent processing and thermal response at high flow rates.

Purpose of the Study:

• To design and evaluate novel serpentine microfluidic PCR chips with double-sided heaters.
• To optimize chip geometry for improved thermal performance and reduced flow resistance under high flow rates.

Main Methods:

• Numerical simulations were employed to analyze temperature, velocity, and pressure distributions.
• Three chip designs were compared: standard serpentine, unchamfered expansions, and chamfered expansions.
• Simulations were conducted at flow rates of 75, 125, and 175 μL/min.

Main Results:

• The chip with chamfered expansions (case 2) showed a 41% higher pressure drop at 175 μL/min compared to the standard chip (case 1).
• Case 2 exhibited significantly improved thermal performance, including extended constant-temperature zones and increased temperature gradients in expansion areas.
• The maximum temperature difference in case 2 decreased by 80%.

Conclusions:

• The microfluidic chip design with chamfered expansions offers the best balance between thermal performance and flow resistance.
• This optimized design is suitable for high-flow-rate PCR applications, advancing biological and medical research capabilities.