Enhancing Biotechnological Applications Using an Optimized Semiconductor Refrigeration Device

Semiconductor refrigeration plates (also known as thermoelectric coolers, TECs) are increasingly recognized as one of the most promising refrigeration technologies due to their compact size and rapid cooling capabilities. However, the full utilization of the temperature difference on both sides of the TEC to maximize performance has been limited. This study developed a novel semiconductor refrigeration device integrated with microchannels. This design achieves synergistic thermal management, enabling precise and independent temperature control on both the cold (4 °C) and hot (42 °C) sides. Further optimization of the device enhanced the effective utilization of the temperature gradient between the two sides. Using this device, the transformation of <i>Escherichia coli</i> was completed in just 2 min, achieving a transformation efficiency of 11.9 × 10⁸ CFU/μg DNA, which was 1.5 times higher than that of traditional heat shock methods. The study also revealed that the device could facilitate the intracellular delivery of small molecules like trehalose, achieving 84% cell viability in cryopreservation, compared to approximately 4% for the untreated control, and comparable to that of conventional DMSO-based methods (90%). Notably, this approach eliminates complex washing steps for organic solvent removal. With its simple structure, stability and portability, this dual-temperature platform holds considerable potential for effective temperature control and intracellular delivery in biotechnological applications.