Accurate temperature regulation is essential in microfluidic apparatus, particularly for procedures such as polymerase chain reaction (PCR), cellular analysis, and chemical reactions that rely on stable thermal conditions. However, achieving temperature uniformity at the microscale remains challenging due to rapid heat dissipation, small thermal mass, and intricate flow–heat interactions. This work reviews contemporary methodologies to enhance thermal control in microfluidic systems, including proportional–integral–derivative (PID) and fuzzy PID controllers, liquid metal-based sensing, thermoelectric cooling (TECs), and evaporation or integrated heating elements for precise thermal output management. Emerging fabrication technologies, such as additive manufacturing, enable the direct integration of heating elements and sensors within microchips, improving thermal efficiency and device compactness. Advanced materials, including carbon nanotubes infused with gallium and temperature-sensitive quantum dots, offer innovative, non-contact thermal monitoring capabilities. Furthermore, artificial intelligence-driven feedback systems present opportunities for adaptive, real-time thermal optimization. By consolidating these strategies, this review highlights pathways to develop more dependable, efficient, and application-ready microfluidic devices, with implications for diagnostics, research, and other practical uses.

Quantum dots with sizes between 1 and 100 nm possess unique optical and electronic properties, making them valuable in energy, bioimaging, and optoelectronics fields. While traditional synthesis methods offer control over QD properties, they face challenges in scalability and reproducibility. Integrating microfluidics addresses these issues, providing precise control and high-throughput capabilities. This review highlights the transition from PDMS-based devices to additive-manufactured microfluidics, emphasizing their ability to overcome limitations in traditional methods. These advancements smooth the way for scalable, cost-effective, and sustainable QD production with enhanced application potential.

Microdroplet-based fluidic systems have the advantages of small size, short diffusion time, and no cross-contamination; consequently, droplets often provide a fast and precise reaction environment as well as an analytical environment for individual molecules. In order to handle diverse reactions, we developed a method to create organic single-micron droplets (S-MDs) smaller than 5 μm in diameter dispersed in silicone oil without surfactant. The S-MD generation microflow device consists of a mother droplet (MoD) generator and a tapered separation channel featuring multiple side channels. The tapered channel enhanced the shear forces to form tails from the MoDs, causing them to break up. Surface treatment with the fluoropolymer CYTOP protected PDMS fluid devices from organic fluids. The tailing separation of methanol droplets was accomplished without the use of surfactants. The generation of tiny organic droplets may offer new insights into chemical separation and help study the scaling effects of various chemical reactions.

Our ‘trap-and-harvest’ device integrates in situ solid formation in trapped droplets with transfer to a physically accessible chamber, facilitating the direct harvesting of solid precipitates from the microfluidic device.

Continuously rotating a single microdroplet within a circular loop channel keeps the droplet in motion while holding it within a fixed field of view. Existing approaches to droplet rotation, however, typically rely on multi-layer devices equipped with pneumatic control valves, which complicate both fabrication and operation. In this study, we present a method, free of embedded pneumatic valves, in which a single droplet is rotated in a circular loop microchannel by applying three pressure waveforms, analogous to the driving currents of a three-phase synchronous motor, to three radially arranged control channels. The operating principle is formulated using this motor analogy, and an equation of motion is derived that explicitly accounts for the time delays arising from the pressure pumps and the feedback loop. Computational fluid dynamics simulations and experiments consistently show that the measured optimal lead angle closely matches the theoretical prediction of 90° across a range of system parameters, including tubing length. The proposed framework simplifies the integration of loop-based droplet manipulation into existing lab-on-a-chip devices and provides a practical design guide for controlling such systems.

Laminar co-flow in microchannels typically results in stratified streams with diffusion-limited mixing. This work presents an additively manufactured microfluidic platform that integrates a pulse tank and a transverse injection nozzle into an otherwise straight channel, enabling pulse-driven mixing and droplet generation using air-pressure actuation alone. In Device A, transverse pulsed injection disrupted the stratified interface and significantly enhanced mixing compared with the no-pulse case, as confirmed by an entropy-based mixing index. In Device B, pulsed injection into a continuous oil phase enabled stable droplet-on-demand generation with pressure-tunable droplet diameter in a straight circular channel. The devices operated in a laminar regime, with representative Reynolds, Péclet, and capillary numbers confirming diffusion-limited baseline mixing and stable dripping-type droplet formation. The results demonstrate that pulse-driven injections in a simple, additively manufactured geometry provide an effective, low-complexity approach to mixing enhancement and droplet generation without external fields or complex channel designs.