In the industrial sector, in vitro diagnostics (IVD) is the leading application area for microfluidics, offering significant financial returns. The growing demand for microfluidic chips is fueled by demographic trends, particularly the aging population. Governmental support for advancing microfluidics has intensified, particularly in the wake of the pandemic. The key challenges for microfluidic chip technology moving forward are reducing manufacturing costs and achieving scalability while maintaining product consistency and minimizing variability.
Modern technology trends emphasize miniaturization, integration, and intelligence. Microelectromechanical systems (MEMS) have been crucial in this evolution, transitioning from large electronic systems to compact integrated circuits and handheld devices like smartphones. Similarly, microfluidic chips, often known as Lab-on-a-Chip technology, represent a major advancement in fluid manipulation at micro- and nanoscales. These chips consolidate essential laboratory functions—such as sample preparation, reaction, separation, and detection—into a compact platform, typically a few square centimeters in size. Their key advantage is the ability to integrate and scale various technologies within a controlled microenvironment.
Early microfluidic chips, derived from MEMS technology, were fabricated on substrates such as silicon, metals, polymers, glass, and quartz. These processes created microstructures like fluid channels, reaction chambers, filters, and sensors, with dimensions ranging from micrometers to sub-millimeters. These microstructures enabled automated biological laboratory procedures, including extraction, amplification, labeling, separation, and analysis.
In the early 1990s, A. Manz and colleagues demonstrated the potential of microfluidic chips in analytical chemistry by achieving electrophoretic separation on chips—a technique previously limited to capillaries. Research into microfluidic chips expanded globally, driven by the U.S. Department of Defense's demand for portable biochemical self-test equipment. Throughout the 1990s, microfluidic chips, also known as "Micro Total Analysis Systems" (u-TAS), were primarily used for analytical chemistry and found applications in fields such as biomedical diagnostics, food safety, environmental monitoring, forensics, military, and aerospace sciences.
Key advancements in microfluidic chip technology include G. Whitesides et al.'s 2000 work on PDMS soft lithography and S. Quake et al.'s 2002 research on "large-scale integration of microfluidic chips," which introduced microvalve and micropump controls. These pioneering studies extended the applications of microfluidic chips beyond traditional analytical systems, opening new possibilities in scientific and industrial fields. Today, microfluidic chips enable combinatorial chemical reactions, droplet techniques, drug synthesis, high-throughput screening, and large-scale production of nanoparticles and microspheres, effectively creating a "chemical plant or pharmaceutical lab on a chip."