The added value of micro-nanotextured surfaces integrated in microfluidics and lab-on-a-chip

In the last 20 years, micro- and nano-textured surfaces have been produced by means of various surface engineering processes, imparting enhanced properties, such as tunable wettability from superhydrophilicity to superhydrophobicity, tunable optical, and antifouling or antibacterial properties, to the substrates on which micro-nanotexturing has been imposed. While these properties have been readily explored in open substrate surfaces presented in numerous publications, their implementation in microfluidic and lab-on-a-chip devices is less frequent although increasingly important through the incorporation of such surfaces as microfluidic walls. In this review article, we will focus on microfluidic and lab-on-a-chip devices in which micro-nanotextured surfaces have been integrated as passive valves and means of liquid transport, sensitive sensors, enhanced bacteria capturing and lysing devices, only to mention a few of their enhanced functionalities. The added-value of the incorporated surfaces in the device performance will be presented and analyzed. The aim is to provide a systematic elucidation into the multifaceted advantages and enhanced functional capabilities of micro-nanotextured surfaces when integrated within microfluidic systems.