Fabrication and performance of monodisperse liquid crystal droplet-based microchips for the on-chip detection of bile acids

Development in liquid crystal microcapsules: fabrication, optimization and applications

“…Recently, a novel microfluidic device composed of monodisperse 5CB and PVA/SDS stabilizers has been developed for the on-chip detection of bile acids (Figure 3b). [114] In the digestive system, the bile acids act as the emulsifier, which can remove lipids from the fatty food interface and promote the formation of micelles, accelerate the uptake of fatty food by the intestinal mucosal cell. [115] As a result, in such a LC-surfactant system, the flowing of bile acids can remove the sodium dodecyl sulfate shell from the LC-Ms, and thus cause the collapse of microcapsules.…”

“…b) the continuously flowing bile acids can remove SDS from the surface of 5CB droplets, leading to the instability of 5CB droplets, which can be used for bile acids detection. [114] Reproduced with permission from Elsevier. c) the combination of lgG antigen changes the configuration of liquid crystals from radial to bipolar, which can be used for the detection of IgG.…”

Applications of Microfluidics in Liquid Crystal-Based Biosensors

“…Compared with stationary solid support in the static microarray, LC droplets in the dynamic microarray are captured individually in a trapping chamber surrounded by an aqueous environment [55,57]. The inlet size and the outlet size of the trapping chamber are larger and smaller than the droplet size, respectively.…”

“…It has been shown that the relative motion of LC droplets to the aqueous flow inside the microchannel would induce a flow inside the LC droplet, which can trigger the configuration change of LC droplets [102]. With sodium dodecyl sulfate (SDS) and PVA as the stabilizers, Han and coworkers prepared monodisperse LC droplets using flowfocusing microstructure and captured them into a bypass-channel microarray for realtime detection of bile acids [55]. They found that the defect point of radial LC droplets showed a shift from the center in an aqueous environment with a flow rate of 200 μL/h, while the defect point returned back after the flow rate lowered to 3 μL/h.…”

“…Various analytical techniques, such as electrochemical [48], chemiluminescence [49] and optical fibers [50], have been integrated with microfluidic structures to develop miniaturized analysis systems. In recent years, benefiting from the easy integration, highly efficient mass transfer, small sample consumption and portability, microfluidic techniques have been emerging as an efficient tool in the fabrication and integration of LC-based biosensing platforms, offering promising solutions for preparing LC-based biosensors with controlled properties [51][52][53][54][55][56][57]. However, as far as we know, no review is available to summarize different types of LC-based microfluidic biosensors.…”