Micro Total Analysis Systems For Cell Biology and Biochemical Assays

Department of Chemistry, University of North Carolina, Chapel Hill, North Carolina 27599, United States.
Analytical Chemistry (Impact Factor: 5.64). 10/2011; 84(2):516-40. DOI: 10.1021/ac202611x
Source: PubMed


Novel applications of micro total analysis systems (μTAS) are addressing fundamental biological questions, fabricating new biomedical reagents, and developing cell and biochemical assays. These efforts impact progress in all areas of μTAS from materials to fluidic handling as well as detection and external control systems. Three areas show the greatest current and potential impact on the biomedical sciences: improvements in device fabrication and operation, development of enabling technologies, and advancements at the interface with biology (Figure 1). The range of materials from which devices can be fabricated has expanded considerably and now includes paper, fabric and thread, and a multitude of polymers as well as more conventional materials. Thus device substrates and component materials suitable for nearly all biological applications are readily available. Devices are also becoming increasingly integrated with advancements in sampling handling and preparation, a key and first step in any biological analysis. Another growing area focuses on modular components that can be mixed and matched on-demand and applied to many different assays, so-called programmable microfluidics. This development should enhance the rate at which new bioassays are generated as well as customize existing experimental protocols. A second area of rapid advancement has been the development new technologies that enable assays that cannot be efficiently performed by any method except μTAS. Novel analyses of single cells are enabled due to effective manipulation of picoliter-scale volumes. Synthesis and screening of large-scale libraries has become increasingly feasible due to the fast processing speeds and combinatorial mixing of reagents provided by lab-on-chip systems. Increased automation within a completely contained system has now begun to provide some of the first true μTAS diagnostic devices for clinical medicine. The third area in which μTAS has begun to yield high dividends is the interfacing of living entities with microdevices to create biological communities including tissues and organs on-chip. Control of cell placement in multiple dimensions has produced biological systems midway between the conventional tissue-culture dish and an intact animal. Thus the complexities of living constructs can be recreated in a controlled experimental environment permitting groundbreaking biological questions to be addressed. Application of μTAS in all of these areas continues to be highly interdisciplinary, utilizing techniques and strategies from almost every scientific field. This multidisciplinary focus insures continued relevance to the biological community as well as a bright future.

  • Source
    • "Hydrodynamic focusing of particles in straight microchannels, for its efficiency, simplicity and potential high-throughput particle separation and analysis, is developing as one of the most utilized techniques in microfluidics[1]. Considerable attentions have been attracted in the last decades for the wide scientific applications including life science and chemical/biological analysis23456. Perception of regularities in hydrodynamic focusing is therefore of great importance for designing and fabricating fully functional microfluidic chips. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Hydrodynamic focusing of particles is numerically studied by the immersed boundary – lattice Boltzmann method. Particle focusing entropy is proposed to quantitatively characterize processing performance and final results of hydrodynamic focusing. Simulations of hydrodynamic focusing in several straight microchannels are carried out to evaluate versatility of the focusing entropy. Time evolutions of focusing entropies and particle trajectories are analyzed contrastively. The results demonstrate that the focusing entropy is an effective scale to measure particles ordering degree and hydrodynamic focusing performance. Higher ordering degree determines lower focusing entropy, which indicates better focusing performance. Channel cross section, particle rigidness and channel Reynolds number are three major factors influencing focusing dynamics and final results. Rectangular microchannel is more advantageous than circular and square ones in hydrodynamic focusing. Particles of different rigidness in rectangular microchannel can be separated significantly with the flow mediation. Increasing channel Reynolds numbers can lead to higher efficiency and better focusing performance.
    Full-text · Article · Mar 2016 · International Journal of Heat and Mass Transfer
  • Source
    • "In the future, such database-oriented lab-on-chip devices might grow into a new branch in the microsystems research field. Compared with the study for MicroTAS systems [29], which try to make the microdevices more and more complex [30], the database-oriented lab-on-chips will be simpler and simpler with the essential precondition of qualified detection capability, so as to reduce the cost of data acquisition in the medical investigation. This study built a model for other database-oriented lab-on-a-chip devices. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Mood disorders are common mental diseases, but physiological diagnostic methods are still lacking. Since much evidence has implied a relationship between mood disorders and the protein composition of blood sera, it is conceivable to develop a serological criterion for assisting diagnosis of mood disorders, based on a correlative database with enough capacity and high quality. In this pilot study, a low-cost microfluidic microarray device for quantifying at most 384 serological biomarkers at the same time was designed for the data acquisition of the serological study. The 1,536-chamber microfluidic device was modeled on a 1,536-well microtiter plate in order to employ a common microplate reader as the detection module for measuring the chemiluminescent immunoassay tests on the chips. The microfluidic microarrays were rapidly fabricated on polymethylmethacrylate slides using carbon dioxide laser ablation, followed by effective surface treatment processing. Sixteen types of different capture antibodies were immobilized on the chips to test the corresponding hormones and cytokines. The preliminary tests indicated that the signal-to-noise ratio and the limit of detection of microfluidic microarrays have reached the level of standard ELISA tests, whereas the operation time of microfluidic microarrays was sharply reduced.
    Full-text · Article · Nov 2013 · Sensors
  • [Show abstract] [Hide abstract]
    ABSTRACT: This paper reports the fabrication and characterization of a prototype microfluidic device that can act as a periodic beam steerer. The prototype is formed by a simple T-junction followed by a serpentine channel that allows generation of a periodical segmented flow of air and water bubbles. If light hits the channel wall with a suitable angle, it can be either transmitted or reflected by the segmented flow, giving rise to an alternating beam steerer. The duty cycle, switching frequency, and overall stability and reproducibility of this prototype system are presented and discussed.
    No preview · Article · Jan 2013 · Microfluidics and Nanofluidics
Show more