Article

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

ABSTRACT

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.

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