Laboratory on a chip

The current trend in analytical chemistry applied to evaluate food quality and safety leans toward user-friendly miniaturized instruments and laboratory-on-a-chip applications. The techniques applied to direct screening of colorants in a food matrix include chemical microscopy, a spatial representation of chemical information from complex aggregates inside tissue matrices, biosensor-based screening, and molec-ularly imprinted polymer-based methods that serve as chemical alternatives to the use of immunosensors. 

Kniss, R., Revolution of the drug discovery process using laboratory-on-a-chip technology, Am. Lab., 30(24), 40, 1998. 

Analytical chemistry in the new millennium will continue to develop greater degrees of sophistication. The use of automation, especially involving robots, for routine work will increase and the role of ever more powerful computers and software, such as intelligent expert systems, will be a dominant factor. Extreme miniaturisation of techniques (the analytical laboratory on a chip ) and sensors designed for specific tasks will make a big impact. Despite such advances, the importance of, and the need for, trained analytical chemists is set to continue into the foreseeable future and it is vital that universities and colleges play a full part in the provision of relevant courses of study. 

Naval Research Laboratory 4555 Overlook Avenue SW Washington, DC, 20375 Chemistry Division/6112 Ph 202.404.3337 (Greg E. Collins) Greg.collins nrl.navy.mil Optical Sciences Division/5611 Ph 202.767.9473 (Hedi Mattoussi) hedimat ccs.nrl.navy, mil www.nrl.navy.mil Laboratory on a chip for explosive detection, quantum dot-protein bioconjugates, biosensors, UAV radar, and much more in basic research. 

Blankenstein, G., Larsen, U.D., Modular concept of a laboratory on a chip for chemical and biochemical analysis. Biosens. Bioelectronics 1998, 13, 427 138. 

Yang, H., Chien, R.L., Sample stacking in laboratory-on-a-chip devices. J. Chromatogr. A 2001, 924, 155-163. 

The concept of a complete laboratory on a chip has evolved over the past several years. Miniaturization of laboratory operations to the chip scale promises to reduce analysis costs by lowering reagent consumption, by automating the... 

A broad range of developments, generally described as laboratory-on-a-chip technologies, have been described and are being explored in several laboratories.15 A variety of lab-on-a-chip combinations can be used to multiplex a variety of separations with multiple detectors. Techniques such as molecular imprinting offer considerable promise for reducing the cost of these devices while maintain-... 

Interesting results in the field of surface manipulation (Figure 7.4) can also be envisaged to arise from the arrangement of nanotubes, fullerenes, or tiny diamond particles on surfaces or from the direct addressing of certain positions on carbon structures. The analytical laboratory on a chip, nanotube-based catalysts, highly efficient fuel cells or a luminous display with low power consumption illustrate the enormous potential of carbon research. 

The characterization of the expressed constituent of a VCL is greatly facilitated by the availability of efficient analytical methods such as mass and NMR spectrometries, capillary electrophoresis, micro-HPLC, etc. These can be applied either to the isolated constituent or even directly to its complex with the target (for the use of mass spectrometry, see [10]). It is clear that the development of micro-methods and laboratory-on-a-chip [11] procedures will have a strong impact on the implementation of combinatorial chemistry approaches. 

With the miniaturization enabled by the use of nanostructures and laboratory-on-a-chip, detection or identification devices may easily fit onto small unattended airborne vehicles. A suspect cloud could be probed by flying the unattended airborne vehicle through it or collecting physical samples from the site. In the near term, there will be enough uncertainty in the identification such that a high-regret decision should be based on laboratory confirmation of the field measurement. The same miniaturization may enable small, low power, and easy-to-obscure unattended ground stations that could serve as remote site detection or identification stations. ... 

The incorporation of these new spectroscopies into a laboratory-on-a-chip will be essential for adequate selectivity.Considerable progress has been made toward the development of microfabricated sensor arrays, where each element in the array is capable of its own preselected detection event, but the technology is not sufficiently robust to place into field operation. ... 

Conceiving a new technology is only the first step. As an example, the concept of a laboratory-on-a-chip has been slowly evolving - in some ways more slowly than expected - over the past 10 years. The slow pace has been attributed to the lack of a driving application, meaning one with an undeniable payoff that would focus the necessary resources and innovation. Examples of driving applications and the necessary underlying capabilities are discussed here for CB countermeasures. 

Laboratory-on-a-chip systems use immittance and dielectric variables measured with microelectrodes. In flow sensors, cell properties are measured with microelectrodes, and cell characterization and cell separation are performed. Properties of protein molecules have, for many years, been determined by the established methods of electrophoresis. Electrophoresis is based on the electric charge of cells and proteins, and the driving force exerted by an electric field. AU sorts of liquid suspensions with cells or bacteria can be measured with bioimmittance or permittivity. Cell adherence and cell micromotion can be monitored with microelectrodes equipped with a thin surface coating. 

Hughes MP (2002) Strategies for dielectrophoretic separation in laboratory-on-a-chip systems. Electrophoresis 23 2569-2582... 

The community of microfluidics aims at building laboratories-on-a-chip. These tiny fluid microprocessors perform complex analysis and synthesis tasks relevant to chemistry or biology. The ability to reliably dispense and control small fluid volumes in the form of drops or bubbles in the charuiels of a microfluidic chip is important for microfluidic applications, because bubbles can enhance mixing and droplets can encapsulate... 

Microelectromechanical systems (MEMS) have the potential for creating miniature bench-top laboratories on a chip (Janssens-Maenhout and Nucifora 2007). Such miniaturized... 

One pump design with dimensions in centimeters is used to articulate the nose cone of a small missile system (Shin et al., in press). Another application is a pumping motor that can move small amounts of fluids for various laboratory (e.g., laboratory-on-a-chip) and biomedical applications. For example, the pump can be used as an embeddable drug-dehvery system. Coupled with appropriate sensors, this miniature (submillimeter) pump could someday replace a human... 

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