Nano-fluidics and Microfluidics

Lab-on-a-chip device

                                      Figure 1; Display of the design of the lab-on-a-chip device Source: (Vig et al. 2011)

Diagnosis of the samples can occur in situ, where the models are produced, instead of being conveyed around the lab. The dissimilarities in fluid dynamics on a reduced balance mean that it’s easier to regulate the interaction and movement of samples (Didar, 2010). The practice reduces chemical wastage and makes reactions more proficient. However, the improvement of the lab-on-chip structure is challenged by the fabrication and design of the devices on the small gauge which is cost-effective and functional (Esch, et al., 2015). Currently, micro-technique, nanofabrication, and material performance advancement have enabled numerous lab-on-a-chip structures to be established and tested (Gupta et al. 2010).

Nano-fluidics and Microfluidics

Lab-on-chip involves various technological aspects, Nano-fluidics, and microfluidics. Microfluidics is described as the small quantity fluid flow manipulation within the micrometer range channels (Petralia, et al., 2013). Nano-fluidics, on the other hand, involves the individual macromolecules movements in a solution. The microfluidics discipline established as a result of increased accuracy in the analytic techniques like the capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC) (Petralia, et al., 2013). The diagnostic methodologies are capable of obtaining correct results from a lesser size of the sample. As the abilities of the methods progressed, they were tried and applied in the short process (Petralia et al. 2013).

Lab-on-chip with molecular biology

The commercialization and understanding of the microfluidics and Nano-fluidics are essential in the improvement of available lab-on-chip devices. Some construction techniques are accessible for the manufacture of Nano-fluidic equipment and making an interface of the devices with the microfluidic structures (Mirasoli, et al., 2014). The operation motivates the learning of Nano-fluidic instruments as models present in the microfluidic systems, for instance, detection and analysis of DNA or the study of pre-concentrate analytes (Vig et al. 2011). However, the use of an electric field through a Nano-fluidic scheme forms areas of depleted and enriched ion concentration; the effect is referred to as concentration polarization (CP) (Vig, et al., 2011). CP changes the electric and conductivity field in the adjacent microchannels due to magnitude control which then affects the sample transportation through the entire system. CP reduction and augmentation zones are capable of propagation through the fused microchannel-nanochannel equipment; this intensely affects the behavior of the whole system (Luka et al. 2015).  

Lab-on-chip with molecular biology

The Use of Nanotechnology

Some enhancements in the Nanotechnological field have been essential in the advancement of the lab-on-chip machinery. Particularly, lithography, which is applied in the creation of the Nano-scale features on semiconductor and metal exteriors has been modified to generate small, micro-scale valves, pumps and various appliances for controlling the flow from the polydimethylsiloxane (PDMS) (Ríos, et al., 2012). PDMS is a flexible and clear elastomer, which is suited for enabling visual assessments and quick prototyping in the microfluidic systems. Nano-sensors are said to be essential elements of several lab-on-chip systems (Petralia, et al., 2013). Sensors are established by the use of nanomaterials such as the carbon nanotubes; the gears can detect limited concentrations as low as a single molecule (Mirasoli et al. 2014). These appliances are extremely valuable in permitting a significant degree of methodical flexibility in the systems of lab-on-chip technologies without the buildup of the general dimension of the structure (Mirasoli, et al., 2014).

Application of Nanotechnology in the Improvement of Lab-on-a-Chip System

The present art state in the LOC technology offers a standard shift for the medical diagnostics. In the cases of sending test samples to the outside labs for investigation, the healthcare professionals can apply LOC appliances in testing the patients at the point-of-care centers (Gupta, et al., 2010). This will result in a reduction of the diagnostic period to the minute from days. The analytical speed is very significant in the medical scenarios that are time-dependent like detecting a viral impurity in an aged person who is immune-compromised or when locating a biohazard from an exposed individual (Esch, et al., 2015). By contracting a modernized chemistry workshop on a micro-sized LOC equipment, indicative examination in resource-poor or remote locations is made possible. LOC has compelling advantages to the medical field, however, designing and manufacturing the devices is difficult (Christodoulides et al.2007). LOC appliances usually consist of a compound linkage of chambers, channels and valves/pumps.

Bio-recognition agents that are physically/chemically attached to the instrument detection area bind with the targeted analyte in the media under a motion to initiate an optical/electoral signal transduction (Christodoulides, et al., 2007). These strategies for LOC bio-detection have produced promising outcomes, including the application of smaller sample and reagent volumes with high-throughput production resulting in quick turnaround times (Didar, 2010). However, the present shortcomings to LOC expertise comprise of the failure to perceive and enumerate low levels of concentration, multiplex inability, and complex bio-functionalization or fabrication protocols which are expensive and hard to replicate (Luka et al. 2015).

The Use of Nanotechnology

Lab-on-chip with cell biology

The incorporation of the Förster Resonance Energy Transfer (FRET) reduces the microchip scheme complexity through eliminating the nanostructured separation requirement, as well as eradicating the need for bio-detection regions immobilized in the system (Didar, 2010). Enzyme-substrate association, DNA hybridization, and antibody-antigen linkage occur rapidly in the solution (Luka, et al., 2015). The free/bound sample, slow, and diffusion-restricted kinetics washing and separating steps linked to the dissimilar bio-sensing are eliminated (Ríos, Zougagh, and Avila 2012). Notably, the application of the luminous semiconducting Quantum Dots (QDs) holds the essentiality to the FRET-based, opt fluidic bio-detection outline that has the capability of the sensitive, multiplexed bio-diagnostic analysis (Ríos, et al., 2012). The Nano-crystalline matter possesses assets that are suited for ocular bio-sensing comprising of the size-tunable photoluminescence (PL), enhanced sensitivity/avidity bio-molecular probes; high quantum produces and opposition to photo-bleaching. Coupling QDs with the glowing dye-labeled biological analyses leads to FRET radars that are superior to the standard sensors in various ways (Gupta, et al., 2010). The QD-illumination dye bio-conjugates detect an extensive variety of biomarker substances via the decrease and increase in the FRET efficiencies (Christodoulides, et al., 2007).

Applications of Nanotechnology

Life science and Medical applications that have been explored include sequencing of RNA or DNA, protein crystallization for the screening of conditions (Mirasoli, et al., 2014). The Rapid, bespoke productivity of radioactively-characterized substances for positron emission tomography (PET) techniques are also explored. In food safety, pathogen detection is a significant aspect (Didar, 2010). A variety of identification schemes have been created to attain accurate, fast and sensitive results. The Nano-material have been essential in the monitoring of chemical and biological contaminants present in food (Mirasoli, et al., 2014). Their unique electrical and optical possessions highly relay on the local surroundings thus making the Nano-materials useful for the development of sensors (Didar, and Tabrizian 2010 

Conclusion:

Future progressions in lab-on-a-chip knowledge always rely on molecular biology and microfluidics. Nanotechnology plays a vital role in combining the fields as technology advances. In spite of the difficulties associated with the commercialization and of this technology, sustainable examples of the appliances have begun to cover the present market. Therefore, in a few years’ time, lab-in-chip will increasingly become essential in various industrial fields particularly the chemical and medical companies (Vig et al. 2011).

Lab-on-chip (LOC) discusses the technologies that enable processes which usually entail laboratory analysis and synthesis of chemicals. The operations occur on a scale that is minimized within a handheld or portable device (Christodoulides, et al., 2007). LOC refers to the diminishment of analytical schemes that incorporate various laboratory procedures such as DNA sequencing and PCR progressions into a separate chip at a minimized scale (Christodoulides, et al., 2007). Downscaling the practice units offers the LOC systems with several benefits such as high parallelization, cost efficiency, ergonomy, low volume components, high expandability, high sensitivity and high analytic speed (Didar, and Tabrizian 2010).

References:

Christodoulides, N., Floriano, P.N., Miller, C.S., Ebersole, J.L., Mohanty, S., Dharshan, P., Griffin, M., Lennart, A., Ballard, K.L.M., KING, C.P. and Langub, M.C., 2007. Lab?on?a?chip methods for point?of?care measurements of salivary biomarkers of periodontitis. Annals of the New York Academy of Sciences, 1098(1), pp.411-428.

Didar, T.F., and Tabrizian, M., 2010. Adhesion based detection, sorting and enrichment of cells in microfluidic Lab-on-Chip devices. Lab on a Chip, 10(22), pp.3043-3053.

Gupta, K., Kim, D.H., Ellison, D., Smith, C., Kundu, A., Tuan, J., Suh, K.Y. and Levchenko, A., 2010. Lab-on-a-chip devices as an emerging platform for stem cell biology. Lab on a Chip, 10(16), pp.2019-2031.

Esch, E.W., Bahinski, A. and Huh, D., 2015. Organs-on-chips at the frontiers of drug discovery. Nature reviews Drug discovery, 14(4), p.248.

Mirasoli, M., Guardigli, M., Michelini, E. and Roda, A., 2014. Recent advancements in chemical luminescence-based lab-on-chip and microfluidic platforms for bioanalysis. Journal of pharmaceutical and biomedical analysis, 87, pp.36-52.

Luka, G., Ahmadi, A., Najjaran, H., Alocilja, E., DeRosa, M., Wolthers, K., Malki, A., Aziz, H., Althani, A. and Hoorfar, M., 2015. Microfluidics integrated biosensors: a leading technology towards lab-on-a-chip and sensing applications. Sensors, 15(12), pp.30011-30031.

Petralia, S., Verardo, R., Klaric, E., Cavallaro, S., Alessi, E. and Schneider, C., 2013. In-Check system: A highly integrated silicon Lab-on-Chip for sample preparation, PCR amplification and microarray detection of nucleic acids directly from biological samples. Sensors and Actuators B: Chemical, 187, pp.99-105.

Ríos, Á., Zougagh, M. and Avila, M., 2012. Miniaturization through lab-on-a-chip: Utopia or reality for routine laboratories? A review. Analytica Chimica Acta, 740, pp.1-11.

Vig, A.L., Mäkelä, T., Majander, P., Lambertini, V., Ahopelto, J. and Kristensen, A., 2011. Roll-to-roll fabricated lab-on-a-chip devices. Journal of Micromechanics and Microengineering, 21(3), p.035006.