Multiplexed microimmunoassays for five critical compounds were developed using a digital versatile disk (DVD) as an analytical support and detecting technology. To this end, coating conjugates were adsorbed on the polycarbonate face of the disk; a pool of specific antibodies, gold labeled secondary antibodies, and silver amplification were addressed for developing the assays. The detection principle is based on the capture of attenuated analog signals with the disk drive that were proportional to optical density of the immunoreaction product. The multiplexed assay achieved detection limits (IC10) of 0.06, 0.25, 0.37, 0.16, and 0.10 microg/L, sensitivities of (IC50) 0.54, 1.54, 2.62, 2.02, and 5.9 microg/L, and dynamic ranges of 2 orders of magnitude for atrazine, chlorpyrifos, metolachlor, sulfathiazole, and tetracycline, respectively. The features of the methodology were verified by analyzing natural waters and compared with reference chromatographic methods, showing its potential for high-throughput multiplexed screening applications. Analytes of different chemical nature (pesticides and antibiotics) were directly quantified without sample treatment or preconcentration in a total time of 30 min with similar sensitivity and selectivity to the ELISA plate format using the same immunoreagents. The multianalyte capabilities of immunoassaying methods developed with digital disk and drive demonstrated the competitiveness to quantify targets that require different sample treatment and instrumentation by chromatographic methods.

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ElsevierElena Fito, SF.; Carrera, J.; Rodrigo, J. (2011). A systems biology approach to the evolution of plant-virus interactions. Current Opinion in Plant Biology. 14(4):372-377. doi:10.1016/j.pbi.2011.03.013. Omic approaches to the analysis of plant-virus interactions are becoming increasingly popular. These types of data, in combination with models of interaction networks, will aid in revealing not only host components that are important for the virus life cycle, but also general patterns about the way in which different viruses manipulate host regulation of gene expression for their own benefit and possible mechanisms by which viruses evade host defenses. Here, we review studies identifying host genes regulated by viruses and discuss how these genes integrate in host regulatory and interaction networks, with a particular focus on the physical properties of these networks. A systems biology approach to the evolution of plant-virus interactions The systems biology approachGenomic tools have allowed assessment of gene expression at a genome-wide scale, providing unprecedented views of the host-virus interaction. To make use of all of the information contained in these large data sets, however, it is necessary to use computational and mathematical tools to disentangle the interactions between the molecular components of both biological entities and to identify how these interactions determine the outcome of the infection [1,2••], which is known as the field of genomic systems biology (GSB). GSB is a top-down approach that takes advantage of the recent development of high-throughput experimental techniques for obtaining omic data, and constitutes the antithesis of the reductionist paradigm (with a bottom-up perspective) that has been dominating molecular biology. The GSB approach consists of cycling between the generation of experimental data and modeling by means of reverse-engineering techniques to propose testable hypotheses about biological systems, experimental validation of these hypotheses and quantification of the relevant model parameters, and then using the newly acquired quantitative description to refine the computational model and finally make predictions of the system behavior [3,4•].To complete its infectious cycle, a few components of a virus, including its nucleic acids and encoded proteins, must establish multiple and complex interactions not only among themselves [5,6•,7,8] but also with a myriad of components of the host cell [9,10•,11]. The outcome of all these interactions is that the plant controls the spread of viral infection or, alternatively, the virus overcomes the host defenses and establishes a productive infection that may or may not be associated with the development of symptoms. While the GSB approach is being extensively used in the analysis of animal virus interactions (e.g. hepatitis C, human immunodeficiency, yellow fever, influenza A and herpesviruses), plant virologyhas not yet benefitted to the same extent, and the most relevant studies in the field generally apply some tr...

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