Evaluation of FTA cards as a laboratory and field sampling device for the detection of foot-and-mouth disease virus and serotyping by RT-PCR and real-time RT-PCR.

FMDV Laboratory, Research and Development Center, Indian Immunologicals Limited, Rakshapuram, Gachibowli, Hyderabad 500032, India.
Journal of Virological Methods (Impact Factor: 1.88). 09/2008; 151(2):311-6. DOI: 10.1016/j.jviromet.2008.05.020
Source: PubMed

ABSTRACT Foot-and-mouth disease virus (FMDV) samples transported to the laboratory from far and inaccessible areas for serodiagnosis pose a major problem in a tropical country like India, where there is maximum temperature fluctuation. Inadequate storage methods lead to spoilage of FMDV samples collected from clinically positive animals in the field. Such samples are declared as non-typeable by the typing laboratories with the consequent loss of valuable epidemiological data. The present study evaluated the usefulness of FTA Classic Cards for the collection, shipment, storage and identification of the FMDV genome by RT-PCR and real-time RT-PCR. The stability of the viral RNA, the absence of infectivity and ease of processing the sample for molecular methods make the FTA cards a useful option for transport of FMDV genome for identification and serotyping. The method can be used routinely for FMDV research as it is economical and the cards can be transported easily in envelopes by regular document transport methods. Live virus cannot be isolated from samples collected in FTA cards, which is a limitation. This property can be viewed as an advantage as it limits the risk of transmission of live virus.

  • [Show abstract] [Hide abstract]
    ABSTRACT: The genetic characterization of wild-type measles viruses plays an important role in the description of viral transmission pathways and the verification of measles elimination. The 450 nucleotides that encode the carboxyl-terminus of the nucleoprotein (N-450) are routinely sequenced for genotype analysis. The objectives of this study were to develop improved primers and controls for RT-PCR reactions used for genotyping of measles samples and to develop a method to provide a convenient, safe, and inexpensive means to distribute measles RNA for RT-PCR assays and practice panels. A newly designed, genetically defined synthetic RNA and RNA isolated from cells infected with currently circulating genotypes were used to compare the sensitivity of primer pairs in RT-PCR and nested PCR. FTA(®) cards loaded with lysates of measles infected cells were tested for their ability to preserve viral RNA and destroy virus infectivity. A new primer pair, MeV216/MeV214, was able to amplify N-450 from viruses representing 10 currently circulating genotypes and a genotype A vaccine strain and demonstrated 100-fold increased sensitivity compared to the previously used primer set. A nested PCR assay further increased the sensitivity of detection from patient samples. A synthetic positive control RNA was developed that produced PCR products that are distinguishable by size from PCR products amplified from clinical samples. FTA(®) cards completely inactivated measles virus and stabilized RNA for at least six months. These improved molecular tools will advance molecular characterization of circulating measles viruses globally and provide enhanced quality control measures.
    Journal of clinical virology: the official publication of the Pan American Society for Clinical Virology 06/2013; · 3.12 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Brucellosis is an infectious disease that causes significant economic losses in production systems and has serious implications for animal and public health, given its zoonotic nature. The purpose of this study was to detect Brucella spp. by real-time PCR associated with the FTA® Elute method in lesions observed during sanitary inspections in beef slaughter and processing facilities under Federal Inspection in the Brazilian states of Rondônia, Pará, Tocantins, Mato Grosso, Mato Grosso do Sul, Goiás, São Paulo and Rio Grande do Sul. Of a total of 276 samples, 78 (28.3%) tested positive and 198 (71.7%) negative for Brucella spp. The real-time PCR technique associated with the FTA® Elute method proved to be an important tool for the diagnosis, judgment about and disposal of carcasses and viscera of slaughtered animals.
    Journal of Microbiological Methods 06/2014; · 2.10 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This publication presents novel, normally-closed, bidirectional micropumps. Their main innovation is a fabrication process that combines traditional silicon micromachining with innovative, multifunctional polymer technologies.Therefore a flexible and robust wafer-level bonding technology, based on a laminable permanent dry-film photoresist from Ordyl SY300 Series is utilized. Moreover, using the photolithographic capabilities of Ordyl, 3D MEMS fluidic structures such as micro-channels or, in this study, the pump and valve chambers are simultaneously fabricated. To establish and integrate two flexible and particle tolerant normally-closed microvalves into the micropump, a commercially available photopatternable spin-on silicone (Dow Corning WL5150) is introduced into the manufacturing process. The definition of a reproducible mechanical pre-deformation (2.8μm) of the silicone material was obtained within the Ordyl wafer-bonding procedure. This combination of features yields the normally-closed character and results in an extremely small leakage-flow in the closed-state up to 500mbar of applied backpressure. Furthermore, the usage of a multilayer piezo-actuator technology demonstrates the ability of considerably decreasing the piezo driving voltage from formerly applied 360Vp–p (peak-to-peak) down to 30Vp–p.The designed micropumps work bidirectionally by simply applying a reversed actuation scheme. Due to the increased compression ratio of up to 0.512, the presented micropumps are self-priming and can pump water and air. Peak flowrates of 1.65ml×min−1 and a sustainable backpressure of 600mbar for water are measured in the pumping mode. In the normally-closed state, a leak-rate of 291nl×min−1 is measured under 500mbar of applied backpressure. The overall size of the micropump is 30.65mm×13.35mm×1mm. The combination of traditional silicon MEMS and silicone–polymer microfabrication technologies reduces the manufacturing costs and boosts the device performance. Possible applications of the micropumps are the field of microfluidics in general, and micro dosing for biological and chemical applications (e.g. drug delivery).
    Sensors and Actuators A Physical 07/2011; 168(1):213-222. · 1.94 Impact Factor