RESUMO
Rapid diagnostic tests (RDTs) can serve as good alternatives to standard serological assays for hepatitis C virus (HCV) detection in limited resource settings. Aim of this study was to evaluate performance of three Indian manufactured RDTs with chemiluminescent microparticle immunoassay (CLIA) for screening of HCV infection with further evaluation using HCV RNA. Serum samples tested for anti-HCV by CLIA (Architect i1000SR, Abbott Diagnostics, IL, USA) were retrieved from - 80 °C and retested for anti-HCV by three RDTs: Alere Trueline (SD Bioline; Haryana, India) (RDT 1), Benesphera HCV Rapid card test (Avantor Performance Materials India Limited; Uttarakhand, India) (RDT 2), AccuTest HCV (Accurex Biomedical Pvt. Ltd.; Mumbai, India) (RDT 3). HCV RNA results were obtained from hospital information system and anti-HCV reactive but RNA negative cases without treatment were considered as either 'false positives' or 'spontaneous clearance of HCV RNA'. Among 86 samples, 75 (87.2%), 49 (57%), 58 (67.4%) and 51 (59.3%) were reactive by CLIA, RDT1, RDT2 and RDT3, respectively. Taking CLIA as reference standard, RDT 1, 2 and 3 demonstrated sensitivity of 65.30%, 77.33% and 68% respectively. Specificity of all three RDTs was 100% with sensitivity of 97.6-100% above signal/cut-off ratio (S/Co) of 6 by CLIA and 88-100% in all HCV RNA positive cases. Sensitivity of RDTs increased from 65.30-77.33 to 72-82.4% when RNA negative/anti-HCV reactive results were considered as non-reactive. The three RDTs have acceptable sensitivity and specificity in anti-HCV detection especially in RNA positive patients that would require treatment for HCV.
RESUMO
Potential applications of thin film metamaterials are diverse and their realization to offer miniaturized waveguides, antennas and shielding patterns are on anvil. These artificially engineered structures can produce astonishing electromagnetic responses because of their constituents being engineered at much smaller dimensions than the wavelength of the incident electromagnetic wave, hence behaving as artificial materials. Such micro-nano dimensions of thin film metamaterial structures can be customized for various applications due to their exclusive responses to not only electromagnetic, but also to acoustic and thermal waves that surpass the natural materials' properties. In this paper, the recent major advancements in the emerging fields of diagnostics (sensors) and therapeutics involving thin film metamaterials have been reviewed and underlined; discussing their edge over conventional counterpart techniques; concentrating on their design considerations and feasible ways of achieving them. Challenges faced in sensitivity, precision, accuracy and factors that interfere with the degree of performance of the sensors are also dealt with, herein.
