Piezoelectric Immunosensor for the Determination of Immunoglobulin G

Abstract

Immunoglobulin G (IgG) is an immunochemical marker with broad importance because of its employment in various diagnoses like chronic infections, some inflammatory diseases, hyperimmunization, multiple myeloma, leukemia or lymphoma. The IgG level in blood or blood plasma is typically measured by an instrumental method from which Enzyme-Linked Immuno-Sorbent Assay (ELISA) is the most important one. Simple method suitable for field or homecare is however missing. This paper is devoted to the construction of immunochemical biosensor based on Quartz Crystal Microbalance (QCM) platform for a simple determination of IgG. A polyclonal antibody specific to IgG was covalently attached to electrode and standard IgG was assayed and the resulted data were validated to ELISA method. The immunosenor was found to be a reliable platform and IgG was determined with limit of detection 9.7 µg/ml and the achieved calibration fully correlated with ELISA which is perceptible from coefficient of determination r 2 = 0.976. The immunosensor exerted long term stability and it was usable after at least two months. In a conclusion, the immunosensor appears to be a reliable tool for a fast, label-free determination of IgG without any necessity to have expensive equipment or skills.

Rapid Detection of Bifidobacterium bifidum in Feces Sample by Highly Sensitive Quartz Crystal Microbalance Immunosensor

“…No clear linear portions of the concentrations of B. bifidum can be observed using mouse monoclonal antibody-AuNPs conjugation as detection layer. The results recorded in this study are very competitive with previous reports (Fung and Wong, 2001;Guo et al, 2012;Skládal, 2016;Della Ventura et al, 2017;Wang R. et al, 2017;Gao et al, 2018;Pohanka, 2018aPohanka, ,b, 2019. Table 1 showed the sensing performance comparison.…”

Progress in Biosensors for the Point-of-Care Diagnosis of COVID-19

“…Antibodies can be easily detected by a piezoelectric biosensor. This type of assay was described for the diagnosis of various pathological states with quartz crystal microbalance as the sensor platform [ 94 , 95 , 96 , 97 ]. This type of biosensor remains rare for development of new point-of-care tests for the diagnosis, but they are quite convenient for the purpose and interest for piezoelectric platform can grow in the future.…”

COVID-19 molecular level laboratory diagnoses

“…Concentration of immunoglobulins is quite high in the blood. The most common antibodies from the group of immunoglobulins (Ig) G, IgM and IgA reaches typically 7-16 mg/ml for IgG, 0.4-2.3 mg/ml for IgA or 0.4-2.3 for IgM in serum, but the level can be signifi cantly increased due to some pathological processes including infectious diseases (64)(65)(66)(67). Amplifi cation of an stimuli is the major advantage of diagnoses based on antibodies assay, it means that a relatively low amount of antigen causes a signifi cantly higher production of antibodies and not the original antigen, but the propagated antibodies are detected.…”