Immunosensors Made with Layer-by-Layer Films on Chitosan/Gold Nanoparticle Matrices to Detect D-Dimer as Biomarker for Venous Thromboembolism

Autor(es)

Rodrigues, Valquiria C. ^[1] ; Moraes, Marli L. ^[2] ; Soares, Juliana C. ^[1] ; Soares, Andrey C. ^[1] ; Sanfelice, Rafaela ^[3] ; Deffune, Elenice ^[4] ; Oliveira Jr, Osvaldo N.

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Paulo, Unifesp, Campus Sao Jose dos Campos, Sao Jose Dos Campos, SP - Brazil

^[3] Univ Fed Triangulo Mineiro, Dept Chem Engn, Uberaba, MG - Brazil

^[4] UNESP, Dept Urol, Med Sch, Botucatu, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN; v. 91, n. 6, p. 891-896, JUN 2018.
• Citações Web of Science: 15

Resumo

We report on immunosensors to detect D-dimer, a biomarker of venous thromboembolism, which are made with layer-by-layer (LbL) films containing immobilized anti-D-dimer monoclonal antibody alternated with a layer of chitosan/gold nanoparticles (AuNpChi). Detection was due to irreversible adsorption of the antigen D-dimer on its corresponding antibody according to a Langmuir-Freundlich model, thus giving rise to ellipsoidal structures in scanning electron microscopy images whose size and number increased with D-dimer concentration. The chemical groups involved in the adsorption process were inferred from polarization-modulated infrared reflection absorption (PM-IRRAS) through changes in the amide and carbonyl bands. Detection of D-dimer was made with electrical impedance spectroscopy, electrochemical impedance spectroscopy and cyclic voltammetry. The latter was the most sensitive with a detection limit of 9 x 10(-4) mu g/mL, sensitivity of 0.27 x 10(-6) A/mu gmL(-1) with linear increase from 0 to 1 mu g/mL. The selectivity of the immunosensor made with AuNpChi/anti-D-dimer film was verified by noting negligible changes in the cyclic voltammograms when exposed to typical interferents in biological fluids. (AU)

• Processo FAPESP: 13/14262-7 - Filmes nanoestruturados de materiais de interesse biológico
• Beneficiário: Osvaldo Novais de Oliveira Junior
• Modalidade de apoio: Auxílio à Pesquisa - Temático