Adsorption according to the Langmuir-Freundlich model is the detection mechanism of the antigen p53 for early diagnosis of cancer

Author(s):Show less -

Soares, Juliana Coatrini ^[1] ; Soares, Andrey Coatrini ^[1] ; Raymundo Pereira, Paulo Augusto ^[2] ; Rodrigues, Valquiria da Cruz ^[1] ; Shimizu, Flavio Makoto ^[1] ; Melendez, Matias Eliseo ^[3] ; Neto, Cristovam Scapulatempo ^{[4, 3]} ; Carvalho, Andre Lopes ^[3] ; Leite, Fabio L. ^[5] ; Machado, Sergio A. S. ^[2] ; Oliveira, Jr., Osvaldo N. ^[1]

Affiliation

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

^[2] Univ Sao Paulo, Sao Carlos Inst Chem, BR-13560970 Sao Carlos, SP - Brazil

^[3] Barretos Canc Hosp, Mol Oncol Res Ctr, Barretos, SP - Brazil

^[4] Barretos Canc Hosp, Dept Pathol, Barretos, SP - Brazil

^[5] Univ Fed Sao Carlos, Sorocaba, SP - Brazil

• Document type: Journal article
• Source: Physical Chemistry Chemical Physics; v. 18, n. 12, p. 8412-8418, MAR 28 2016.
• Web of Science Citations: 19

Abstract

Biosensors for early detection of cancer biomarkers normally depend on specific interactions between such biomarkers and immobilized biomolecules in the sensing units. Though these interactions are expected to yield specific, irreversible adsorption, the underlying mechanism appears not to have been studied in detail. In this paper, we show that adsorption explained with the Langmuir-Freundlich model is responsible for detection of the antigen p53 associated with various types of cancers. Irreversible adsorption was proven between anti-p53 antibodies immobilized on the biosensors and the antigen p53, with the adequacy of the Langmuir-Freundlich model being confirmed with three independent experimental methods, viz. polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS), nanogravimetry using a quartz crystal microbalance and electrochemical impedance spectroscopy. The method based on this irreversible adsorption was sufficiently sensitive (limit of detection of 1.4 pg mL(-1)) for early diagnosis of Hodgkin lymphoma, pancreatic and colon carcinomas, and bladder, ovarian and lung cancers, and could distinguish between MCF7 cells containing the antigen p53 from Saos-2 cells that do not contain it. (AU)

• FAPESP's process: 13/14262-7 - Nanostructured films from biologically-relevant materials
• Grantee: Osvaldo Novais de Oliveira Junior
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 12/17689-9 - Preparation and characterization of bifunctional-nanostructured surfaces of Au-Pt obtained via templates for application in sensors and biosensors
• Grantee: Paulo Augusto Raymundo Pereira
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 12/15543-7 - Biosensors to detect Escherichia coli using the concept of an extended electronic tongue
• Grantee: FLAVIO MAKOTO SHIMIZU
• Support Opportunities: Scholarships in Brazil - Post-Doctoral