Nanoparticles-based nanochannels assembled on a plastic flexible substrate for label-free immunosensing

• Published in: Nano research Vol. 8; no. 4; pp. 1180 - 1188
• Main Authors: Escosura-Muñiz, Alfredo de la, Espinoza-Castañeda, Marisol, Hasegawa, Madoka, Philippe, Laetitia, Merkoçi, Arben
• Format: Journal Article
• Language: English
• Published: Beijing Tsinghua University Press 01.04.2015; Springer Nature B.V
• Subjects: Aluminum; Atomic/Molecular Structure and Spectra; Biomedicine; Biotechnology; Chemistry and Materials Science; Condensed Matter Physics; Detection; Electrodes; Human; Immunoglobulins; Indium tin oxide; Indium tin oxides; Laboratories; Materials Science; Membranes; Nanoparticles; Nanospheres; Nanostructure; Nanotechnology; Platforms; Polyethylene terephthalate; Polyethylene terephthalates; Polystyrene resins; Proteins; Research Article; Thin film coatings; Tin; 传感; 免疫复合物; 无标记; 柔性基板; 检测系统; 纳米粒子; 纳米通道; 蛋白质检测; Switzerland; Spain; nanochannel; dip-coating; label-free immunosensing; electrochemical biosensor
• ISSN: 1998-0124; 1998-0000
• DOI: 10.1007/s12274-014-0598-5

A novel, cheap, disposable and single-use nanoparticles-based nanochannel platform assembled on a flexible substrate for label-free immunosensing is pre- sented. This sensing platform is formed by the dip-coating of a homogeneous and assembled monolayer of carboxylated polystyrene nanospheres （PS, 200 and 500 nm-sized） onto the working area of flexible screen-printed indium tin oxide/polyethylene terephthalate （ITO/PET） electrodes. The spaces between the self-assembled nanospheres generate well-ordered nanochannels, with inter-PS particles distances of around 65 and 24 nm respectively. The formed nanochannels are used for the effective immobilization of antibodies and subsequent protein detection based on the monitoring of [Fe（CN）6]^4- flow through diffusion and the decrease in the differential pulse voltammetric signal upon immunocomplex formation. The obtained sensing system is nanochannel-size dependent and allows human immunoglobulin G （IgG） （chosen as a model analyte） to be detected at levels of 580 ng/mL. The system also exhibits an excellent specificity against other proteins present in real samples and shows good performance with a human urine sample. The developed device represents an integrated and simple biodetection system which overcomes many of the limitations of previously reported nanochannels-based approaches and can be extended in the future to several other immuno and DNA detection systems.