title: Improving the sensitivity of immunoassays with PEG-COOH-like film prepared by plasma-based technique.
abstract: Herein we report on a preparation and performance of stable, hydrophilic and biocompatible polymeric material suitable for functionalization of disposable substrates used in biosensors. This new material features COOH surface groups cross-linked with ethylene glycol molecules and was prepared in situ on disposable, plastic substrate by high-throughput and environmentally friendly technique called plasma-enhanced chemical vapor deposition (PECVD). The film is grafted to the plasma activated plastic by sequential deposition of tetraethylorthosilicate, forming a bonding layer, and mixed vapors of acrylic acid and diethyleneglycol dimethylether (AA/PEG) that provide the desired functional groups forming a sensing, contact layer. A superior performance of the AA/PEG coating as suitable material for substrates in biomedical devices was demonstrated in a model fluorescence linked immunosorbent assay. The results were compared with other commonly used surface materials prepared by wet chemistry methods. The unique characteristic of the AA/PEG film is that the immunoassay can be executed without the need for a blocking step, typically using albumins, without negative consequences on the bioassay results. In fact, the superior quality of the materials modified with AA/PEG film was highlighted by improving the sensitivity of an immunoassay by two orders of magnitude when compared with substrates prepared by standard surface chemistry methods.
authors: Biomedical Diagnostics Institute, Dublin City University, Dublin 9, Ireland.
authors: Christy Charlton
authors: CC
authors: O'Mahony
authors: Vladimir
authors: V
authors: Gubala
authors: Ram Prasad
authors: RP
authors: Gandhiraman
authors: Stephen
authors: S
authors: Daniels
authors: Jong Seol
authors: JS
authors: Yuk
authors: Brian D
authors: BD
authors: Maccraith
authors: David E
authors: DE
authors: Williams
mesh_terms: D000179:Acrylates / Q000737:chemistry; D000906:Antibodies / Q000276:immunology; D005453:Fluorescence; D006801:Humans; D007118:Immunoassay / Q000379:methods*; D007164:Immunosorbents; D008422:Materials Testing / Q000379:methods*; D058626:Plasma Gases / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013499:Surface Properties; D014867:Water
chemical_list: D000179:Acrylates; D000906:Antibodies; D007164:Immunosorbents; D058626:Plasma Gases; D014867:Water; D011092:Polyethylene Glycols; C036658:acrylic acid