Electrospray induced surface activation of polystyrene microbeads for diagnostic applications. Issue 13 (26th February 2015)

• Record Type: Journal Article
• Authors: Foti, Leonardo; Sionek, Andre; Stori, Elis Moura; Soares, Paula Poli; Pereira, Miriam Marzall; Krieger, Marco Aurélio; Petzhold, Cesar Liberato; Schreiner, Wido Herwig; Soares, Maurílio José; Goldenberg, Samuel; Saul, Cyro Ketzer
• Is Part Of: Journal of materials chemistry. Volume 3:Issue 13(2015)
• Page Start: 2725
• Page End: 2731
• Publication Date: 2015-02-26
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Biomedical materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c4tb01884b
• Languages: English
• ISSNs: 2050-750X

Abstract

Abstract : Proposed electrochemical reaction mechanism: (a) highly charged microbeads approach the electrolyte; (b) microbeads sink and are solvated by water molecules; (c) water oxidation reaction disrupts PS surface bonds; (d) oxygen is incorporated into the polymer chains. Abstract : Electrospray is generally regarded as a "soft" technique due to the absence of any observable molecular fragmentation or destruction. This study reports on a novel and easy way to induce surface activation on the surface of polystyrene microbeads through electrospray deposition into a grounded aqueous electrolyte solution bath. This process, nicknamed EISA, which stands for electrospray induced surface activation, proposes that when a highly charged microbead formed by the electrospray process sinks into the aqueous electrolyte solution, it behaves like a highly charged spherical capacitor that discharges in the conductive liquid. The energy released leads to a breakup of the polystyrene surface bonds and water oxidation with oxygen. Further reactions produce a carboxylated surface that was confirmed by X-ray photoelectron spectroscopy (XPS) and protein coupling. An immunoassay based on these modified microbeads was also developed and presented for use in syphilis detection, demonstrating a reliable signal-to-noise ratio between positive and negative results.