| AVS 57th International Symposium & Exhibition | |
| Biomaterial Interfaces | Friday Sessions |
| Session BI+MN-FrM |
| Session: | Sensors & Fluidics for Biomedical Applications |
| Presenter: | G.R. Marchesini, Joint Research Centre, Italy |
| Authors: | G.R. Marchesini, Joint Research Centre, Italy S. Rebe Raz, Wageningen University, the Netherlands M.G.E.G. Bremer, RIKILT – Institute of Food Safety P. Colpo, Joint Research Centre, Italy G. Giudetti, Joint Research Centre, Italy W. Norde, Wageningen University, the Netherlands F. Rossi, Joint Research Centre, Italy |
| Correspondent: | Click to Email |
We present a novel approach to tackle the most common drawback of using Surface Plasmon Resonance for analyte screening in complex biological matrices - the nonspecific binding to the sensor chip surface.
By using a perforated membrane supported by a polymeric gel structure that exceeds the evanescent wave penetration depth, we created a filter above the sensing region that prevents the diffusion of large particles or aggregates that bind non specifically to the polymeric gel and interfere with SPR sensing, thus increasing assay’s sensitivity, reducing sample preparation steps and shortening the analysis time in total. A 10 nm thick non-fouling membrane with nanopatterned macropores was fabricated by means of colloidal lithography and plasma enhanced chemical vapor deposition of polyethylene oxide-like films. Such a membrane was supported by carboxymethyldextran, a polymeric gel matrix commonly used in surface plasmon resonance analysis. The surface was characterized using surface plasmon resonance imaging, contact angle, atomic force microscopy and scanning electron microscopy.
The performance of this surface in full fat milk and porcine serum was studied using an antibiotic detection immunoassay as a model system. Structurally, the 91.7 ± 14.7 nm diameter pores presented an hexagonal crystal lattice and a clearance of about 5 % of the total surface. Functionally, the nanopatterned macropores showed significant improvements in the quality of the obtained measurements in comparison to bare carboxymethyldextran, displaying 100 fold increase in the limit of detection of the enrofloxacin bioassay when performed in porcine serum.