title: Regenerative Surface Plasmon Resonance (SPR) biosensor: real-time measurement of fibrinogen in undiluted human serum using the competitive adsorption of proteins.
abstract: Epidemiological studies suggest that elevated plasma fibrinogen levels are associated with an increased risk of cardiovascular disorders. Normal fibrinogen level is in the range of 1.5-4.5mg/mL, depending upon both genetic (intrinsic) and environmental (extrinsic) factors. An increase of 0.25mg/mL from the normal level can often be correlated with a high risk of cardiovascular disease. Thus, it is useful to monitor fibrinogen level in serum of a patient for clinical diagnosis. We report a regenerative biosensor that measures real-time fibrinogen levels in undiluted serum. The biosensor uses Surface Plasmon Resonance (SPR), highly sensitive optical technique. The biosensor does not use bio-receptors (i.e., antibodies, enzymes, DNA, etc.) unlike conventional biosensors, and deploys the nature of competitive adsorption of proteins to achieve selective detection of fibrinogen. We measured fibrinogen-spiked serum samples with a concentration of 1.5-4.5 mg/mL, and repeated six measurement trials to obtain statistical distribution of the measurements using the regeneration method of the sensing surface. The SPR biosensor has a sensitivity of 42 mDeg/(mg/mL) for a fibrinogen concentration in the range of 0.5-2.5 mg/mL, whereas it was hard to correlate the measurements to the spiked-fibrinogen samples of above 2.5 mg/mL.
authors.affiliation: School of Electrical, Computer, and Energy Engineering, Arizona State University, AZ 85287, USA. rwang32@asu.edu
authors.forename: Ran
authors.initials: R
authors.lastname: Wang
authors.forename: Arad
authors.initials: A
authors.lastname: Lajevardi-Khosh
authors.forename: Seokheun
authors.initials: S
authors.lastname: Choi
authors.forename: Junseok
authors.initials: J
authors.lastname: Chae
mesh_terms: D000327:Adsorption; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D005340:Fibrinogen / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D012680:Sensitivity and Specificity; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D005340:Fibrinogen