Plasmonic biosensor detected human chorionic gonadotropin with naked eye

The traditional surface plasmon resonance (SPR) instrument has the advantages of real time, label-free and high sensitivity. This study mainly makes the traditional SPR instruments miniaturized into active plasmon colorimetric biosensors, which is used for point of care and further improve the medical Level. Nano-printed technology is a simple process technology that used in the preparation of nano-structure with advantages of low cost and high production, for the future active plasmon colorimetric biosensors manufacturing has a very high Production advantages. Organic light emitting diodes have the uniformity of light intensity at different angles, which is one of the indispensable conditions in the detection process of plasmon bioassay. In this experiment, it is proved that the grating period is 555 nm, when the refraction value change from 1 to 1.33 the coupling wavelength shifted about 190 nm, the minimum refractive index is 1.736×10^-3 RIU. The binding reaction with β-hCG (1 μM) was enhanced by the bonding of Peptide (1 mM) with gold nanoparticles (15 nm), which was about 43.88 times higher than that of the original peptide (1 mM) and β-hCG (1 μM). That the minimum refraction value of the change in the sensitivity increased to 3.956×10^-5 RIU. After the peptides (33 nm) bonded Peptide (1 mM) and β-hCG (1 μM) were used for the active plasmon colorimetric biosensors. The plasmon at a measuring angle of 5 ° wavelength of the emission shifted 16 nm, and the measurement angle is 4 nm at the measuring angle of -5 °.