Highly sensitive cholesterol concentration trace detection based on a microfiber optic-biosensor enhanced specificity with beta-cyclodextrin film

A beta-cyclodextrin (beta-CD) based optic-fiber microfiber biosensor for the detection of cholesterol concentration is propose and experimentally demonstrated. As an identifying substance, beta-CD is immobilized on the fiber surface for cholesterol reaction to form an inclusion complex. When the surface refractive index (RI) change is cause because of capturing the complex cholesterol (CHOL), the proposed sensor translates RI change into a macroscopic wavelength drift in the interference spectrum. The microfiber interferometer has a high RI sensitivity of 1251 nm/RIU and a low-temperature sensitivity of -0.019 nm/degrees C. This sensor can rapidly detect cholesterol in the concentration range of 0.001 to 1 mM and has a sensitivity of 12.7 nm/(mM) in the low concentration range of 0.001 to 0.05 mM. Finally, the characterization by infrared spectroscopy shows that the sensor can indeed detect cholesterol. This biosensor has a few strong advantages of high sensitivity and good selectivity, which expects great potential in biomedical applications.

Automated summary

This article introduces a β-cyclodextrin-based optical fiber microfiber biosensor for detecting cholesterol concentration, and demonstrates it experimentally.The β-cyclodextrin is immobilized on the fiber surface to form an inclusion complex with cholesterol, causing a change in surface refractive index and resulting in a macroscopic wavelength drift in the interference spectrum. The sensor has a high refractive index sensitivity of 1251 nm/RIU and a low temperature sensitivity of -0.019 nm/℃. It can rapidly detect cholesterol in the concentration range of 0.001 to 1 mM with a sensitivity of 12.7 nm/(mM) in the low concentration range of 0.001 to 0.05 mM. Characterization by infrared spectroscopy confirms the ability of the sensor to detect cholesterol. The biosensor has advantages of high sensitivity and good selectivity, showing great potential in biomedical applications.