Tapered photonic crystal fibers coated with ultra-thin films for highly sensitive bio-chemical sensing

Abstract

Background: Photonic crystal fiber Mach-Zehnder modal interferometers based on no adiabatic tapered fibers are perspective for bio-chemical sensing, since they have very high refractive index sensitivity and it is possible for them to use a very small quantity of investigated samples. To obtain a desirable sensitivity to a needed analyte, it was proposed to coat a sensing surface of the refractive index sensor with ultra-thin films. Methods: In this work, we reported on a no adiabatic tapered special photonic crystal fiber coated with an ultrathin layer of a Bovine Serum Albumin (BSA) antigen or with an 8 nm palladium film to detect interaction between the BSA antigen and an anti-BSA antibody or for fast detection of hydrogen concentrations, respectively. Results and conclusion: During our experiments, we received a record detection limit of 125 pg/ml of the anti-BSA antibody concentration. Fast detection of hydrogen concentrations up to 5.6 vol% was carried out. By using a proposed electrodynamics model of a hydrogen sensor, an optimal taper sensing length was determined.

Modal Interferometers Based on a Tapered Special Photonic Crystal Fiber for Highly Sensitive Detection

“…Thus, the sensing of different gases or any other chemicals is observable. To confirm of the principle, we demonstrated the sensing of hydrogen [42,43]. Hydrogen is one of the cleanest energy sources.…”

A review of specialty fiber biosensors based on interferometer configuration

“…In addition to the measurement of pH by filling liquid crystal in PCF, the PCF sensor also realizes the rapid detection of most antigens and antibodies. The same year, Vladimir P Minkovich et al reported a non‐adiabatic tapered PCF probe that can detect biomolecules, as shown in Figure 7 [69]. The experimental results show that the detection limit of Bovine albumin (BSA) antibody concentration is 125 pg/mL.…”

“…A, The scanning electron microscope of photonic crystal fiber (PCF) cross section (left) and diagram of tapered PCF (right); B, Sensor response with anti‐BSA concentration between 0.125 and 125 ng/mL [69]…”

Dual parameter measurement system for temperature and stress based on Sagnac interferomter

“…Optical fiber sensor is a device, which is used for measuring various physical parameters by the changes of physical characteristics such as interference, diffraction, polarization, reflection and loss of light caused by light propagation in the optical fiber [1][2][3][4][5][6][7][8]. The optical fiber offer many excellent characteristics such as low loss, wide frequency band, large amount of information, small size, light weight, and good winding property.…”