Molecularly Imprinted Quartz Crystal Microbalance Sensor (QCM) for Bilirubin Detection

Abstract

This study aims the preparation of a QCM sensor for the detection of bilirubin in human plasma. Bilirubin-imprinted poly-(2-hydroxyethyl methacrylate-N-methacryloyl-L-tryptophan methyl ester) (PHEMATrp) nanofilm (MIP) on the gold surface of a QCM chip was synthesized by the molecular imprinting technique. Meanwhile, the non-imprinted PHEMATrp (NIP) nanofilm was synthesized by the same experimental technique to examine the imprinting effect. Characterization of MIP and NIP nanofilms on the QCM chip surface was achieved by atomic force microscopy (AFM), ellipsometry, Fourier transform infrared spectrophotometry-attenuated total reflectance (FTIR-ATR) and contact angle measurements (CA). The observations indicated that the nanofilm was almost in a monolayer. Thereinafter, the imprinted and the non-imprinted QCM chips were connected to the QCM system to investigate kinetic and affinity properties. In order to examine the selectivity of the MIP-PHEMATrp nanofilm, competitive adsorption of bilirubin with cholesterol and estradiol was performed. Limit of detection (LOD) and limit of quantitation (LOQ) values were calculated as 0.45 µg/mL and 0.9 µg/mL, respectively.

A molecularly imprinted nanofilm‐based quartz crystal microbalance sensor for the real‐time detection of pirimicarb

“…All the equilibrium‐adsorption‐desorption steps were repeated for each application at different concentrations. The Sauerbrey equation was used to estimate a linear relationship between the mass of a thin rigid film added to a quartz crystal surface and the changes in its resonant frequency . Because the frequency‐to‐mass conversion depends only on the physical and geometrical characteristics of the quartz crystal, it is widely used to relate the decrease in Δ f to the added Δ m for mass conversion in QCM applications.…”

“…The QCM is a simple, easy‐to‐use, cost‐effective, high‐resolution mass‐sensing technique that offers a quick response time and label‐free monitoring in real time; it has been favorably adopted for analytical chemistry and electrochemistry applications due to its sensitive solution‐surface interface measurement capability . Recently, QCM has been well adopted for analytical applications, considering the practical limitations of laboratory‐based methods, such as high cost, long processing times, instrumental complexity, and difficulty of manipulation . QCM sensors have been applied as transducers in analytical chemistry, biology, pharmaceutical detection, environmental assays,and life science …”

Sensitive detection of free bilirubin in blood serum using β-diketone modified europium-doped yttrium oxide nanosheets as a luminescent sensor

“…The detection limit (C LOD ) is dened by IUPAC and calculated by the formula C LOD ¼ 3S b /m. 35,36 The limits of detection of nanosheetstta/PS and nanosheets-dbt/PS were 41 nM and 138 nM, respectively. Compared to nanosheets-dbt/PS, nanosheets-tta/PS exhibits better linearity (R 2 ¼ 0.99154) and a lower detection limit.…”

Molecularly Imprinted Polymer Based Sensors for Medical Applications

“…They polymerized the bilirubin-imprinted nanofilm on the sensor surface and characterized by several measurements. They examined the kinetic and affinity properties of the bilirubin-imprinted sensor and calculated the detection limit value as 0.45 µg/mL [137]. The QCM sensor was provided for 17β-estradiol monitoring through the immobilization of the nanoparticles by Özgür et al The 17β-estradiol, natural steroid hormone, is one of the most potent endocrine disrupting compounds.…”