Amperometric detection of bilirubin from a micro-sensing electrode with a synthetic bilirubin imprinted poly(MAA-co-EGDMA) film.
Poly(methacrylic acid-co-ethyl glycol dimethylacrylate) (poly(MAA-co-EGDMA)) imprinted with alpha-bilirubin was shown to be able to bind alpha-bilirubin in our previous work. In this work, the corresponding imprinted polymer thin film was synthesized onto a thiol treated Au electrode by surface grafting polymerization. Bilirubin was able to be detected by an Au electrode, however, the electrode was not be able to discriminate bilirubin from the other matrix components if clinical samples were used. Therefore, the imprinted material was introduced so that the modified Au electrode could specifically detect bilirubin. Optimal potential was found to be 0.55 V and this was set for the rest of experiments. The imprinting factor of 3.16 was confirmed by comparing the signals from the MIP-Au and the NIP (non-imprinted polymer)-Au electrode. Calibration of the bilirubin concentration with respect to the current by the MIP-Au electrode was made within the range of 5mg/dl and a detection sensitivity of 0.644 microA/mg/dl (2.58 microA/cm(2)/mg/dl) was obtained. Furthermore, a linear correlation of the bilirubin concentration within 1.0mg/dl versus detection current was also achieved. Bilirubin was further detected by the MIP-Au electrode in the presence of fetal bovine serum (FBS). Repeated detection of bilirubin with at least three detection batches was performed and the reproducibility of the same piece of MIP-Au electrode was confirmed. The result was compared to those obtained from the serum and the solvent solution. The results indicated the feasibility of using the bilirubin imprinted poly(MAA-co-EGDMA) film as a sensing electrode for the clinical detection of bilirubin in serum.
Syu
Mei-Jywan
MJ
Department of Chemical Engineering, National Cheng Kung University, Tainan 701, Taiwan. syumj@mail.ncku.edu.tw
Chiu
Tsung-Chieh
TC
Lai
Chune-You
CY
Chang
Yong-Sheun
YS
D001663:Bilirubin / Q000097:blood* / Q000737:chemistry*; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001774:Blood Chemical Analysis / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005026:Ethylene Glycols / Q000737:chemistry*; D008689:Methacrylates / Q000737:chemistry*; D008839:Microelectrodes; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013499:Surface Properties
D005026:Ethylene Glycols; D008689:Methacrylates; C502776:poly(methacrylic acid-ethylene glycol dimethacrylate); D001663:Bilirubin