Theophylline sensor

LAI E P C, FARFARA A, VANDERNOOT V A, KONO M and POLSKY B (1998), Surface plasmon resonance sensors using molecularly imprinted polymers for sorbent assay theophylline, caffeine and xanthan , Can J Chem, 76, 265. 

Haga et al. developed another type of immunosensor by combining an enzyme membrane immunoassay and an enzyme sensor using oxygen electrodes (HI). In this assay antigen molecules (theophylline) are attached on the surface of the liposomes and an enzyme (horseradish peroxidase) is encapsulated in the sensitized liposome. When antibody (antitheophylline antibody) and complement are added, the enzyme is released by the liposome lysis. The enzyme activity with the NADH-NAD reaction can be determined by the oxygen electrode. When antigen is added, it competitively binds to antibodies, then liposome lysis and enzyme activity are decreased. The sensitivity of this method for theophylline determination was reported as 0.7 ng/ml. 

HI. Haga, M., Sugawara, S., and Itagaki, H., Drug sensor Liposome immunosensor for theophylline. Anal. Biochem. 118, 286-293 (1981). 

Theophylline-imprinted polymers prepared with MAA and EDMA were utilized for SPR sensors, in which the particles were immobilized on the silver film on the SPR sensor chip by evaporation from acetonitrile-acetic acid (99 1 v/v) containing the particles [20]. The detection limit was reported to be 0.4 mg/mL of theophylline in aqueous solution. 

Lai, E.P.C. Fafara, A. VanderNoot, V.A. Kono, M. Polsky, B. Surface plasmon resonance sensors using molecularly imprinted pol5mers for sorbent assay of theophylline, caffein, and xanthine. Can. J. Chem. 1998, 76, 265-273. 

E. E. Ferapontova and K. V. Gothelf, Effect of serum on an RNA aptamer-based electrochemical sensor for theophylline, Langmuir, 25, 4279-4283 [2009b],... 

In pharmaceutical fields, in Zhang Z. et al., 2010b, a novel sensitive and selective imprinted electrochemical sensor was constructed for the direct detection of L-histidine by combination of a molecular imprinting film and MWNTs. The sensor was fabricated onto an indium tin oxide electrode via stepwise modification of MWNTs and a thin film of MIPs via sol-gel technology. The introduced MWNTs exhibited noticeable enhancement on the sensitivity of the MIPs sensor, meanwhile, the molecularly impainted film displayed high sensitivity and excellent selectivity for the target molecule. H. Y. Lee Kim, 2009 reports of the synthesis of CNTs-MIP composite to be potentially applied to probe materials in biosensor system for theophylline recognition based on CNT field effect. Hydroxyl-... 

X.C. Tan, L. Wang, P.F. Li, Q. Gong, L. Liu, D.-D. Zhao, F.H. Lei and Z.Y. Huang, Electrochemical sensor for the determination of theophylline based on molecularly imprinted polymer with ethylene glycol maleic rosinate acrylate as cross-hnker, Acta Chim. Sinica, 70 (9) 1088-1094, 2012. 

---