Acid sensors

Yang W, Fan H, Gao X et al (2004) The first fluorescent diboronic acid sensor specific for hepatocellular carcinoma cells expressing sialyl Lewis X. Chem Biol 11 439 148... 

Staudinger JL, Goodwin B, Jones SA, Hawkins-Brown D, Mackenzie KI, La-Tour A et al. The nuclear receptor PXR is a lithocholic acid sensor that protects against liver toxicity. Proc Natl Acad Sci USA 2001 98(6) 3 369 3374. 

A dual-transducer approach based on sol-gel optical sensors was recently reported to measure acid and salt concentrations in concentrated aqueous and HC1 solutions57. The acid sensors containing bromocresol purple, neutral red, and bromocresol green indicators were obtained by the immobilization of indicators in sol-gel derived films. The salt-HCl solution was flowed through the sensor cell58. 

F. Caruso, E. Rodda, D.F. Furlong, K. Niikura, and Y. Okahata, Quartz crystal microbalance study of DNA immobilization and hybridization for nucleic acid sensor development. Anal. Chem. 69, 2043-2049 (1997). 

J. Yeom, G. Z. Mozsgai, B. R. Flachsbart, et al. Microfabrication and characterization of a silicon-based millimeter scale, PEM fuel cell operating with hydrogen, methanol, or formic acid. Sensors Actuators B 107 (2005) 882-891. 

S. Uchiyama, H. Shimizu, and Y. Hasebe, Chemical amplification of uric acid sensor responses by dithiothreitol. Anal. Chem., 66, 1873-1876 (1994). 

Formic Acid Sensor. Formic acid is found in culture media. Therefore, on-line determination of formic acid is required. 

Glutamic Acid Sensor. A rapid automatic measurement of glutamic acid in fermentation media is required in fermentation industries. 

Absorption spectroscopic sensing, general discussion, 271 Acetic acid sensors, 334 Activities of ions, relation to interfacial potential difference, 369... 

An example of old PET signaling systems being applied to new purposes appears in the recent report on 23 as a boronic acid sensor by Wang and col-... 

The construction and electrochemical response characteristics of poly (vinyl chloride) membrane sensors for donepezil HC1 are described. The sensing membranes incorporate ion association complexes of donepezil HC1 cation and sodium tetraphenyl borate (sensor 1), or phospho-molybdic acid (PMA) (sensor 2), or phosphotungstic acid (sensor 3) as electroactive materials. The sensors display a fast, stable, and near-Nemstian response over a relative wide donepezil HC1 concentration... 

A more recent approach to designing direct fluorescent indicators for glucose involves two-component boronic acid sensors, where the fluorophore—usually anionic in nature—is quenched by a physically separate boronic acid-substituted viologen receptor. As the saccharide binds with the receptor, the quenching efficiency of the viologen is reduced, resulting in an increased emission intensity of the fluorophore (Figure 10.8). 

Cao H, Diaz DI, DiCesare N, Lakowicz JR, Heagy MD. Monoboronic acid sensor that displays anomalous fluorescence sensitivity to glucose. Organic Letters 2002, 4, 1503-1505. 

Miller and coworkers introduced pH-sensitive molecular sensors (Figure 5.4.6) for discovery of novel acylation catalysts [16]. Aminomethylanthracene was used as an acid sensor, because it undergoes photoinduced electron transfer (PET) when in... 

The nucleic acid sensor was prepared by first derivatizing the quartz surface with a 3 1 styrene-acrylic acid copolymer. Poly (A) was then covalently immobilized onto pendant carboxylic acid groups by amide bond formation with the amino groups on the adenine base. Hybridization occurred during incubation with poly(U). Following each of the three steps, the sensor was rinsed and dried and the resonant frequency of oscillation was measured. Prior to any treatment, the quartz crystals exhibited a resonant frequency of 9 MHz. Because each step in the surface treatment involved the addition of mass to the crystal surface, a frequency decrease was expected after each step. Figure 7.9 shows the actual frequency changes measured for a sensor prepared as described above, as well as for a sensor prepared with no poly(A) included in the second step (i.e., a control sensor). 

Threonine deprivation rapidly activates the system A amino acid transporter in primary cultures of rat neurons from the essential amino acid sensor in the anterior piriform cortex. J Nutr 133 2156-2164. 

Niijima A, Meguid MM. 1995. An electrophysiological study on amino acid sensors in the hepatoportaJ system in the rat. Obes Res 3 741S-745S. 

Tanaka K, Inoue S, Nagase H, Takamura Y, Niijima A. 1990. Amino acid sensors sensitive to alanine and leucine exist in the hepato-portal system in the rat. J Auton Nerv Syst 31 41-46. 

Staudinger, J.L., Goodwin, B., Jones, S.A., Hawkins-Brown, D., MacKenzie, K.I., LaTour, A., Hu, Y., Klaassen, C.D., Brown, K.K., Reinhard, J., Willson, T.M., Koller, B.H. and Kliewer, S.A. (2001) The nuclear receptor PXR is a lithocholic acid sensor that protects against liver toxicity. Proceedings of the National Academy of Sciences of the United States of America, 98, 3369-3374. 

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