Sucrose sensors

FIG. 10 Schematic drawing of the design of (a) an S-layer-based amperometric glucose sensor, (b) a sucrose sensor, and (c) an optical glucose sensor. 

Lager, I., Looger, L. L., Hilpert, M., Lalonde, S. and Frommer, W. B. (2006). Conversion of a putative Agrobacterium sugar-binding protein into a FRET sensor with high selectivity for sucrose. J. Biol. Chem. 281, 30875-83. 

Yeast cells are able to metabolize many types of sugars. In this experiment, you will observe the fermentation of sugar by baker s yeast. When yeast cells are mixed with a sucrose solution, they must first hydrolyze the sucrose to glucose and fructose. Then the glucose is broken down in the absence of oxygen to form ethanol and carbon dioxide. You can test for the production of carbon dioxide by using a CBL pressure sensor to measure an increase in pressure. 

Dosivit, Nantes, France MC2 Multisensor Glucose, sucrose, lactose, lactate, ethanol Electrochemical enzyme sensor Agriculture, food... 

The continuous configurations depicted in Figs 5.12.D1 and 5.12.D2 were designed by Nieman s group for application of this sensor to the determination of sucrose (and glucose) in soft drinks, breakfast cereal and cake mix [36]. The analyte is converted into /3-D-glucose, to which the sensor is responsive, in two reaction steps that are catalysed by invertase (INV) and mutarotase (MUT) ... 

Biosensors are also available for glucose, lactate, alcohol, sucrose, galactose, uric acid, alpha amylase, choline, and L-lysine. All are amperometric sensors based on O2 consumption or H2O2 production in conjunction with the turnover of an enzyme in the presence of substrate. In the case of glucose oxidase reaction, the normal biological reaction is ... 

Matsumoto et al (41) prepared a multi-enzyme electrode using glucose oxidase, invertase, mutarotase, fructose-5-dehydrogenase, and catalase to simultaneously detect glucose, fructose, and sucrose in fruit juices and soft drinks. Detection of multi-components by enzyme sensors was also reported in analysis of sucrose and glucose in honey (42) and drinks (43), and L-malate and L-lactate in wines (44). 

Electrochemical transducers work based on either an amperometric, potentio-metric, or conductometric principle. Further, chemically sensitive semiconductors are under development. Commercially available today are sensors for carbohydrates, such as glucose, sucrose, lactose, maltose, galactose, the artificial sweetener NutraSweet, for urea, creatinine, uric acid, lactate, ascorbate, aspirin, alcohol, amino acids and aspartate. The determinations are mainly based on the detection of simple co-substrates and products such as 02, H202, NH3, or C02 [142]. 

Several other sensors are available that are based on the amperometric measurement of hydrogen peroxide produced by enzymatic reactions. The analytes measured include sucrose, lactose, ethanol, and L-lactate. A different enzyme is, of course, required for each species. In some cases, enzyme electrodes can be based on measuring oxygen or on measuring pH. 

Various research groups have developed enzyme electrodes for the determination of sucrose. The operational parameters of these sensors are listed in Table 10. 

For the determination of AA, two non-enz3miatic sensors based on PANI-CNT composites were developed that differ from each other in the electrode composition. The catal ftic effect of copper nanoparticles (CuNPs] was utilized in one of the approaches [47] and the other was based on an electropolymerized poly(2,5-dimethoxyaniline]-NH2-MWCNT film [48]. Both sensors showed selective oxidation of AA in the presence of DA and UA at 0.4 and 0.28 V, respectively. The interference from 10 pM glucose, oxalic acid, fructose, lactose, NaCl, sucrose, and tartaric acid was negligible in 0.1MAA[47]. 

Surface Plasmon Resonance Sensors, Fig. 4 Sample sensitivity measurements using solutions of different refractive indices made using the nanohole SPR device shown in Fig. 2. Transmission spectra were obtained through a 450 nm periodicity array for the cases of pure water, sucrose solutions with increasing refractive index,... 

Food industry Biosensors based on CPs have been developed for quality control in food industry [113,225-227], The spectrum of these sensors ranges from detection of food-borne pathogens [228-234] and qualitative assessment of freshness of meat [235] to estimation of glucose, sucrose, lactate, citric acid, ascorbic acid, etc. in food products. 

---