Cephalosporin sensors

Cephalosporine Sensor. Simple, continuous methods for antibiotic determination are required for fermentation industries. Citrobacter freundii produced cephalosporinase, which catalyzes the following reaction of cephalosporin, which liberates hydrogen ions ... 

Figure 4. Response curve of the cephalosporin sensor. The concentration of Phenylacetyl-7ADCA tvas 1. 250 y/tnL 2. 62.5 y/mL.

Figure 5. Calibration curves of the cephalosporin sensor. ( ) Phenulacetyl-7 ADC A, ("Hj cephalosporin C,(0) CET, ( ) CER.

Figure 6. Reusability of the cephalosporin sensor. Phenylacetyl-7ADCA (125 y/mL) was employed for experiments.

Cephalosporin is determined from the proton concentration generated in a medium by using immobilized bacteria. A microbial sensor composed of a bacteria-collagen membrane reactor and a combined glass electrode was applied to the determination of cephalosporins in fermentation media. The system used for continuous determination... 

The reusability of the microbial sensor was examined with a solution containing 125/ ig ml- of phenylacetyl-7ADCA. The cephalosporin determination was carried out several times a day, and no change in the potential difference response was observed for a week. 

Figure 4. Immobilized whole cell-based flow-type sensor for cephalosporins. 1. Soda lime 2. Buffer reservoir 3. Peristaltic pump 4. Sample inlet 5. Immobilized whole cell reactor 6. Combined glass electrode 7. Sensing chamber 8. Amplifier 9. Recorder...

Figure 3. Scheme of the microbial electrode sensor for cephalosporins. 1. Soda... 

The properties of spinach chloroplasts adsorbed onto diethylaminoethyl-cellulose have been reported and the immobilized chloroplasts used for the continuous photoreduction of 2,6-dichloroindophenol as an indicator of photosystem II activity in the chloroplasts. The formation of ATP from ADP and orthophosphate via the cyclic photophosphorylation system has been achieved using chloroplasts copolymerized with polyvinylalcohol onto an electrode. Citrobacter freundii cells immobilized by co-casting with collagen have been used in a flow type sensor for cephalosporins. ... 

Citrobacter freundii cells - Co-casting with collagen Immobilized whole cell-based flow type sensor for cephalosporins 666... 

The antiwear behavior of P-lactam cephalosporin antibiotics such as cefixime, cefadroxil, and cephalexin has been studied using the Four Ball lubricant tester in paraffin oil (14MI30500). A novel electrochemical sensor... 

The next group of multimembrane systems comprises membranes sensitized biologically using immobilized enzymes or microorganisms. Species that are directly sensed by an ISE are produced in the enzymatic reaction of the analyte. Examples of such sensors are those used for determination of urea in milk, based on immobilized urease and measurement of a pH change. An example of the application of bacteria strains is the use of immobilized recombinant Escherichia coli coupled with a pH electrode. Such electrodes have been used for determination of cephalosporins. When this bacterial strain is coupled with a CO2 gas sensor, glutamic acid determination can be carried out. 

Other metabolites that have been measured with calorimetric sensors include ascorbic acid, ATP/ADP (adenosine 5 -diphosphate), cephalosporins, galactose, hydrogen peroxide, lactose, malate, phospholipids, uric acid, xanthine, and hypoxanthine. 

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