Luciferase immobilized

The biosensor had following characteristics 0.1 mL preparation of luciferase immobilized into starch gel disc, diameter 7-8 mm, width 50 fim, dry weight 9 0.5 mg. The enzyme activity in the disc increases with increasing the activity of soluble luciferase preparations used for immobilization. ... 

Bioluminescence can also be used as the basis for immunoassay. For example, bacterial luciferase has been used in a co-immobilized system to detect and quantify progesterone using a competitive immunoassay format (34), and other luciferase-based immunoassays have been used to quantify insulin, digoxin, biotin, and other clinically important analytes (35). 

Holzman, T. F., and Baldwin, T. O. (1982). Isolation of bacterial luciferases by affinity chromatography on 2,2-diphenylpropylamine-Sepharose phosphate-mediated binding to immobilized substrate analogue. Biochemistry 21 6194-6201. 

For luciferin, a firefly luciferase cosubstrate, another method of retention has been evaluated which consisted of incorporating the substrate in acrylic microspheres during their formation, these last being then confined in a polymeric matrix31. Using the suitable co-immobilized enzymes (adenylate kinase and creatine kinase), the three adenylic nucleotides (ATP, ADP and AMP) could be assayed continuously and reproducibly with a selfcontainment working time of 3 h. 

Chemical immobilization procedures of bioluminescent enzymes such as firefly luciferase and bacterial luciferase-NAD(P)H FMN oxidoreductase to glass beads or rods [174, 175], sepharose particles [176], and cellophane films [177] have produced active immobilized enzymes. Picomole-femtomole amounts of ATP or NAD(P)H could be detected using immobilized firefly luciferase or bacterial luciferase-oxidoreductase, respectively. 

Sensitive flow-injection analyses of aspartate, glutamate, 2-oxoglutarate, and oxaloacetate were developed using immobilized bacterial luciferase enzymes. 

Irregular and flat surfaces Firefly luciferin/luciferase HRP/H202/luminol AP/dioxetanes Firefly luciferin/luciferase Bacterial luciferin/luciferase Detection of ATP as an indicator of microbial contamination Evaluation of the spatial distribution of immobilized biomolecules... 

Figure 2 Effect of enzyme immobilization on luminescent image spatial resolution evaluated using coupled enzymatic reactions on nylon net as a model system, (a) Immobilized 3a-hydroxysteroid dehydrogenase (b) immobilized 3a-hydroxysteroid dehydrogenase and FMN-NADH oxidoreductase (c) immobilized 3a-hydroxysteroid dehydrogenase, FMN-NADH oxidoreductase, and bacterial luciferase. (From Ref. 47. Copyright John Wiley Sons Ltd. Reproduced with permission.)...

In the method shown in Figure 9B, a firefly luciferase gene is introduced for sensitive bioluminescent detection of target DNA [5], The luciferase-coding DNA requires no posttranslational modification, and the activity of the luciferase produced can be readily measured in the transcription/translation mixture without prior purification. In this assay system, the digoxigenin-labeled probe is first immobilized to polystyrene wells coated with antidigoxigenin antibody. The target... 

The first insoluble derivatives of bioluminescent enzymes were prepared by Erlanger et al. by reacting luciferases they investigated the properties of these immobilized enzyme preparations and their potential for studying the mechanism of bioluminescence [54]. 

The LDH+ALT reactor provided a linear response from 0.1 to 50 pmol/L lactate, thereby increasing lactate conversion by 117-183% relative to LDH alone. The intra- and inter-assay CV were both less than 5%, and recoveries ranged from 93 to 106%. Even though roughly 100% of the LDH and ALT added bound to the support under the immobilization conditions used, the activities of the immobilized enzymes were ca. 3% of those of the free enzymes, which is consistent with previous results obtained by the same [67] and other authors [69,70]. Jointly immobilized LDH and ALT preserved ca. 50% of their original activity after 60-90 days of intermittent use. On the other hand, immobilized luciferase was less markedly inhibited than that in the free solution by substances present in the biological samples assayed [71]. 

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