Protein assays

Wolfe, C. A. C. Oates, M. R. Hage, D. S. Automated Protein Assay Using Flow Injection Analysis, /. Chem. Educ. 1998, 75, 1025-1028. 

This experiment describes the adaptation of the bicinchoninic acid (BCA) protein assay to a flow injection analysis. The assay is based on the reduction of Cu + to Cu+ by the protein, followed by the reaction of Cu+ with bicinchoninic acid to form a purple complex that absorbs at 562 nm. Directions are provided for the analysis of bovine serum albumin and rabbit immunoglobulin G, and suggestions are provided for additional analyses. 

Recently, a reagent that reacts more efficiently with Cn than Folin-Ciocalteau reagent has been developed for protein assays. Bieinehoninie aeid (BCA) forms a purple complex with Cu in alkaline solution. 

Mixing of the Coomassie Plus Protein Assay Reagent... 

Mclssac and Joshl, M. S. "Prenatal Detection of Neural Tube Defects. Comparison Between Alpha Fetoprotein and Beta-Trace Protein Assays". Amer. J. Obstet. Gynecol,... 

All fractions were analysed for AE activity and protein content. The protein content was measured spectrophotometrically according to Bradford using the BioRad protein assay kit with Y-globulin as standard (5). 

The protein content was determined using a commercial assay kit (Bio-Rad Protein Assay kit) with Bovine Serum Albumin as standard, following the procedure described by Bradford [13]. 

Here m is the slope value and [ii]app is the apparent total enzyme concentration, typically estimated from protein assays and other methods (Copeland, 1994). Note from Equation (7.13) that when our estimate of enzyme concentration is incorrect, the slope of the best fit line of IC50 as a function of [E] will not be 1/2, as theoretically expected. Nevertheless, the v-intercept estimate of K pp is unaffected by inaccuracies in [ ]. In fact we can combine Equations (7.12) and (7.13) to provide an accurate determination of [ /]T from the slope of plots such as those shown in Figure 7.2. The true value of [ii]T is related to the apparent value [ TPP as... 

Zichi D., Koga T., Greef C., Ostroff R., Petach H., Photoaptamer technology development of multiplexed microarray protein assays, Clin. Chem. 2002 48 1865-1868. 

Material required For total protein extract and enzyme activities extraction buffer 50 mM potassium phosphate, pH 7.0,1 mM EDTA, 1% of PVP (100 mg/mL), for CAT, GR, and SOD and with 10 mM ascorbato for APX activity. Bio-Rad protein assay, centrifuge, spectrophotomer and quartz cuvette. 

Protein content The amount of protein in each extract can be determined by the Bradford method (Bradford, 1976), using BSA as a standard. Briefly, make a standard curve with 0,2,4,6,8,10,15 and 20 pg / mL BSA and mixed with 1 mL of Bio-Rad protein assay (diluted 1 4). Read standard curve and samples at A595 in a spectrophotometer, using as blank 1 mL of diluted Bio-Rad protein assay. 

Determine the amount of adsorbed protein on the particles by using a suitable protein assay technique, such as the bifunctional chelating agents (BCA) Protein Assay (Thermo Fisher). 

Dowers Grove, IL), insulin by a radio immunoassay by means of Coat-A-Count Insulin Detection Kit (Diagnostic Products Corp., Los Angeles, CA), and proteins by Bio-Rad Protein Assay (Bradford) method (Bio-Rad, Hercules, CA). 

Quantification of total protein in the final product represents another standard analysis undertaken by QC. A number of different protein assays may be potentially employed (Table 7.3). 

Assay of Protein Content. Protein content is measured by a protein assay kit (Bio-Rad, Hercules, CA). Assay is performed according to the manufacturer s instructions. 

Chemical assays such as total protein assays and analytical chemistry including spectroscopy and chromatography. 

Stengelin, M., Hudson, K., Bedzyk, W. D., Singh, P., Desai, V., LeBlanc, M., Berg, M., Murray, V. and Bauer, R. Development and performance of a high-sensitivity C-Reactive Protein assay for the Stratus CS STAT fluorometric analyzer , Clin. Chem., 46, 26 (Abstract) (2000). 

The number of multiplexed particles-based assays reported is manifold and summarized in several reviews [85, 86, 97, 99], Bead sets for various nucleic acid or protein assays are commercially available that are fully optimized for clinical diagnostics and research purposes. 

An L, Tang Y, Wang S, Li Y, Zhu D (2006) A fluorescence ratiometric protein assay using light-harvesting conjugated polymers. Macromol Rapid Commun 27 993-997... 

A standard Lowry-based protein assay has been adjusted to the special conditions encountered with skin [126], Basically, proteins reduce an alkaline solution of Cu(II)-tartrate to Cu(I) in a concentration-dependent manner. Then, the formation of a blue complex between Folin-Ciocalteau reagent (a solution of complex polymeric ions formed from phosphomolybdic and phosphotungstic heteropoly acids) and Cu(I) can be measured spectrophotometrically at 750 nm. A calibration curve can be obtained by dissolving known amounts of stratum corneum in 1 M sodium hydroxide. A piece of tape that has not been in contact with skin is subjected to an identical procedure and serves as negative control. The method was recently adapted to a 96-well plate format, notably reducing analysis times [129],... 

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