Colorimetric detection

Elghanian, R., Storhoff J.J., Muck, R.C., Letsinger, R.L. and Mirkin, C.A. (1997) Selective colorimetric detection of polynucleotides based on the distance-dependent optical properties of gold nanoparticles. Science, 277, 1078-1081. 

For example, assays based on fluorimetric or colorimetric detections are highly sensible to fluorescent and colored compounds. 

SCX column was used to separate oxalate and urate.140 In this separation, differential pulse and DC amperometric detection were compared. Differential pulse detection was found to allow better selectivity in detection. Anion exchange on Diaion CA08 was used to separate 20 carboxylic acids in the analysis of white wine, as shown in Figure 10.141 Because many carboxylic acids have a relatively weak absorbance, detection is difficult. The colorimetric detection scheme shown in the figure may be useful in some applications. 

CMC-2, HW-55(S) Fractogel TSK E. Merck, Darmstadt, pH 5, 0.02% NaN3 0.05 MNa2S04,0.05 M NaAcetate Orcinol-H2S04, post-column with colorimetric detection (X= 420 nm)... 

Gurtu, V., Kain, S. R. and Zhang, G. (1997). Fluorometric and colorimetric detection of caspase activity associated with apoptosis. Anal. Biochem. 251, 98-102. 

In conclusion, CL ISH has proved more sensitive than ISH followed by colorimetric detection and can be as sensitive as ISH using radioactive labels [31, 32, 64, 65], When compared with fluorometric detection, CL showed an improved signal-to-noise ratio, thus a higher specific detectability furthermore, once standardized, it provided more precise and accurate quantitative results. 

Charych, D. H. Nagy, J. O. Spevak, W. Bednarski, M. D., Direct colorimetric detection of a receptor ligand interaction by a polymerized bilayer assembly, Science. 1993, 261, 585 588... 

N4. Nordin, J. H., and Bretthauer, R. K., Colorimetric detection of carriers of galactosemia based on thionicotinamide diphosphopyridine nucleotide (TNDPN) reduction. Federation Proc. 20, 256 (1961). 

We have looked in detail at the analysis of nutrients in natural water, as this is of considerable interest globally, in terms of the overall effect on water quality, and in particular, the prevention of algal blooms which have become an all-too familiar problem in many countries. Bearing in mind the need for inexpensive components and the requirement of low-power operation, we have focused on colorimetric detection using LED/photodiode detection in a microfluidic manifold as a generic... 

Water and waste water (APHA Method 4500-CN M) Filtration of sample optional treatment with resin treatment with ferric nitrate solution Colorimetric detection (thiocyanate) No data 71-99, 0.07-1.42 mg/L APHA 1992... 

Waste or leachate (EPA Method 901OA) Reflux-distillation of acidified sample absorption of released HCN in NaOH treatment with AgNOs and an indicator (titrimetric) or chloramine-T/pyridine-barbituric acid (colorimetric) Titrimetric or colorimetric detection (total and amenable cyanide) 0.1-0.2 mg/L titrimetric) 0.02 mg/L (colorimetric) (Titrimetric) 94-99 (total cyanide), 87-97 (amenable cyanide) EPA1992d... 

Solid waste or oil waste (EPA Method 9013) Extraction of solid component with water at pH >10 and hexane Titrimetric or colorimetric detection (soluble cyanides) No data 60-90 (solid) 88-92 (oil) EPA1992e... 

Fig. 8 (top) Liposome with polydiacetylene linked monolayer mixed with ligand for receptor detection. (bottom) Colorimetric detection of influenza virus using polymerized liposomes to which have been added increasing amounts of influenza virus from left to right. [18]... 

Reichert A, Nagy JO, Spevak W, Charych D (1995) Polydiacetylene liposomes functionalized with sialic-acid bind and colorimetrically detect influenza-virus. J Am Chem Soc 117 829-830... 

Table 10.8 Reagents for the colorimetric detection of amino acids... 

CFA with ISE detection has been applied to determinations with enzyme electrodes [81]. It has been shown [115] that potentiometric detection with ISEs is superior to colorimetric detection in its simpler methodology, high selectivity, a wide linear dynamic range, and insensitivity to solution colouration... 

Gallagher, R.I. Reverse phase protein microarrays fluorometric and colorimetric detection... 

Gallagher RI, Silvestri A, Petricoin EF et al (2011) Reverse phase protein microarrays fluorometric and colorimetric detection. Methods Mol Biol 723 275-301... 

We (K1) attempted to develop a noncompetitive assay based on the anti-idiotype antibodies for a conjugated bile acid metabolite, ursodeoxycholic acid 7-A-acetyl-glucosaminide (UDCA 7-NAG), which is expected to serve as a diagnostic index for an autoimmune disease, primary biliary cirrhosis. In our assay, the hapten UDCA 7-NAG, a /3-type antibody, and a biotin-labeled a-type antibody were simultaneously added to a microtiter plate coated with an F(ab )2 fragment of a specific anti-UDCA 7-NAG antibody, then incubated at room temperature for 8 h. Bound biotin was then detected with HRP-labeled streptavidin, whose enzyme activity was measured using o-phenylenediamine/H202 as a substrate. This noncompetitive assay system provided a subfemtomole-order sensitivity (detection limit 118 amol) that was 7 times lower than the competitive immunoassay using the same anti-hapten antibody (K2), even with a common colorimetric detection (Fig. 13). Somewhat improved specificity was also obtained namely, better... 

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