Metalloimmunoassays

Metallocomplexes Metalloenzymes Metalloid peroxides Metalloimmunoassays Metallomesogens... 

M. Dequaire, C. Degrand, and B. Limoges, An electrochemical metalloimmunoassay based on a colloidal gold label. Anal. Chem. 72, 5521-5528 (2000). 

X. Chu, X. Fu, K. Chen, G. Shen, and R. Yu, An electrochemical stripping metalloimmunoassay based on silver-enhanced gold nanoparticle label. Biosens. Bioelectron. 20, 1805-1812 (2005). 

Scheme 1.11 Representative organometallic tracers used in metalloimmunoassays.

Cais, who coined the term metalloimmunoassay, prepared a series of organometallic markers (metallohaptens) with the potential for use in immunoassay. These are derivatives of steroids (estradiol, estriol), mood-altering drugs (amphetamine and cocaine) or medications (morphine and barbiturates), labeled with ferrocene, cobaltocenium and cymantrene [57-59]. He then assessed the use of a Sepharose 4B column to separate the free and bound fractions of the tracer and quantification of the tracer by atomic absorption spectrometry [58]. 

Carbonyl metalloimmunoassay (CMIA) is a heterogeneous competitive-type metalloimmunoassay using metal carbonyl complexes as tracers, organic solvents (ethyl acetate, isopropyl ether) to separate the free and bound fractions, and Fourier-transform infrared (FT-IR) spectroscopy for quantification. The choice of FT-IR... 

Finally, in this section, we should mention the complexing to immunoglobulins which enhances inhibition of DNA synthesis, not only of linked cisplatin but also for PtCl ", in comparison with the activity of the free compounds [82]. Again, the possibility exists of activating hitherto inactive or weakly active structures. The use of a metalloimmunoassay to target metal complexes is a novel approach which has also been described [83, 84]. 

Metalloimmunoassays for proteins based on stripping analysis of copper- and silver-enhanced " AuNPs as well as silver nanoparticle labels have also been reported. One problem with all dissolution-based strategies for electrochanical detection of nanoparticle or enhanced nanoparticle labels is that dissolution often involves anploying toxic or corrosive reagents, for example, hydrobromic acid/bromine mixture for AuNPs and nitric acid for silver nanoparticles and copper- or silver-enhanced AuNPs. In one study, electrooxidation and complexation with thiocyanate was used as an alternative to dissolve silver nanoparticles in place of nitric acid for anodic stripping detection of myoglobin. ... 

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