Gold complexes labelled

This section discusses the properties of gold particles as well as the common methods of labeling proteins and other biomolecules with them. The cited references should be consulted to obtain protocols for using these protein-gold complexes in assay and detection systems. 

In other words, the gold complex is of formal MX type. Thus, the NBO description of the bonding goes considerably beyond the hapticity labels in (4.110) and suggests that only a severely distorted and reorganized form of the allyl anion exists in either of these complexes. 

Roth, J. (1982) The preparation of protein A-gold complexes with 3 nm and 15 nm gold particles and their use in labeling multiple antigens on ultra-thin sections. Histochem. J. 14,791-801. 

One of the approaches is to use colloidal gold as label [29] in electrochemical immunoassay. In addition to standard stages of the immune complex formation, oxidative release of gold and removal of excessive bromine are included into the analysis procedure. 

Louro, D. and Lesemann, D. E. (1984) Use of protein A-gold complex for specific labelling of antibodies bound to plant viruses. J. Virol. Methods 9, 107-122. 

There are also two smaller reduction waves at more positive potentials. Similar cyclic voltammograms displaying three cathodic reduction peaks and two anodic oxidation peaks were obtained for the other complexes in this series. The main reduction peak for each gold complex is similar to the peak obtained from the polarographic study (see Table 4, values labeled c). The nonintegral n values and the complex CVs were attributed to dissociation of the dithiocarbamate ligand upon reduction of Aum(dtc)3 to [Au ldtchl2, followed by reaction of free dtc with the mercury electrode (see Scheme 1). 

Vernooy-Gerritsen, M. J.L.M. Leuinssen G.A. Veldink J.F.G. Vliegenthart. Intracellular localization of lipoxygenases-1 and -2 in germinating soybean seeds by indirect labeling with protein a-colloidal gold complexes. Plant Physiol. 1984, 76, 1070-1079. 

The gold-195-labelled gold-dppe complex, 50c (SK F[ Au] 104524), has been obtained using chloro[ Au]auric acid (equation 57). The labelled product, 50c, was diluted with unlabelled material. Radiogold Au was produced in Pt(p,n) Au nuclear reaction. 

Yang, Y.-S., Datta, A., Hainfeld, J. F., Furuya, F. R., Wall, J. S., and Frey, P. A. (1994). Mapping the lipoyl groups of the pyruvate dehydrogenase complex by use of gold cluster-labels and scanning transmission electron microscopy. Biochemistry 33, 9428-9437. 

The electroactive labels most used in genosensing design are ferrocene and its derivates [24-27] (the reversible oxidation process of ferrocene can be detected by means of several electrochemical techniques), osmium complexes [28], platinum complexes [29], gold complexes [30, 31], and metallic [32-36] or semiconductor nanoparticles [37]. Among the last ones, gold nanoparticles are the most used, their detection can be carried out by means of the measurement of resistance or capacitance changes, usually after an amplification procedure with silver, or by means of the anodic stripping voltammetry of Au(lll) obtained after the nanoparticle oxidation Fig. 9.3. 

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