Labeling with gold

FIGURE 14.1 Scanometric DNA array detection with enlarged nanoparticle probes. Use of oligonucleotide targets, labeled with gold nanoparticles, for recognizing DNA segments on a chip (reproduced from [13] with permission). 

Fig. 6 Carbohydrates in hydrogenosomes. Monocercomonas sp. after the Thiery technique (a). The hydrogenosomal membranes are positive for carbohydrates, b T. foetus cryosection labeled with gold-conjugated WGA. Hydrogenosome (H) shows that the membrane lining the peripheral vesicle, but not other portions of the organelle, is labeled. Bars = 100 nm. (Fig. 6a from Diniz and Benchimol 1998 Fig. 6b from Benchimol et al. 1996a)...

Tolsen, N. D., Boothroyd, B., and Hopkins, C. R. (1981) Cell-surface labelling with gold colloidal particles, the use of avidin and staphylococcal protein A-coated gold in conjunction with biotin and Fc-beanng ligands. J. Microsc 123,215—226. 

Lectins, or proteins with specific binding sites for carbohydrates, can be used as targeting molecules to localize particular glycoconjugates such as glycoproteins or glycolipids on cell surfaces (Fig. 373). Labeled with gold particles, lectins are important probes for detection of cell surface components and intracellular receptors and in immunological or biochemical assay procedures (Bog-Hansen et al., 1978 Kimura et al., 1979 Nicolson, 1978 Roth, 1983 Benhamou et al., 1988 Nakajima et al., 1988). 

Valera, E., J. Ramdn-Azcon, FJ. Sanchez, et al. 2008. Conductimetric immunosensor for atrazine detection based on antibodies labelled with gold nanoparticles. Sens. Actuat. It Chem. 134 95-103. 

A third class of labels for antibodies that can be used for bright filed microscopic immunocytochemistry is particulate labels. Antibodies can be labeled with gold... 

Accommodation of a homogeneous separation-free immunoassay on a dry matrix. This is possible for SLFIA and for ARIS. Other possibilities are labeling with gold particles or liposomes. The art lies in contact-free accommodation of all the reagents on the test strip, in such a way that no immune reaction takes place during storage. 

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