Gold-labelled lectins

Carbohydrates were cy to chemically detected in hydrogenosome membranes using the periodic acid-thiosemicarbazide-silver proteinate technique (Fig. 6a) and gold-labeled lectins, such as WGA (Fig. 6b) (Benchimol... 

Schmidt, J. Peters, W. (1987). Localization of glycoconjugates at the tegument of the tapeworms Hymenolepis nana and H. microstoma with gold labelled lectins. Parasitology Research, 73 80-6. 

Figure 6.15. Gold-labelled lectin binding to a SAM which is -functionalized with glucose. The gold-labelled Con-canavalin A adsorbed on to the 10 gm diameter circles of glucose containing the SAM (adapted from ref. (40))...

Roth, J., and Binder, M. (1978) Colloidal gold, ferritin, and peroxidase as markers for electron microscopic double labeling lectin techniques./. Histochem. Cytochem. 26, 163. 

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). 

The following generalized protocol is an adaptation for the labeling of 15 nm gold particles with Aplysia gonad lectin, as described by Benhamou et al., 1988. Each lectin-gold preparation will have its own unique pH optimum and ratio of lectin-to-gold for the absorption process. 

Horisberger, M., Rosset, J. and Vonlanthen, M. 1977. Location of glycoproteins on milk fat globule membrane by scanning and transmission electron microscopy, using lectin-labelled gold granules. Exp. Cell Res. 109, 361-369. 

Lectin Purified lectin Fluoro- chrome labeled Biotin or hapten labeled Protein conjugated Gold conjugated Immobilized... 

The up-to-date trends in using colloidal-gold markers for bioanalytical studies are as follows (i) to minimize the analyte substance amount (antigens, oligonucleotides, lectins, etc.) and (ii) to enhance the sensitivity of analysis. For instance, a sensitivity up to 60-70 ng L" has been reported [104] for an assay based on a simple replacing of the nitrocellulose membranes by microarrays combined with a photometrical reader. 11 should be emphasized that the microarray assay utilizes microliter volumes both for analyte probes and for labeled markers. Besides, the photometrical reader, together with the accessory equipment, allows for 384 probes to be analyzed within a short time period. 

Colloidal gold, ferritin, and peroxidase have been used as electron markers in the double labelling of a number of lectin-binding sites. ... 

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