Gold crosslinked

Insoluble polystyrene crosslinked with divinylbenzene can easily be converted by sulfonation to a usable ion exchanger. For this purpose a mixture of 0.2 g of silver sulfate and 150 ml of concentrated sulfuric acid are heated to 80-90 °C in a 500 ml threenecked flask fitted with stirrer, reflux condenser, and thermometer. 20 g of a bead polymer of styrene and divinylbenzene (see Example 3-41) are then introduced with stirring the temperature climbs spontaneously to 100-105 °C.The mixture is maintained at 100 C for 3 h,then cooled to room temperature and allowed to stand for some hours. Next the contents of the flask are poured into a 11 conical flask that contains about 500 ml of 50% sulfuric acid. After cooling, the mixture is diluted with distilled water, and the gold-brown colored beads are filtered off on a sintered glass filter and washed copiously with water. 

Yang H, Lazos D, Ulbricht M. Thin, highly crosslinked polymer layer synthesized via photo-initiated graft copolymerization on a self-assembled-monolayer-coated gold surface. J Appl Polym Sci 2005 97 158-164. 

Most recently, we reported small molecule arrays on photoaffinity crosslinker coated gold surfaces (17). The small molecule arrays were fabricated by photoreaction, and then analyzed by SPR imaging technique. The small molecules don t have to be modified chemically for immobilization. The small molecules, which can interact with a target protein, can be screened by this methodology. Therefore, the integration of photoaffinity small molecule array and SPR imaging technique can be the first step of reverse chemical genetics. 

A photoaffinity crosslinker modified gold chip and 96-well microplate with 15 sugar solutions was placed in a contact pin type automated spotter. 

Saxton, T.M., Oostween, I., Bowtell, D., Aebersold R., and Gold, M.R., 1994, B cell antigen receptor crosslinking induces phosphorylation of the ras activators SHC and mSOSl as well as the assembly of complexes containing SHC, Grb2 and SOS1 and a 145 kDa tyrosine phosphorylated protein. J. Immunol. 153 623-636. 

Salsa, T. Pina, M.E. Teixeira-Dias, J.J.C. Crosslinking of gelatin in the reaction with formaldehyde an ftir spectroscopic study. Appl. Spectrosc. 1996, 50 (10), 1314—1318. Buice, R.G. Gold, T.B. Lodder, R.A. Digenis, G.A. Determination of moisture in intact gelatin capsules by near-infrared spectrophotometry. Pharm. Res. 1995,12 (1), 161-163. 

Gold TB, Buice RG Jr, Lodder RA, Digenis GA. Determination of extent of formaldehyde-induced crosslinking in hard gelatin capsules by near-infrared spectrophotometry. Pharm Res 1997 Aug 14(8) 1046-1050. 

NAD was covalently linked via a PQQ spacer to a gold electrode. This modified electrode is capable of binding LDH over the exposed nicotinamide groups. Upon oxidation of lactate to pyruvate the excess electrons tunnel from NADH in the active site to PQQ and eventually to the anode. Thus, a kind of electrical linkage between the enzyme and the electrode is established. The enzymes were crosslinked, as LDH is a homotetramer and might dissociate during the reaction. This approach is not only useful for electrochemical biosensors but might be transferred to other oxidoreductase reactions. 

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