A new type of encoded bead, which uses surface-enhanced Raman scattering (SERS), is described for multiplex immunoassays. Silver nanoparticles were embedded in sulfonated polystyrene (PS) beads via a polyol method, and they were used as SERS-active substrates. Raman-label organic compounds such as 4-methylbenzenethiol (4-MT), 2-naphthalenethiol (2-NT), and benzenethiol (BT) were then adsorbed onto the silver nanoparticles in the sulfonated PS bead. Although only three kinds of encoding have been demonstrated here, various combinations of these Raman-label organic compounds have the potential to give a large number of tags. The Raman-label-incorporated particles were then coated with a silica shell using tetraethoxyorthosilicate (TEOS) for chemical stability and biocompatibility. The resulting beads showed unique and intense Raman signals for the labeled organic compounds. We demonstrated that SERS-encoded beads could be used for multiplex detection with a model using streptavidin and p53. In our system, the binding event of target molecules and the type of ligand can be simultaneously recognized by Raman spectroscopy using a single laser-line excitation (514.5 nm).

Twenty two kojic acid–tripeptide amides were prepared using a solid‐phase Fmoc/tBu strategy with Rink Amide SURE® resin. To effectively obtain kojic acid–tripeptide amide conjugates, the coupling conditions of kojic acid to the tripeptide on the resin were optimized. The tyrosinase inhibitory activity of kojic acid–tripeptide amides and the effect of the amino acid sequence on the activity were compared with those of kojic acid–tripeptide acids. The stability of kojic acid–tripeptide amides were then compared with those of kojic acid and kojic acid–tripeptides acids. As a consequence, kojic acid‐FWY‐NH2 proved to be the best compound, with the highest inhibitory activity, which was maintained over different storage times under various temperatures and pHs. © 2007 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 88: 300–307, 2007. This article was originally published online as an accepted preprint. The ‘Published Online’ date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com

No abstract

5-Hydroxymethyl-2-furaldehyde (HMF) was hydrogenated to 2,5-bis(hydroxymethyl)furan (BHMF) (>99% yield) in various n-alcohol solvents using a Ru(OH)x/ZrO2 catalyst.