Site Distribution in Resin Beads as Determined by Confocal Raman Spectroscopy

✍ Scribed by Jürgen Kress; Abigail Rose; Jeremy G. Frey; William S. Brocklesby; Mark Ladlow; Geoff W. Mellor; Mark Bradley

• Book ID: 101372340
• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: English
• Weight: 103 KB
• Volume: 7
• Category: Article
• ISSN: 0947-6539
• DOI: 10.1002/1521-3765(20010917)7:18<3880::aid-chem3880>3.0.co;2-#

✦ Synopsis

Scanning confocal Raman spectroscopy was used to study the distribution of reactive sites within a resin bead used for solid-phase synthesis. The distribution of NH 2 groups in aminomethylated polystyrene resin (APS) was determined by doping with varying amounts of 4-cyanobenzoic acid. The extent of loading was determined by both elemental analysis and ninhydrin assays. The spatial distribution of the coupled 4-cyanobenzamide within the bead was determined to an in-plane resolution of 1 mm and depth resolution of about 4 mm, using the strong Raman CN stretching vibrational transition at 2230 cm À1 . Dry and swollen beads were studied and the distribution was found to be essentially uniform throughout the bead in all cases.