Using Magnetic Levitation To Distinguish Atomic-level Differences In Chemical Composition Of Polymers, And To Monitor Chemical Reactions Onsolid Supports

摘要

This communication describes a density-based method that uses magnetic levitation to monitor chemical reactions on solid supports, and to distinguish differences in chemical composition of polymers. Solid-supported chemistry is widely used to prepare peptides, nucleic acids, libraries of small molecules, and capturing reagents for affinity purification and protein target identification. Solid-phase chemistry has the inconvenient feature that there is no inexpensive and rapid method for monitoring the progress of reactions quantitatively on insoluble polymeric supports. The methods currently available can be segregated into two categories: (ⅰ) colorimetric tests for the presence or absence of certain functional groups and (ⅱ) instrumental techniques (e.g., infrared and ultraviolet spectroscopy) that identify functional groups or provide characteristic spectroscopic information (e.g., mass spectroscopy, ~1H NMR using a magic angle spinning probe, and ~(13)C NMR).rnColorimetric tests are rapid and provide qualitative information about conversion but are subject to artifacts arising from competing side reactions (false positives) and incomplete reactions (false negatives). Spectroscopic instruments are substantially more informative than colorimetric tests, but they are expensive (>$10,000), usually time-consuming, and inconvenient to use, since they often must be shared by multiple users.