Convenient Graphical Visualization of Messages Encoded in Sequence-Defined Synthetic Polymers Using Kendrick Mass Defect Analysis of their MS/MS Data
Abstract
Kendrick mass defect (KMD) analysis is shown here to be a convenient method to read binary messages encoded in the structure of two types of sequence-defined synthetic polymers, namely, polyurethanes and poly(alkoxyamine phosphodiester)s. KMD analysis allows graphical ranking of mass data obtained for species containing repeating units. This is performed on MS/MS data in which distribution of fragments reveals the comonomer sequence of digital macromolecules. Choosing one coding monomer as the base unit, KMD computation of MS/MS data leads to stair-like plots where flat steps correspond to that monomer selected as the base unit while oblique steps reveal the other monomer. To correct for any point misalignments resulting from slight inaccuracy of fragment mass measurement, fractional base units are used to perform resolution-enhanced KMD (RE-KMD) analysis. As the length of the chain increased, a procedure aiming at correct aliased points is also implemented to achieve continuous, more convenient, stair-like plots.