110 research outputs found
High-density information storage in an absolutely defined aperiodic sequence of monodisperse copolyester
Synthesis of a polymer composed of a large discrete number of chemically distinct monomers in an absolutely defined aperiodic sequence remains a challenge in polymer chemistry. The synthesis has largely been limited to oligomers having a limited number of repeating units due to the difficulties associated with the step-by-step addition of individual monomers to achieve high molecular weights. Here we report the copolymers of ??-hydroxy acids, poly(phenyllactic-co-lactic acid) (PcL) built via the cross-convergent method from four dyads of monomers as constituent units. Our proposed method allows scalable synthesis of sequence-defined PcL in a minimal number of coupling steps from reagents in stoichiometric amounts. Digital information can be stored in an aperiodic sequence of PcL, which can be fully retrieved as binary code by mass spectrometry sequencing. The information storage density (bit/Da) of PcL is 50% higher than DNA, and the storage capacity of PcL can also be increased by adjusting the molecular weight (~38???kDa)
A mass spectrometry study of tirapazamine and its metabolites: Insights into the mechanism of metabolic transformations and the characterization of reaction intermediates
Estimation of gas-phase acidities of deoxyribonucleosides: An experimental and theoretical study
Determination of the gas-phase acidities of cysteine-polyalanine peptides using the extended kinetic method
Generation and characterization of ionic and neutral [HS-P-OH]+/· and S=P(OH)2+/· in the Gas Phase by Tandem Mass Spectrometry and Computational Chemistry
Generation and characterization of ionic and neutral P(OH)2+/. in the gas phase by tandem mass spectrometry and computational chemistry
Determination of the gas-phase acidity of methylthioacetic acid using the Cooks’ kinetic method
Direct analysis of liquid samples by desorption electrospray ionization-mass spectrometry (DESI-MS)
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