METHOD TO PRODUCE REMOVABLE WATER-INSOLUBLE ION-EXCHANGE COATINGS ON MALDI TARGETS AND THEIR APPLICATION FOR MASS-SPECTROMETRIC ANALYSIS

摘要

FIELD: biotechnologies.;SUBSTANCE: method is proposed to produce removable water-insoluble ion-exchange coatings on standard steel MALDI targets, and also on steel, glass, ceramic or plastic inserts into a MALDI target, compatible with performance of the further MALDI analysis. The surface of the MALDI target is coated with a water-organic solution of an ionogenic polymer and nitrocellulose and then dried, at the same time after usage such coatings are removed with water-alcohol solutions. Also the method is proposed to increase sensitivity of MALDI MS analysis of oligonucleotides using the produced coating. Water solutions containing oligonucleotides are applied into prepared surfaces. After several seconds the supernatant is removed, and the surface is washed with water or a dissolved water ammonia buffer. On the same points they apply the MALDI matrix, into solution of which the previously immobilised oligonucleotides transfer. After drying of the MALDI matrix the analysis is performed from the same substrate. The method makes it possible to produce DNA-binding surfaces, with an easily removed disposable water-insoluble surface film.;EFFECT: using such coating makes it possible to simplify the stage of removal of admixtures that interfere with MALDI MS analysis and to increase its speed and sensitivity.;2 cl, 4 dwg, 5 ex