ИСТИНА

Introduction A large family of ambient MS methods is based directly on electrospray ionization from the sample-containing tip or even from the solid sample itself. Paper-spray ionization is a well-known method that allows fast and simple analysis of biological liquids and extracts in combination with substantially improved sample handling and storage. Numerous techniques originate from this concept, including direct electrospray probe (DEP) and touch spray (TS) ionization from metal or wooden tips. In this work, we demonstrate the implementation of porous polypropylene marker tips as a sampling device as well as ionization tip for ambient mass spectrometry approach. Methods Prewashed marker tips made from polypropylene were used for sampling by dripping of liquid sample or touching to the analyzed surface or skin. Tips were mounted into the in-lab ion source, and solvent flow and high voltage were applied. Spectra were recorded on Thermo LTQ XL Orbitrap mass spectrometer. Preliminary Data Porous polypropylene marker tip combines advantages of high absorption, simplicity of manipulation, and low cost due to mass production. The internal structure of the tip is very penetrable for solvent so that analytes could be easily washed and ionized. Application of marker tips leads to significantly improved stability and reproducibility of spectra as solvent could uniformly flow through the tip. That leads to the formation of a single and very stable Taylor cone similar to obtained using metal or glass capillary. Compared to many other ambient mass spectrometry techniques, porous polypropylene marker tips make the total ion current more stable due to a very smooth surface on the submillimeter level. Novel Aspect The advantages of the implementation of porous polypropylene marker tips to ambient mass spectrometry were demonstrated.