Implementation of Receiving Antenna Using Mechanism of Electrokinetic Phenomenon "Flow Potential"

Abstract

Предложен способ модификации мишени для МАLDI-МS-анализа, позволяющий селективно выделять аналиты из биологических образцов непосредственно на поверхности мишени, как альтернатива классическим методам. Для модификации мишени суспензию металл-аффинного сорбента на основе оксида железа(III) в 50% водно-метанольном растворе электрораспыляли в бескапельном режиме c динамическим делением потока жидкости при атмосферном давлении в нормальных условиях. МАLDI-мишень выступала в качестве противоэлектрода. На МАLDI-мишень наносился слой сорбента в виде пятна, частицы которого в дальнейшем устойчивы к воздействию растворителей. На модифицированной МАLDI-мишени проводилось металл-аффинное обогащение фосфорилированного пептида с аминокислотной последовательностью SSNGHV(pY)EKLSSI из образца триптического гидролизата глобина человека. МАLDI-масс-спектр записывали с пятна сорбента. Такая методика создана в качестве альтернативы трудоемкой пробоподготовке биопроб и позволяет ограничиться минимальными объемами образца и растворителей.

Electrokinetic repeater of acoustic vibrations

“…The authors have earlier considered in [1,2] and other papers the acoustoelectric conversion based on such an electrokinetic phenomenon as electroosmosis. In [3] there was suggested an acoustoelectric conversion based on the electrokinetic phenomenon reverse to electroosmosis, i. e. flow potential that is sometimes referred to as current potential [4]. Analysis of studies [1][2][3] showed that in both the cases of direct and reverse conversion almost identical mathematical and physical models are applicable, which is caused by the conversion reversibility and, hence, by the reversibility of electrokinetic transducers.…”

“…is the external bulk force that is the source of the process of flow potential [3], η and ζ are the dynamic and bulk viscosities, respectively, ρ e is the electric charge density induced by the presence of a double layer in electrokinetic processes, ε is the dielectric permeability, ε 0 is the electric constant, ζ is the electrokinetic potential (zeta-potential), σ is the fluid conductivity. Index 0 corresponds to the electroosmosis process generated by the DC electric field E 0 , parameters without indices correspond to the remaining processes whose sources are the external acoustic field, flow potential, and also pump-induced fields.…”

“…We interpret F included in expression (7) as Coulomb force F = ρ e E, where E = E a + E ′ are the vectors of certain AC electric fields (see [3]),…”

“…Assume that the capillary axis is oriented along the Oz axis. Paper [3] has shown that under the assumption of a thin double layer κa ≫ 1 (a is the capillary radius, κ = 1/λ D , λ D is the double layer Debye length or thickness) the electroosmotic velocity is defined as v 0 = (0, 0, U eo ), U eo = E 0 εε 0 η ζ = const. Thus, v 0 = (0, 0, U eo ).…”

“…(ii) At the same " noise meter−loud speaker" geometry, a receiving matrix (electrokinetic acoustoelectric transducer [3]) was installed between the noise meter and acoustic columns in line with them. In this case, no pumping was supplied to the matrix.…”