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A two-phase anion-exchange membrane was prepared from quaternized chitosan (QCS) integrated with an electrospun polyacrylonitrile (PAN) scaffold by spin coating. To synthesize QCS, glycidyltrimethylammonium chloride in various amounts was introduced into the structure of CS. The characterization of the cast cross-linked QCS (CQCS) membranes by impedance spectroscopy revealed the ionic conductivity (IC) in the range of 2.8 × 10–4 to 8.2 × 10–4 S cm–1 and the degree of quaternization (DQ) of 26.4–51.0%, where the CQCS film with the DQ of 51.0% showed excellent performance. When CQCS was reinforced with a PAN fiber mat, the newly developed composite membrane demonstrated the highest IC of 34 × 10–4 S cm–1 at 80 °C, low swelling, and an almost eightfold increase in tensile strength at a fully hydrated state compared to pristine materials. Moreover, the CQCS/PAN membrane was chemically stable and revealed increasing hydroxide transport during 1 month immersion in alkaline media.

Визуализация биологических объектов в естественных средах в движении с высокой разрешающей способностью, не нарушая их функций – крайне сложная задача. Исследования последних лет подтверждают, что динамическая структура и морфология белков и клеток, выявленные с помощью быстродействующего СЗМ, дают уникальную информацию о том, как функционируют клеточные процессы на молекулярном уровне.