Isoelectric Point Determination of Proteins Using Track-Etched Single-Nanopore Membrane

Year 2016, Volume: 44 Issue: 4, 401 - 407, 01.11.2016

Kaan Keçeci

Abstract

In this study, we have investigated a new method to determine the pI values of proteins compared to the conventional methods. We developed a new sensing platform and paradigm to succeed it. The track-etched poly ethylene terephthalate PET membranes were used to fabricate both single and multipore membranes. Two-step chemical etching method was prefered to fabricate single nanopore in a reproducible manner. EDC-coupling was used to modify and attach the proteins inside the nanopore surface. By the aid of ion current rectification, the surface charge characteristics of nanopores were identified with and without protein. A close approximation was successfully made to the literature values for the pI values of proteins using nanopore membranes respect.

Keywords

Track-etched polymer membrane, ion-current rectification, nanopore sensor, electrochemical sensor

İz-Aşındırılmış Tekli Nano Membran Kullanarak Proteinlerin İzoelektrik Noktalarının Belirlenmesi

Abstract

B u çalışmada geleneksel yöntemlere kıyasla proteinlerin pI değerlerinin belirlenmesi için yeni bir yöntem geliştirilmesini araştırdık. Tekli ve çoklu nanogözeneklerin üretilmesi için iz-aşındırılmış polietilen tereftalat membranlar kullanılmıştır. Tekli nanogözeneklerin tekrarlanabilir şekilde üretilmesi için iki basamaklı kimyasal aşındırma yöntemi tercih edilmiştir. Nanogözeneklerin iç yüzeyine proteinlerin tutturulması için EDC bağlanması kullanılmıştır. İyon-akım rektifikasyonun yardımıyla protein varlığında ve yokluğunda yüzey yük karakteristiği belirlenmiştir. Nanogözenek membranlar kullanarak elde edilen veriler ile literatürde ki pI değerlerine başarı ile yaklaşılmıştır

Keywords

İz-aşındırılmış polimer membran, iyon-akım rektifikasyonu, nanogözenek sensörü, elektrokimyasal sensör

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