Biology subjects

Zubkovs, V.

Publications and source records attributed to Zubkovs, V..

2 recordsLinked to original sources

bioRxiv2024

Covalent conjugation of glucose oxidase on single-walled carbon nanotubes for glucose sensing

Glucose sensing and monitoring are crucial for biological and medical applications. Compared to existing methods, real-time detection and long-term monitoring are still required. Single-walled carbon nanotubes (SWCNTs) have excellent optical properties for sensing applications, which provide the possibility for designing a new generation of glucose sensors. In this study, we describe a method for covalently conjugate glucose oxidase (GOx) on SWCNTs as an optical glucose sensor. The functional groups are introduced by a photocatalytic reaction which acts as the handle for protein loading on SWCNTs. In this sp3 defect reaction, the optical properties of SWCNTs can be maintained. With a convenient bioconjugation reaction, the GOx could be covalently linked with SWCNTs. Compared to the non-covalent immobilization conjugates, the covalent conjugate sensor exhibits a much stronger optical response toward glucose, and the stability of the biosensor also increases in harsh conditions. At the same time, we also report the changing ratio of the original E11 and defected E11* peak during the bioconjugation reaction, which is also inspiring for reaction monitoring on SWCNTs. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=75 SRC="FIGDIR/small/618143v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@e1ef8org.highwire.dtl.DTLVardef@11354d7org.highwire.dtl.DTLVardef@2717cforg.highwire.dtl.DTLVardef@8c57bd_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2021

A simple micropreparative gel electrophoresis technique for purification of proteins, nucleic acids, and bioconjugates

The biochemical and biomedical fields hinge on the ability to effectively separate and purify biological macromolecules. Though this need is largely addressed with a variety of chromatographic and electrophoretic purification techniques, such techniques are usually laborious, time-consuming, and often require complex and costly instalments that are inaccessible to most laboratories. In this work, we introduce a simple micro-preparative (MP) method based on polyacrylamide gel electrophoresis (PAGE) to purify biological samples containing proteins, nucleic acids, and complex bioconjugates. Using a conventional vertical slab system, we demonstrate the extraction of purified DNA, proteins, and DNA-protein bioconjugates from their respective mixtures using MP-PAGE. We apply this system to recover DNA from a ladder mixture with yields of up to 90%, compared to the 58% yield obtained using specialized commercial devices. We also demonstrate the purification of folded enhanced yellow fluorescence protein (EYFP) from crude cell extract with 90% purity, comparable to purities achieved using a two-step size exclusion and immobilized metal-ion affinity chromatography purification procedure. Finally, we demonstrate the successful isolation of an EYFP-DNA bioconjugate sample that otherwise could not be processed using the two-step chromatography procedure. MP-PAGE thus offers a rapid and versatile means of purifying a variety of biomolecules without the need for specialized equipment.

biochemistry↗