periodate oxidation
Recently Published Documents


TOTAL DOCUMENTS

870
(FIVE YEARS 46)

H-INDEX

58
(FIVE YEARS 4)

2021 ◽  
Vol 22 (23) ◽  
pp. 12845
Author(s):  
Ksenia A. Sapozhnikova ◽  
Vsevolod A. Misyurin ◽  
Dmitry Y. Ryazantsev ◽  
Egor A. Kokin ◽  
Yulia P. Finashutina ◽  
...  

Bioconjugation of antibodies with various payloads has diverse applications across various fields, including drug delivery and targeted imaging techniques. Fluorescent immunoconjugates provide a promising tool for cancer diagnostics due to their high brightness, specificity, stability and target affinity. Fluorescent antibodies are widely used in flow cytometry for fast and sensitive identification and collection of cells expressing the target surface antigen. Nonetheless, current approaches to fluorescent labeling of antibodies most often use random modification, along with a few rather sophisticated site-specific techniques. The aim of our work was to develop a procedure for fluorescent labeling of immunoglobulin G via periodate oxidation of antibody glycans, followed by oxime ligation with fluorescent oxyamines. Here, we report a novel technique based on an in situ oxime ligation of ethoxyethylidene-protected aminooxy compounds with oxidized antibody glycans. The approach is suitable for easy modification of any immunoglobulin G, while ensuring that antigen-binding domains remain intact, thus revealing various possibilities for fluorescent probe design. The technique was used to label an antibody to PRAME, a cancer-testis protein overexpressed in a number of cancers. A 6H8 monoclonal antibody to the PRAME protein was directly modified with protected-oxyamine derivatives of fluorescein-type dyes (FAM, Alexa488, BDP-FL); the stoichiometry of the resulting conjugates was characterized spectroscopically. The immunofluorescent conjugates obtained were applied to the analysis of bone marrow samples from patients with oncohematological diseases and demonstrated high efficiency in flow cytometry quantification. The approach can be applied for the development of various immunofluorescent probes for detection of diagnostic and prognostic markers, which can be useful in anticancer therapy.


Author(s):  
Sawsan Dacrory ◽  
Samir Kamel ◽  
G. M. Turky

Abstract Cellulose has attracted much attention as a potential substrate for low-cost, flexible electronics. Here, new cellulose-based films embedded with nano-silver (AgNs) and carbon (C) were successfully prepared. First, cellulose was oxidized to tricarboxy cellulose (TCC) using 2,2,6,6 tetramethylpiperidine-1-oxyl followed by periodate oxidation. Then, nano-silver was prepared by polyol method and carbon was prepared via a single-step from bagasse. The structure, thermal, morphology, mechanical properties, and broad-band were characterized by infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy with energy-dispersive X-ray, X-ray diffraction, and stress-strain relation. The results showed that the tensile strength and thermal stability of the films were improved. The temperature dependence of permittivity,  of the TCC film, increased in two trends. However, TCC film shows non-conducting features, especially at lower temperatures; its nanocomposites films show a semiconducting behavior, and its ac-conductivity follows the empirical Jonscher law. Although the temperature dependence of dc-conductivity of the TCC/C, shows an Arrhenius behavior with low activation energy (≈ 3.74 kJ/mol.), its investigated nanocomposites follow the well-known Vogel Fulcher Tamman equation according to the fragility of the prepared samples and/or the correlation between the interfacial polarization and conductivity.


Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3875
Author(s):  
Marija D. Stanišić ◽  
Nikolina Popović Kokar ◽  
Predrag Ristić ◽  
Ana Marija Balaž ◽  
Milan Senćanski ◽  
...  

Zeolitic imidazolate framework-8 (ZIF-8) is widely used as a protective coating to encapsulate proteins via biomimetic mineralization. The formation of nucleation centers and further biocomposite crystal growth is entirely governed by the pure electrostatic interactions between the protein’s surface and the positively charged Zn(II) metal ions. It was previously shown that enhancing these electrostatic interactions by a chemical modification of surface amino acid residues can lead to a rapid biocomposite crystal formation. However, a chemical modification of carbohydrate components by periodate oxidation for glycoproteins can serve as an alternative strategy. In the present study, an industrially important enzyme glucose oxidase (GOx) was selected as a model system. Periodate oxidation of GOx by 2.5 mM sodium periodate increased negative charge on the enzyme molecule, from −10.2 to −36.9 mV, as shown by zeta potential measurements and native PAGE electrophoresis. Biomineralization experiments with oxidized GOx resulted in higher specific activity, effectiveness factor, and higher thermostability of the ZIF-8 biocomposites. Periodate oxidation of carbohydrate components for glycoproteins can serve as a facile and general method for facilitating the biomimetic mineralization of other industrially relevant glycoproteins.


Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3442
Author(s):  
Maxime Sorriaux ◽  
Mathias Sorieul ◽  
Yi Chen

Water contamination resulting from human activities leads to the deterioration of aquatic ecosystems. This restrains the access to fresh water, which is the leading cause of mortality worldwide. In this work, we developed a bio-based and water-resistant composite aerogel from renewable nanofibrils for water remediation application. The composite aerogel consists of two types of cross-linked nanofibrils. Poly(dopamine)-coated cellulose nanofibrils and amyloid protein nanofibrils are forming a double networked crosslinked via periodate oxidation. The resulting aerogel exhibits good mechanical strength and high pollutants adsorption capability. Removal of dyes (rhodamine blue, acriflavine, crystal violet, malachite green, acid fuchsin and methyl orange), organic traces (atrazine, bisphenol A, and ibuprofen) and heavy metal ions (Pb(II) and Cu(II)) from water was successfully demonstrated with the composite aerogel. More specifically, the bio-based aerogel demonstrated good adsorption efficiencies for crystal violet (93.1% in 30 min), bisphenol A (91.7% in 5 min) and Pb(II) ions (94.7% in 5 min), respectively. Furthermore, the adsorption–desorption performance of aerogel for Pb(II) ions demonstrates that the aerogel has a high reusability as maintains satisfactory removal performances. The results suggest that this type of robust and bio-based composite aerogel is a promising adsorbent to decontaminate water from a wide range of pollutants in a sustainable and efficient way.


Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5851
Author(s):  
Cong Gao ◽  
Shuo Wang ◽  
Baojie Liu ◽  
Shuangquan Yao ◽  
Yi Dai ◽  
...  

In this study, we incorporated 2,3-dialdehyde nanocrystalline cellulose (DANC) into chitosan as a reinforcing agent and manufactured biodegradable films with enhanced gas barrier properties. DANC generated via periodate oxidation of cellulose nanocrystal (CNC) was blended at various concentrations with chitosan, and bionanocomposite films were prepared via casting and characterized systematically. The results showed that DANC developed Schiff based bond with chitosan that improved its properties significantly. The addition of DANC dramatically improved the gas barrier performance of the composite film, with water vapor permeability (WVP) value decreasing from 62.94 g·mm·m−2·atm−1·day−1 to 27.97 g·mm·m−2·atm−1·day−1 and oxygen permeability (OP) value decreasing from 0.14 cm3·mm·m−2·day−1·atm−1 to 0.026 cm3·mm·m−2·day−1·atm−1. Meanwhile, the maximum decomposition temperature (Tdmax) of the film increased from 286 °C to 354 °C, and the tensile strength of the film was increased from 23.60 MPa to 41.12 MPa when incorporating 25 wt.% of DANC. In addition, the chitosan/DANC (75/25, wt/wt) films exhibited superior thermal stability, gas barrier, and mechanical strength compared to the chitosan/CNC (75/25, wt/wt) film. These results confirm that the DANC and chitosan induced films with improved gas barrier, mechanical, and thermal properties for possible use in film packaging.


Cellulose ◽  
2021 ◽  
Author(s):  
Saül Llàcer Navarro ◽  
Koyuru Nakayama ◽  
Alexander Idström ◽  
Lars Evenäs ◽  
Anna Ström ◽  
...  

AbstractPeriodate oxidation introduces aldehyde functionality to cellulose. The use of dialdehyde cellulose has been demonstrated for crosslinking and as a chemical intermediate towards functionalized cellulose. Commercially available cellulose nanocrystals (CNCs) typically carry a surface sulfate half-ester functionality, which results from their manufacture via sulfuric acid hydrolysis and subsequent esterification. The sulfate half-ester group is a bulky group carrying a net negative charge above pH 2 that modifies the colloidal and electro-chemical properties of the CNCs. Periodate oxidation is regioselective to the bond between carbons in positions 2 and 3 in the anhydroglucose unit while the sulfate half-ester groups are mostly considered to be located in carbon in position 6. This regioselectivity could be the reason why the role played by the sulfate half-ester group on modification by periodate oxidation has not previously been elucidated. Here, the influence of the sulfate half-ester on the oxidation of CNCs, which is shown to steer the oxidation kinetics and the properties of the resulting materials, is studied. Conventional physicochemical analysis of the oxidant consumption is accompanied by elemental analysis, Fourier-transform infrared, X-ray photoelectron and solid-state nuclear magnetic resonance spectroscopy, and wide-angle x-ray scattering analyses; the zeta potential is used to characterize the colloidal properties of the suspensions and atomic force microscopy for determining particle dimensions. The presence of the sulfate half-ester group decreases the rate of oxidation. However, the content of the sulfate half-ester groups decreases when degree of oxidation reaches approx. 50%. We demonstrate that the CNC surfaces are affected by the oxidation beyond the C2–C3 bond cleavage: insight into the kinetics of the oxidation process is a prerequisite for optimizing CNC oxidation.


2021 ◽  
pp. 2100058
Author(s):  
Ting Yang ◽  
Peiwen Liu ◽  
Dan Xu ◽  
Jiaxiu Wang ◽  
Kai Zhang

Sign in / Sign up

Export Citation Format

Share Document