An extensive characterization of pristine and oxidized TiCT (T: =O, -OH, -F) MXene showed that exposure of MXene to an anodic potential in the aqueous solution oxidizes the nanomaterial forming TiO layer or TiO domains with subsequent TiO dissolution by F ions, making the resulting nanomaterial less electrochemically active compared to the pristine TiCT. The TiCT could be thus applied for electrochemical reactions in a cathodic potential window i.e. for ultrasensitive detection of HO down to nM level with a response time of approx. 10 s. The manuscript also shows electrochemical behavior of TiCT modified electrode towards oxidation of NADH and towards oxygen reduction reactions.

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Impedimetric lectin biosensors capable of recognizing two different carbohydrates (galactose and sialic acid) in glycans attached to antibodies isolated from human serum were prepared. The first step entailed the modification of a gold surface by a self-assembled monolayer (SAM) deposited from a solution containing a carboxybetaine-terminated thiol applied to the subsequent covalent immobilization of lectins and to resist nonspecific protein adsorption. In the next step, Sambucus nigra agglutinin (SNA) or Ricinus communis agglutinin (RCA) was covalently attached to the SAM, and the whole process of building a bioreceptive layer was optimized and characterized using a diverse range of techniques including electrochemical impedance spectroscopy, cyclic voltammetry, quartz crystal microbalance, contact angle measurements, zeta-potential assays, X-ray photoelectron spectroscopy, and atomic force microscopy. In addition, the application of the SNA-based lectin biosensor in the glycoprofiling of antibodies isolated from the human sera of healthy individuals and of patients suffering from rheumatoid arthritis (RA) was successfully validated using an SNA-based lectin microarray. The results showed that the SNA lectin, in particular, is capable of discriminating between the antibodies isolated from healthy individuals and those from RA patients based on changes in the amount of sialic acid present in the antibodies. In addition, the results obtained by the application of RCA and SNA biosensors indicate that the abundance of galactose and sialic acid in antibodies isolated from healthy individuals is age-related.

Viable microbial cells are important biocatalysts in the production of fine chemicals and biofuels, in environmental applications and also in emerging applications such as biosensors or medicine. Their increasing significance is driven mainly by the intensive development of high performance recombinant strains supplying multienzyme cascade reaction pathways, and by advances in preservation of the native state and stability of whole-cell biocatalysts throughout their application. In many cases, the stability and performance of whole-cell biocatalysts can be highly improved by controlled immobilization techniques. This review summarizes the current progress in the development of immobilized whole-cell biocatalysts, the immobilization methods as well as in the bioreaction engineering aspects and economical aspects of their biocatalytic applications.

This review comprehensively covers the most recent achievements (from 2013) in the successful integration of nanomaterials in the field of glycomics. The first part of the paper addresses the beneficial properties of nanomaterials for the construction of biosensors, bioanalytical devices, and protocols for the detection of various analytes, including viruses and whole cells, together with their key characteristics. The second part of the review focuses on the application of nanomaterials integrated with glycans for various biomedical applications, that is, vaccines against viral and bacterial infections and cancer cells, as therapeutic agents, for in vivo imaging and nuclear magnetic resonance imaging, and for selective drug delivery. The final part of the review describes various ways in which glycan enrichment can be effectively done using nanomaterials, molecularly imprinted polymers with polymer thickness controlled at the nanoscale, with a subsequent analysis of glycans by mass spectrometry. A short section describing an active glycoprofiling by microengines (microrockets) is covered as well.

A simple fabrication method for preparation of surfaces able to switch from superhydrophobic to superhydrophilic state in a reversible and fast way is described. A self-assembled monolayer (SAM) consisting of quaternary ammonium group with aliphatic tail bearing terminal thiol functionality was created on gold nano/microstructured and gold planar surfaces, respectively. A rough nano/microstructured surface was prepared by galvanic reaction on a silicon wafer. The reversible counterion exchange on the rough surface resulted in a switchable contact angle between <5° and 151°. The prewetted rough surface with Cl(-) as a counterion possesses a superoleophobic underwater character. The kinetics of counterion exchanges suggests a long hydration process and strong electron ion pairing between quaternary ammonium group and perfluorooctanoate counterion. Moreover, a wettability gradient from superhydrophobic to superhydrophilic can be formed on the modified rough gold surface in a robust and simple way by passive incubation of the substrate in a counterion solution and controlled by ionic strength. Furthermore, adsorption of gold nanoparticles to modified plain gold surface can be controlled to a high extent by counterions present on the SAM layer.

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