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Ultrasensitive impedimetric lectin biosensors recognising different glycan entities on serum glycoproteins were constructed. Lectins were immobilised on novel mixed self-assembled monolayer containing 11-mercaptoundecanoic acid for covalent immobilisation of lectins and betaine terminated thiol to resist non-specific interactions. Construction of biosensors based on Concanavalin A (Con A), Sambucus nigra agglutinin type I (SNA) and Ricinus communis agglutinin (RCA) on polycrystalline gold electrodes was optimised and characterised with a battery of tools including electrochemical impedance spectroscopy, various electrochemical techniques, QCM, FTIR spectroscopy, AFM, XPS and compared with a protein/lectin microarray. The lectin biosensors were able to detect glycoproteins from 1 fM (Con A), 10 fM (RCA) or 100 fM (SNA) with a linear range spanning 6 (SNA), 7 (RCA) or 8 (Con A) orders of magnitude. Furthermore, a detection limit for the Con A biosensor down to 1 aM was achieved in a sandwich configuration. A non-specific binding of proteins for the Con A biosensor was only 6.1% (probed with an oxidised invertase) of the signal towards its analyte invertase and a negligible non-specific interaction of the Con A biosensor was observed in diluted human sera (1000x), as well. The performance of the lectin biosensors was finally tested by glycoprofiling of human serum samples from healthy individuals and those having rheumatoid arthritis, which resulted in distinct glycan pattern between these two groups.

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Polyamide 6 (PA6)/multi‐walled carbon nanotubes (MWCNT) nanocomposites were produced by diluting a masterbach containing 20 wt % nanotubes using melt mixing. The influence of the addition of well dispersed MWCNT (as indicated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM)) on the thermal transitions, and crystallization behavior of the PA6 matrix is investigated. Differential scanning calorimetry (DSC) results show a reduction in heat capacity jump at the glass transition which is interpreted by an immobilized interfacial layer near the nanotubes. Furthermore, both DSC and X‐ray diffraction (XRD) measurements indicate that nanotubes favor the formation of the α crystalline form of PA6. These findings are correlated with the observed improvement of the storage modulus as revealed by dynamic mechanical thermal analysis (DMTA). Additionally, a new crystallization peak appears when MWCNT are added, and is attributed to the formation of a different morphology of the same type crystallite around the nanotubes walls (trans‐crystallinity). Finally, water sorption measurements show an increase of water content, normalized to the amorphous polymer fraction, in the nanocomposites. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 764–774, 2009

Nanocarbons represented especially by carbon nanotubes (CNTs) and graphene have been of great interest during the last two decades, both from a fundamental point of view and for future applications. The most eye-catching features of carbon nanostructures (CNSs) are their electronic, mechanical, optical and chemical characteristics, which open a way for versatile applications. Among those future prospects, actuators are one of the promising technologies. Since 1999 when the first macroscopic actuator containing CNTs was reported, the interest of utilizing these materials as well as other CNSs in active systems has been triggered all over the world. This paper gives a thorough review as well as in-depth descriptions of the many aspects of nanocarbon-based actuators. The review covers aspects of worldwide research and development of nanocarbon ionic actuators up to 2012. Materials which are covered by this review include CNTs and their composites, carbon nanofibres (CNFs), graphene and its derivatives, microporous carbon materials (for example carbide derived carbons (CDCs) and carbon aerogels) as well as the possible combinations of these materials. The considered aspects cover the following fields: synthesis and characterization of the investigated materials, the actuation mechanism as well as modelling and simulation. Applications comprising system integration and device development are also reviewed within this paper.

Inimitable properties of carbon quantum dots as well as a cheap production contribute to their possible application in biomedicine especially as antibacterial and antibiofouling coatings. Fluorescent hydrophobic carbon quantum dots are synthesized by bottom-up condensation method and used for deposition of uniform and homogeneous Langmuir−Blodgett thin films on different substrates. It is found that this kind of quantum dots generates singlet oxygen under blue light irradiation. Antibacterial and antibiofouling testing on four different bacteria strains (Escherichia coli, Staphylococcus aureus, Bacillus cereus, and Pseudomonas aeruginosa) reveals enhanced antibacterial and antibiofouling activity of hydrophobic carbon dots thin films under blue light irradiation. Moreover, hydrophobic quantum dots show noncytotoxic effect on mouse fibroblast cell line. These properties enable potential usage of hydrophobic carbon quantum dots thin films as excellent antibacterial and antibiofouling coatings for different biomedical applications.

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