Functionalization of Carbon Nanotubes with Well-Defined Functional Polymers via Thiol-Coupling Reaction

Thiolated Nanoparticles for Biomedical Applications: Mimicking the Workhorses of Our Body

Advances in nanotechnology have generated a broad range of nanoparticles (NPs) for numerous biomedical applications. Among the various properties of NPs are functionalities being related to thiol substructures. Numerous biological processes that are mediated by cysteine or cystine subunits of proteins representing the workhorses of the bodies can be transferred to NPs. This review focuses on the interface between thiol chemistry and NPs. Pros and cons of different techniques for thiolation of NPs are discussed. Furthermore, the various functionalities gained by thiolation are highlighted. These include overall bio- and mucoadhesive, cellular uptake enhancing, and permeation enhancing properties. Drugs being either covalently attached to thiolated NPs via disulfide bonds or being entrapped in thiolated polymeric NPs that are stabilized via inter- and intrachain crosslinking can be released at the diseased tissue or in target cells under reducing conditions. Moreover, drugs, targeting ligands, biological analytes, and enzymes bearing thiol substructures can be immobilized on noble metal NPs and quantum dots for therapeutic, theranostic, diagnostic, biosensing, and analytical reasons. Within this review a concise summary and analysis of the current knowledge, future directions, and potential clinical use of thiolated NPs are provided.

Synthesis of diverse α,ω-telechelic polystyrenes with di- and tri-functionality via tandem or one-pot strategies combining aminolysis of RAFT-polystyrene and a thiol–ene “click” reaction

Diverse new α,ω-telechelic polystyrenes with di-/tri-functionality were synthesized via tandem/one-pot strategies combining aminolysis of RAFT-polystyrene and a thiol–ene “click” reaction.

Simple and highly efficient direct thiolation of the surface of carbon nanotubes

We proposed a simple and high efficiency method for direct thiolation on the surface of the carbon nanotubes.

Carbon nanotubes linked with pitavastatin: synthesis and characterisation

The paper presents a study on functionalisation of multi-walled carbon nanotubes in the area of lattice defects and an attempt to bind the nanotubes with pitavastatin. Carbon nanotubes were synthesised by alcohol-chemical vapour deposition in the presence of the catalyst Fe-Co/MgO. The nanotubes were purified and the product was subjected to chemical functionalisation. Functional groups were introduced in the reaction of the purified nanotubes with thionyl chloride to obtain acidic chlorides linked to pitavastatin. The properties and structure of the nanotubes were analysed by FT-IR and Raman spectroscopies, transmission electron microscopy and liquid chromatography coupled with mass spectrometry. Photochemical stability of pitavastatin linked with carbon nanotubes has been found to be increased.

Surface modification of carbon nanotubes with dendrimers or hyperbranched polymers

The different methods for modification of carbon nanotubes with dendrimers or hyperbranched polymers are summarized, and recent development is highlighted by discussing some representative examples in detail.

Polymer/Carbon Nanotube Composites

The unique geometry and extraordinary mechanical, electrical, and thermal conductivity properties of carbon nanotubes (CNTs) make them ideal candidates as functional fillers for polymeric materials. In this paper we review the advances in both thermoset and thermoplastic CNT composites. The various processing methods used in polymer/CNT composite preparation; solution mixing, in-situ polymerization, electrospinning, and melt blending, are discussed. The role of surface functionalization, including ‘grafting to’ and ‘grafting from’ using atom transfer radical polymerization (ATRP), radical addition–fragmentation chain transfer polymerization (RAFT), and ring-opening metathesis polymerization (ROMP) in aiding dispersion of CNTs in polymers and interfacial stress transfer is highlighted. In addition the effect of CNT type, loading, functionality and alignment on electrical and rheological percolation is summarized. We also demonstrate the effectiveness of both Raman spectroscopy and oscillatory plate rheology as tools to characterize the extent of dispersion of CNTs in polymer matrices. We conclude by briefly discussing the potential applications of polymer/CNT composites and highlight the challenges that remain so that the unique properties of CNTs can be optimally translated to polymer matrices.