In this paper, bromination methods of three morphological forms of carbon nanotubes (CNT): single-walled, double-walled and multi-walled, are reviewed along with their characteristics and purification protocols using liquid bromine. Different functionalization methods of the CNT with bromine in the liquid, gas and plasma phases, using electrochemical and electrothermal method, under microwave conditions in the presence of Lewis acids or radical precursors are also discussed.

Cyclodextrin-based nanosponges (CD-NS) are a novel class of polymers cross-linked with a three-dimensional network and can be obtained from cyclodextrins (CD) and pyromellitic dianhydride. Their properties, such as their ability to form an inclusion complex with drugs, can be used in biomedical science, as nanosponges influence stability, toxicity, selectivity, and controlled release. Most pharmaceutical research use CD-NS for the delivery of drugs in cancer treatment. Application of molecular targeting techniques result in increased selectivity of CD-NS; for example, the addition of disulfide bridges to the polymer structure makes the nanosponge sensitive to the presence of glutathione, as it can reduce such disulfide bonds to thiol moieties. Other delivery applications include dermal transport of pain killers or photosensitizers and delivery of oxygen to heart cells. This gives rise to the opportunity to transition to medical scaffolds, but more, in modern times, to create an ultrasensitive biosensor, which employs the techniques of surface-modified nanoparticles and molecularly imprinted polymers (MIP). The following review focuses on the biomedical research of cyclodextrin polymers cross-linked via dianhydrides of carboxylic acids.

Water treated with low-temperature, low-pressure glow plasma (GP) in contact with air stimulates various microorganisms, the growth of various plants and provides healthy breeding of various animals. In this paper, we present water treated with GP under oxygen-free nitrogen. It is potentially suitable for breeding anaerobic microorganisms, and increasing the crops of plants utilizing atmospheric nitrogen. Deionized water saturated with oxygen-free nitrogen was treated for 5 to 90 min with low-temperature glow plasma (GP). That operation produced nitrogen in various exited states depending on the treatment time. These excited nitrogen molecules built aqueous clathrates around them. The number and structure of those clathrates depended on the time of the treatment with GP. In terms of mass, density, pH, conductivity, surface tension, Ultraviolet-Visible (UV-VIS), Fourier Transformation Infrared (FTIR), Raman and Electron Spin Resonance (ESR) spectra as well as Differential Scanning Calorimetry (DSC), the macrostructure of water saturated with nitrogen treated with GP strongly depended on the treatment time. Based on the entropy criterion, the macrostructure formed on 30 and 5 min treatment was the most and least organized, respectively.

The bromination of multi-walled carbon nanotubes (MWCNT) was performed with vapor bromine in a closed vessel, and they were subjected to intensive stirring with a magnetic stirrer for up to 14 days. The efficiency of bromination was compared depending upon duration. The structure and surface of the crude and purified products were characterized by detailed physicochemical analyses, such as SEM/EDS, TEM, XRD, TGA, Raman, and XPS spectroscopies. The studies confirmed the presence of bromine covalently bound with nanotubes as well as the formation of inclusion MWCNT–Br₂ complexes. It was confirmed that Br₂ molecules are absorbed on the surface of nanotubes (forming the CNT-Br₂ complex), while they can dissociate close to dangling bonds at CNT defect sites with the formation of covalent C−Br bonds. Thus, any covalent attachment of bromine to the graphitic surface achieved around room temperature is likely related to the defects in the MWCNTs. The best results, i.e., the highest amount of attached Br₂, were obtained for brominated nanotubes brominated for 10 days, with the content of covalently bound bromine being 0.68 at% (by XPS).