Carbon Nanotube (CNTs): Structure, Synthesis, Purification, Functionalisation, Pharmacology, Toxicology, Biodegradation and Application as Nanomedicine and Biosensor

Abstract

It is well acknowledged that carbon nanotubes (CNTs) are a potential new class of nanomaterials for technological advancement. The recent discovery of diverse kinds of carbon nanostructures has sparked interest in the potential applications of these materials in a variety of disciplines. Numerous distinct carbon nanotube (CNT) production methods have been developed, and their characterisation, separation, and manipulation of individual CNTs are now possible. Structure, surface area, surface charge, size distribution, surface chemistry, aggregation state, and purity of the samples all have a significant impact on the reactivity of carbon nanotubes, as does the purity of the samples. Currently, carbon nanotubes (CNTs) are being successfully used in the medicinal, pharmaceutical, and biomedical fields because of their large surface area, which makes them capable of adsorbing or conjugating with a wide range of therapeutic and diagnostic substances (drugs, genes, vaccines, antibodies, biosensors, etc.). They were the first to demonstrate that they are a great vehicle for drug delivery straight into cells without the need for metabolic processing by the body. This paper discusses the different types, structures, and properties of CNTs, as well as CNT synthesis and purification methods, how to functionalize CNTs, and their application in medicinal, pharmaceutical, and biomedical fields, toxicological properties and their assessment, as well as in-vivo pharmacology and biodegradation pathways.

Oxygenated Hydrocarbons from Catalytic Hydrogenation of Carbon Dioxide

“…Table 2 describes the numerous purification steps and the mass variations during each purification stage. Based on this, each step in the purification table is clearly intended to remove some contaminants in order to produce pure CNTs [198]. The definition of "yield" varies considerably from author to author; some claim that yield is based on removing only metallic particles, while others claim that it is based on removing everything extraneous other than the CNTs.…”

Recent Modifications of Carbon Nanotubes for Biomedical Applications

“…Since the discovery of CNTs by Iijima in 1991, [96] the applications of CNTs in the field of nanotechnology have expanded into the field of nanomedicine such as for the use as drug delivery to targeted tissues [97,98]. Compared to other carbonbased nanocarriers like graphene, graphene oxides, fullerenes and etc [99], CNTs have gained wide attention due to their fascinating characteristics such as high surface-to-volume ratio, excellent conductivity and high mechanical strength, and intracellular bioavailability [16,57] (Table 3).…”

Optimizing MWCNT-Based Nanofluids for Photovoltaic/Thermal Cooling through Preparation Parameters

“…Carbon nanotubes have also been used for nanofluids, as they have unique thermal properties and superior thermal capabilities. − These nanotubes come in two types, single-walled and multiwalled, and can have diameters ranging from one nanometer to several nanometers with a cylinder length of several micrometers . Their thermal conductivity (2000–6000 W/m 2 K) is much higher than that of the metallic or metal oxide nanoparticles. − Nanofluids made up of carbon nanotubes can disperse and raise the thermal conductivity of the base fluid . There has been much research done on nanofluids and CNT nanofluids to improve their effectiveness in industrial and civil applications, such as improved bubble adsorption in heat-driven absorption systems, enhanced heat transfers in heat exchangers and solar thermal collectors, and reducing the Leidenfrost effect in cooling processes. − …”