Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5932_Библиотеки_им_академика_М_И_Перельмана

the driving forces behind this adsorption. However, thehydrophobic forces are con­sidered as theprimary mechanismfor the loading of such therapeutics into or onto the surface of CNTs seeing as many anticancer drugs are hydrophobic by nature or include hydrophobic moieties. Additionally, throughelectrostatic interaction, the existence of surface charge on the nanotube surface as a result of chemical pro­cessing can facilitate the adhesion of the ionized molecules [73]. Depending on the π-πstacking in between the CNT surface and aromatic bases/amino acids in the structural backbone of these functional biomolecules, aromatic compounds or mol­ecules containing aromatic groups can be commenced to disassemble and solubi­lize CNTs. Non-covalent functionalization of CNTs is especially appealing since it allows for the attachment of moleculehandles without altering the tubes’ electronic network.

Non-covalent functionalization approaches aresignicant as they do not strongly damage or affect the conguration of CNTs [76]. This is an alternate method of adjusting the interfacial properties of CNTs. Nanotubes can maintain their aromatic structure and, consequently, their inherentelectronic characteristics because of the non-covalent dispersion in the solution. Typical examples of this kind of function­alization often entail the employment of a surfactant, particularly with non-covalent interactions of protein, SWCNTs, and CNT wrapping by taking advantage of the hydrophobic or alternatively π-πstackingby most of the CNTs surface [77]. Numer­ous compounds, including pyrene,polyaniline, poly acrylic acid, siRNA, proteins, DNA, and other biomolecules, have effectively been immobilized across the surface of CNTs via a physical method that incorporates π-πstacking interactions [78]. Addi­tionally, multiple anionic or cationic and non-ionicsurfactants have been employed in the dispersion of CNTs. In the case of drug delivery molecular carriers, polymers are frequently utilized. Despite having a similar dispersion efciency to surfactants, they are an excellent alternative for solubilizing CNT [79].

Phospholipids, a crucial component of plasma membranes, have generally been biologically compatible and might thus be used effectively in biomedical applications. They are employed as a functionalizing group due to their continued amphiphilia. Non-covalent functionalization canlink a hydrophobic portion of the phospholipid to the surface of CNTs, while the polar phosphate group can alternatively be aligned to branched or linear PEG polymers. This method has led to the development of CNT compounds that may be utilized for a variety of biomedical applications, such as bioimaging, biosensing, and targeted DDS, as the CNT based on PEG complexesare muchmore robust and biocompatible in the biological system [5,85].

The oncological application of CNT is primarily divided into their utilization in can­cer diagnosis and treatment. CNTs, with their unique optoelectronic characteristics, have been widely used for cancer detection. Also, other physicochemical properties of CNTs provided novel avenues in the targeted DDS for cancer therapeutics.

5.6.1.2 Carbon nanotubes for cancer therapy

showed a signicant proportion of drug release rate. The nanoparticles were demon­strated to be substantially cytotoxicto HepG2 cells while very mildly cytotoxicto HEK293 cells [94]. Yu etal. (2016)developed a novel SWCNTs-basedDDSfor the sustained delivery of Paclitaxel (PTX). To increase thebiocompatibility of SWCNTs, chitosanwas non-covalently coupled to the walls ofSWCNTs. Additionally, biode­gradable hyaluronan was incorporated into the outermost layer of chitosanto accom­plish the cell-targetingcharacteristic. The ndings demonstrated that PTX release was pH-dependent and improved at lower pH levels (pH 5.5). Intracellular reactive oxygen species (ROS) were signicantly reduced in the modied SWCNTs, which might have increased the activation of mitogen-activated protein kinases and sub­stantially encouraged cellular damage. According to the ndings of western blotting, A549 cells had a high level of expression of apoptosis-related proteins. Cell viability tests and a lactate dehydrogenase (LDH) release experiment showed that PTX-loaded SWCNTs might damage cell membrane structure, which reduced the viability of the A549 cells [95].

had completely eliminated tumors, and their median survival had increased signi­cantly. Especially compared to the untreated tumor, a combination treatment-treated tumor suffered cell disintegration and had a much lower number of proliferating cells, according to histological and immunohistochemistry analyses of tumor tissues. This nding is corroborated by a rise in Hsp70 expression in hyperthermia-treated tumors. In mice undergoing the combination therapy, ow cytometry assessment of the owing lymph nodes revealed an upsurge in dendritic cell penetration and growth [98].

The distinct surface characteristics of CNTs with numerous physicochemical char­acteristics enable their application in several therapeutics for other diseases, such as neurodegenerative diseases and tissue engineering. Adiverse group of sporadic or genetic diseases known as neurodegenerative disorders is all characterized by a grad­ual nervous system failure that results in the degradation of certain central nervous system(CNS) neurons. Parkinson’s disease (PD) andAlzheimer’s disease (AD) are the most prevalent neurodegenerative diseases [99]. The blood-brain barrier (BBB), which makes it challenging to transfer drugs to the brain, is one reason why there are currently few effective therapies for PD. Guo etal. (2017) haveinvestigatedthe viability and therapeutic potential of functional SWCNT-PEGs-Lf,which can ef­cientlytransport and release dopamine (DA) to the brain of PD mice. SWCNTs have strong drug-loading and pH-responsive drug-releasecapabilities and can permeate the cell membrane with remarkable efciency. Polyethylene glycol (PEG)-coated SWCNTs have the potential to expand the concentration gradient of SWCNTs reach­ing the brain by extending thecirculation time. In their study, aside from an evident lactoferrin-nanoparticle (Lf-NP) buildup in the striatum, which has been identied as the pharmaceutical target location of PD, a dual functionalizationof PEG and Lf onto SWCNTs was used, resulting in a particular SWCNT-PEGs-Lfto transport DA. According to the outcomes of in-vitro experiments, the activity of PC12 cells greatly riseswhen 20 mol L are deposited onto SWCNT-PEG, and the concentrations of lactate dehydrogenase (LDH) along with ROSsignicantly decrease [100]. Although the carbon nanotubes, including the SWCNTs and MWCNTs, have been extensively employed for diagnos­ing PD through electrochemical sensors [97], the literature related to their applica­tion in PD treatment is scant.

including behavioral abnormaliti es, cognitive decits, disruption toeveryday activ­ities, and so forth. Medications like donepezil,galantamine, berberine (BRB),and rivastigmine that enhance the concentrations of acetylcholine in the brain tissue are used in the commonly accepted therapy methods for AD patients. It has been shown that transporting neuro-pharmaceutical drugs to the interior microenvironment of brain microglial cells is more successful when done with MWCNTs. MWCNTs have various benets over SWCNTs, including easier large-scale manufacturing, cheaper production cost, and enhanced chemical stability and drug adsorption potential. To effectively alleviate Alzheimer’s disease [101], Lohan et al. (2017) described the comprehensive production of berberine (BRB)-loadedMWCNTswithphospholipid and polysorbatecoating (Figure5.3). Acentral composite design (FCCD) was used for comprehensive optimization using the design of experiments (DoE), and the opti­mum formulation was selected using the statistical desirability function. The opti­mized formulation had a size of the particles of 186 nm with68.6% drug loading and a drug release rate of 96% in 16hours.Confocal tests conrmed the BRB-loaded MWCNT formulations’ propensity to be taken up by SH-SY5Y cell lines. When compared to a pure drug, in-vivo pharmacokinetic experiments on rats revealed a considerable improvement in the pace and amount of druguptake in the plasma and brain tissues. The improved performance effectiveness of the synthesized MWCNT compounds was conrmed by behavioral testing using the Morris maze test. Inter­estingly, the memory subsystem of the phospholipid-coated and polysorbate-coated MWCNTs signicantly improved from the 18th to the 20th day compared to other groups [102].

Similarly, the intercalated discs (IDs) linking the cardiomyocytes are not suf­ciently remodeled by existing cardiac tissue engineering techniques. CNTs could help to get around this restriction. ACNT/collagen patch was designed by Sun etal. (2015) to improve intercalated disc formation in cardiac myocytes. A variety of cellular signaling pathways, notably focal adhesion kinase (FAK), integrin-linked kinase (ILK), and Src, are activated in the myocardial by the mechano-transducer