Development and evaluation of targeting ligand-anchored CNTs as prospective targeted drug delivery system

Ligand-conjugated multiwalled carbon nanotubes for cancer targeted drug delivery

Multiwalled carbon nanotubes (MWCNTs) are at the forefront of nanotechnology-based advancements in cancer therapy, particularly in the field of targeted drug delivery. The nanotubes are characterized by their concentric graphene layers, which give them outstanding structural strength. They can deliver substantial doses of therapeutic agents, potentially reducing treatment frequency and improving patient compliance. MWCNTs' diminutive size and modifiable surface enable them to have a high drug loading capacity and penetrate biological barriers. As a result of the extensive research on these nanomaterials, they have been studied extensively as synthetic and chemically functionalized molecules, which can be combined with various ligands (such as folic acid, antibodies, peptides, mannose, galactose, polymers) and linkers, and to deliver anticancer drugs, including but not limited to paclitaxel, docetaxel, cisplatin, doxorubicin, tamoxifen, methotrexate, quercetin and others, to cancer cells. This functionalization facilitates selective targeting of cancer cells, as these ligands bind to specific receptors overexpressed in tumor cells. By sparing non-cancerous cells and delivering the therapeutic payload precisely to cancer cells, this therapeutic payload delivery ability reduces chemotherapy systemic toxicity. There is great potential for MWCNTs to be used as targeted delivery systems for drugs. In this review, we discuss techniques for functionalizing and conjugating MWCNTs to drugs using natural and biomacromolecular linkers, which can bind to the cancer cells' receptors/biomolecules. Using MWCNTs to administer cancer drugs is a transformative approach to cancer treatment that combines nanotechnology and pharmacotherapy. It is an exciting and rich field of research to explore and optimize MWCNTs for drug delivery purposes, which could result in significant benefits for cancer patients.

Carbon Nanomaterials (CNMs) in Cancer Therapy: A Database of CNM-Based Nanocarrier Systems

Carbon nanomaterials (CNMs) are an incredibly versatile class of materials that can be used as scaffolds to construct anticancer nanocarrier systems. The ease of chemical functionalisation, biocompatibility, and intrinsic therapeutic capabilities of many of these nanoparticles can be leveraged to design effective anticancer systems. This article is the first comprehensive review of CNM-based nanocarrier systems that incorporate approved chemotherapy drugs, and many different types of CNMs and chemotherapy agents are discussed. Almost 200 examples of these nanocarrier systems have been analysed and compiled into a database. The entries are organised by anticancer drug type, and the composition, drug loading/release metrics, and experimental results from these systems have been compiled. Our analysis reveals graphene, and particularly graphene oxide (GO), as the most frequently employed CNM, with carbon nanotubes and carbon dots following in popularity. Moreover, the database encompasses various chemotherapeutic agents, with antimicrotubule agents being the most common payload due to their compatibility with CNM surfaces. The benefits of the identified systems are discussed, and the factors affecting their efficacy are detailed.

Microwave-Assisted Functionalization of Multi-Walled Carbon Nanotubes for Biosensor and Drug Delivery Applications

Microwave-assisted synthetic methods have emerged as a popular technique for surface modification and the functionalization of multi-walled carbon nanotubes (MWCNTs) for diverse drug delivery applications. Microwave-induced functionalization of MWCNTs provides a high functionalization and requires less time than conventional techniques. Microwave methods are simple, fast, and effective for the covalent and noncovalent conjugation of MWCNTs with various biomolecules and polymers. The present review focuses on the synthetic and drug delivery applications of microwave irradiation techniques (MITs) for the functionalization of MWCNTs, using amino acids and other molecular frameworks containing amino groups, vitamins, proteins, epoxy moieties, metal nanoparticles, and polymers.

In vitro targeting and selective killing of mcf-7 and colo320dm cells by 5-fluorouracil anchored to carboxylated SWCNTs and MWCNTs

The intention of the present work was to synthesize the f-MWCNT and f-SWCNT terminated with proper functional group, loading of 5-Flurouracil and to perform cytotoxic activity. Functionalization of MWCNTs and SWCNTs was achieved through the acid treatment (H₂SO₄ + HNO₃). 5-flurouracil was loaded into the prepared functionalized CNTs, thereafter; in vitro drug loading capacity and % drug release were calculated. Also the prepared f-CNTs, 5-flurouracil loaded CNTs were distinguished by using SEM, TGA, DSC, X-ray diffraction, Raman and FTIR spectroscopy. MCF-7 and COLO320DM cells were treated with selected concentrations of 5-FU loaded f-MWCNTs and f-SWCNTs to estimate the cytotoxic activity. It was observed that 5-FU loaded f-SWCNTs showed good activity against selected cell lines than others. Moreover, apoptosis percentage was reported to be 84.46 ± 4.3515 and 92.78 ± 2.6549 for 5-FU loaded f-SWCNTs against MCF-7 and COLO320DM cells respectively. It is evident from the results that the prepared drug loaded CNTs have comparable antitumor activity in cancer cell lines.

Exploring pH dependent delivery of 5-fluorouracil from functionalized multi-walled carbon nanotubes

Multi-walled carbon nanotubes (MWCNTs) can be applied for pH-sensitive delivery of anticancer drugs. Due to the importance of 5-fluorouracil (5-FU) in different tumor therapy regimens, it has been widely used in different pH dependent drug delivery systems. To investigate the pH effects on loading (and release) of 5-FU on (and from) the functionalized MWCNTs and propose the optimum condition for drug delivery, both macroscopic and microscopic studies were carried out using chromatography and molecular dynamic simulation at different conditions. For both levels of studies, different analytical approaches were performed to assess the validity of the methods. The experimental results revealed that 5-FU has more binding affinity to the surface of the nanocarrier at physiological pH (pH = 7.4) and showed more release at acidic conditions (pH = 5.0). Meanwhile it has been observed that basic pH (pH = 9.0) can lead to a dramatic decrease effect on loading of the drug. The results of this study can be used to suggest the optimum pH levels for nanocarbon based formulations of 5-FU in cancer therapy.

Drug Delivery With Carbon-Based Nanomaterials as Versatile Nanocarriers: Progress and Prospects

With growing interest, a large number of researches have been conducted on carbon-based nanomaterials (CBNs). However, their uses are limited due to comprehensive potential environmental and human health effects. It is often confusing for researchers to make an informed choice regarding the versatile carbon-based nanocarrier system and its potential applications. This review has highlighted emerging applications and cutting-edge progress of CBNs in drug delivery. Some critical factors like enzymatic degradation, surface modification, biological interactions, and bio-corona have been discussed here. These factors will help to fabricate CBNs for effective drug delivery. This review also addresses recent advancements in carbon-based target specific and release controlled drug delivery to improve disease treatment. The scientific community has turned their research efforts into the development of novel production methods of CBNs to make their production more attractive to the industrial sector. Due to the nanosize and diversified physical properties, these CBNs have demonstrated distinct biological interaction. Thus long-term preclinical toxicity study is recommended before finally translating to clinical application.

Folate-Functionalized Mesoporous Hollow SnO2 Nanofibers as a Targeting Drug Carrier to Improve the Antitumor Effect of Paclitaxel for Liver Cancer Therapy

In this study, we prepared PTX-loaded mesoporous hollow SnO₂ nanofibers conjugated with folic acid (SFNFP) for liver cancer therapy. According to SEM and TEM characterization, SFNF showed a mesoporous hollow structure. The average outer diameter was 200 nm, and the wall thickness was 50 nm. The DSC and XRD study showed that PTX in the channels of nanofibers was present in an amorphous state. The in vitro release experiments demonstrated that SFNF could efficiently improve the dissolution rate of PTX. Both in vitro cell experiments and in vivo antitumor experiments showed that SFNFP could efficiently inhibit the growth of liver cancer cells. Therefore, SFNF is a promising targeting antitumor drug delivery carrier.

Chemotherapeutic drug targeting to lungs by way of microspheres after intravenous administration

Purpose

Currently, microsphere technology plays a major role in the development of many new cancer therapies. In the current study, we proposed a targeted drug-delivery system to improve the treatment efficacy of one of the common conventional chemotherapeutic drugs used to treat lung tumors, 5-fluorouracil (5-FU).

Materials and methods

Following the preparation and optimization of small, solid micro-spheres, ranging in diameter between 5 and 15 µm, the final product 5-fluorouracil gelatin (5-FUG) was formulated using a Buchi Nano Spray Dryer by varying the drug:polymer ratio.

Results

Particle yield was calculated as 65% ± 1.2%, and the drug content in the formulation was recorded as 74% ± 1.6%. Particle surface morphology was examined as shriveled shape (crumpled/folded); particle size distribution displayed a binomial distribution, with a mean diameter of 9.6 µm. In vitro drug release studies revealed that ~36.4% of the 5-FU in 5-FUG was released in the first hour after injection. Clinically, this would lead to initial or burst release, facilitating a quick rise to therapeutic levels. In contrast to the pure 5-FU drug (89.2% of the drug released in the first 30 minutes), 99.1% of the drug in 5-FUG was released from the spray-dried particles for a period of 12 hours. A two-compartment model was used to generate plasma concentration–time curves. 5-FUG injection has a much different distribution in vivo in contrast to intravenous injection of 5-FU. In addition, the half-life after intravenous injection of 5-FUG, t_1/2(α) = 1.23 hours and t_1/2(β) = 18.3 hours, was considerably longer than that of 5-FU, t_1/2(α) = 0.34 hours and t_1/2(β) = 8.62 hours. Examination of stained lung tissue sections showed no histopathological tissue changes or evidence of gross pathology. In addition, the optimized formulation demonstrated an increased stability under both long-term and refrigerated storage conditions.

Conclusion

Our goal was to develop similar delivery systems for other chemotherapeutic drugs that are site specific to different disease models/tumor types.

Nanocarrier for levodopa Parkinson therapeutic drug; comprehensive benserazide analysis

Loss of dopamine-secreting neurons in the midbrain causes Parkinson's disease. L-DOPA, the precursor to the neurotransmitters dopamine, crosses vast majority of physiological and biochemical barriers that dopamine cannot. But most levodopa is decarboxylated to dopamine before it reaches the brain. This causes to little therapeutic gain with strong peripheral side effects. Benserazide is an irreversible inhibitor of peripheral aromatic L-amino acid decarboxylase that prevents the breakdown of levodopa in the bloodstream. The challenges are to increase the therapeutic efficiency, the bioavailability and decreasing the unfavourable side effects of Levodopa drug. Biocompatible nano-sized drug carriers could address these challenges at molecular level. Thus calculations of drug loading ability of acid-functionalized CNT for the benserazide as a nanodug carrier complex for L-DOPA were performed. In this regard, evaluation of all adsorption features of the most stable conformer of benserazide molecule onto carboxylated carbon nanotube is critical. To determine the minimum energy conformer of benserazide, the molecular structure and conformational analysis of 512 possible conformers have been subjected to first principle quantum mechanical calculations. Our work established a novel and easy-to-make formulation of benserazide/carboxylated CNT conjugate with extremely high drug loading efficiency of Levodopa for Parkinson disease treatment.

Nanocarrier based approaches for targeting breast cancer stem cells

Breast cancer stem cells (BCSCs) are heterogeneous subpopulation of tumour initiating cells within breast tumours. They are spared even after chemotherapy and responsible for tumour relapse. Targeting BCSCs is, therefore, necessary to achieve radical cure in breast cancer. Despite the availability of agents targeting BCSCs, their clinical application is limited due to their off-target effects and bioavailability issues. Nanotechnology based drug carriers (nanocarriers) offer various advantages to deliver anti-BCSCs agents specifically to their target sites by overcoming their bioavailability issues. In this review, we describe various strategies for targeting BCSCs using nanocarriers.

Polyarginine and PEG-AEYLR comodified nanostructured lipid carrier: 10mol% uncleavable PEG-AEYLR showed no shielding effect to polyarginine in vitro while maintaining good tumor targeting in vivo

We constructed a dual ligands-modified nanostructured lipid carrier (NLC) called PAR-NLC, in which the epidermal growth factor receptor (EGFR)-targeted small peptide AEYLR was attached to the distal end of PEG₂₀₀₀ anchored on the NLC surface naming PEG-AEYLR, and poly-arginine (R8) as a classic cell-penetrating peptide was attached directly to the NLC surface. PAR-NLC was near-spherical particle with average size ∼50 nm and zeta potential at +14.09 mV; the cellular uptake of PAR-NLC showed synergistic effect of the two peptides, presented as significant superior cellular uptake in EGFR-positive cells NCI-H1299 and S180 over EGFR-negative cell K562. In the animal optical imaging study, 2 h after the administration of the Dir-loaded PAR-NLC, maximum Dir signal appeared in tumor tissue, indicating prompt tumor targeting effect, as time prolonged to 48 h, the Dir signal attenuated in the organs except tumor, suggesting constant clearance from the body. In the in vivo antitumor study, in premise of the same dose, paclitaxel-loaded PAR-NLC exhibited better antitumor and safety effect than Taxol, the body weight of the mice was more stable and tumor size was smaller. In summary, PAR-NLC was a potential drug carrier to deliver anticancer drugs safely and effectively.