Fullerenol-Based Intracellular Delivery of Methotrexate: A Water-Soluble Nanoconjugate for Enhanced Cytotoxicity and Improved Pharmacokinetics

Disturbing cytoskeleton by engineered nanomaterials for enhanced cancer therapeutics

Cytoskeleton plays a significant role in the shape change, migration, movement, adhesion, cytokinesis, and phagocytosis of tumor cells. In clinical practice, some anti-cancer drugs achieve cytoskeletal therapeutic effects by acting on different cytoskeletal protein components. However, in the absence of cell-specific targeting, unnecessary cytoskeletal recombination in organisms would be disastrous, which would also bring about severe side effects during anticancer process. Nanomedicine have been proven to be superior to some small molecule drugs in cancer treatment due to better stability and targeting, and lower side effects. Therefore, this review summarized the recent developments of various nanomaterials disturbing cytoskeleton for enhanced cancer therapeutics, including carbon, noble metals, metal oxides, black phosphorus, calcium, silicon, polymers, peptides, and metal-organic frameworks, etc. A comprehensive analysis of the characteristics of cytoskeleton therapy as well as the future prospects and challenges towards clinical application were also discussed. We aim to drive on this emerging topic through refreshing perspectives based on our own work and what we have also learnt from others. This review will help researchers quickly understand relevant cytoskeletal therapeutic information to further advance the development of cancer nanomedicine.

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.

Potential Medical Use of Fullerenols After Two Decades of Oncology Research

Fullerenes are carbon molecules that are found in nature in various forms. They are composed of hexagonal and pentagonal rings that create closed structures. Almost 4 decades ago, fullerenes were identified in the form of C60 and C70, and following the award of the Nobel Prize in Chemistry for this discovery in 1996, many laboratories started working on their water-soluble derivatives that could be used in different industries, including pharmaceutical industries. One of the first fullerene forms that was the focus of different research groups was fullerenol, C60(OH)n (n  =  2-44). Both in-vitro and in-vivo studies have shown that polyhydroxylate fullerene derivatives can potentially be used as either antioxidative agents or cytostatics (depending on their co-administration, forms, and concentration/dose) in biological systems. The current review aimed to present a critical view of the potential applications and limitations of fullerenols in oncology, as understood from the past 2 decades of research.

Novel C60 Fullerenol-Gentamicin Conjugate–Physicochemical Characterization and Evaluation of Antibacterial and Cytotoxic Properties

This study aimed to develop, characterize, and evaluate antibacterial and cytotoxic properties of novel fullerene derivative composed of C₆₀ fullerenol and standard aminoglycoside antibiotic–gentamicin (C₆₀ fullerenol-gentamicin conjugate). The successful introduction of gentamicin to fullerenol was confirmed by X-ray photoelectron spectroscopy which together with thermogravimetric and spectroscopic analysis revealing the formula of the composition as C₆₀(OH)₁₂(GLYMO)₁₁(Gentamicin)_0.8. The dynamic light scattering (DLS) revealed that conjugate possessed ability to form agglomerates in water (size around 115 nm), while Zeta potential measurements demonstrated that such agglomerates possessed neutral character. In vitro biological assays indicated that obtained C₆₀ fullerenol-gentamicin conjugate possessed the same antibacterial activity as standard gentamicin against Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli, which proves that combination of fullerenol with gentamicin does not cause the loss of antibacterial activity of antibiotic. Moreover, cytotoxicity assessment demonstrated that obtained fullerenol-gentamicin derivative did not decrease viability of normal human fibroblasts (model eukaryotic cells) compared to control fibroblasts. Thus, taking into account all of the results, it can be stated that this research presents effective method to fabricate C₆₀ fullerenol-gentamicin conjugate and proves that such derivative possesses desired antibacterial properties without unfavorable cytotoxic effects towards eukaryotic cells in vitro. These promising preliminary results indicate that obtained C₆₀ fullerenol-gentamicin conjugate could have biomedical potential. It may be presumed that obtained fullerenol may be used as an effective carrier for antibiotic, and developed fullerenol-gentamicin conjugate may be apply locally (i.e., at the wound site). Moreover, in future we will evaluate possibility of its applications in inter alia tissue engineering, namely as a component of wound dressings and implantable biomaterials.

Use of graphene-based materials as carriers of bioactive agents

Graphene possesses a large specific surface area, a high Young's modulus, high fracture strength, high electrical conductivity, and excellent optical performance. It has been widely studied for biomedical use since its first appearance in the literature. This article offers an overview of the latest advances in the design of graphene-based materials for delivery of bioactive agents. To enhance the translation of these carriers into practical use, the toxicity involved is needed to be examined in future research in more detail. In addition, guidelines for standardizing experimental conditions during the evaluation of the performance of graphene-based materials are required to be established so that candidates showing higher practical potential can be more effectively identified for further development. This can streamline the optimization and use of graphene-based materials in delivery applications.

Assessing the viability of carbamoylethyl pullulan-g-stearic acid based smart polymeric micelles for tumor targeting of raloxifene

The present investigation entails the synthesis of smart pullulan polymeric micelles for evaluating its tumor targeting potential. For this purpose, two step polymerization synthesis reactions were conducted. In the first step, carbamoylethylation occurs by reaction of the free alcoholic moieties at 6th position of glucopyranose unit of pullulan with acrylamide in presence of alkali to obtain carbamoylethyl pullulan (CmP). In the second step, CmP undergoes graft polymerization with stearic acid (SA) to obtain CmP-g-stearic acid diblock co-polymer (CmP-g-SA) as evident from FTIR and NMR analysis. The XpRD spectra showed crystalline nature that was further confirmed by SEM indicating rough and poly-porous morphology. The QbD based optimized formulations of raloxifene HCl (RLX) loaded polymeric micelles (RLX PMs) exhibited pH-dependent release profile with added advantage of 1.2 times reduction in percentage hemolysis giving substantial compatibility with erythrocytes. In vivo pharmacokinetic performance of RLX PMs suggested enhanced mean residence time and volume of distribution. Besides, the biodistribution study of RLX PMs manifested enhanced entry of RLX in mammary carcinoma tissues as compared to normal tissues suggested that CmP-g-SA based micelles enhanced the anti-tumor activity of RLX. Overall, the findings pointed toward the biocompatibility of CmP-g-SA as a potential carrier system for the delivery of RLX.

Exploring the feasibility of carbamoylethyl pullulan-g-palmitic acid polymeric micelles for the effective targeting of raloxifene to breast tumor: Optimization and preclinical evaluation

Carbamoylethyl pullulan-grafted palmitic acid (CP-g-PA), a novel self-assembled polymer was synthesized and examined for its efficacy in delivering the raloxifene (RA) to mammary carcinoma. The synthesized CP-g-PA was confirmed by evaluating through various spectral and morphological attributes. Further, the central composite design-response surface methodology with two factors at three levels was utilized to obtain the optimized and stable polymeric micelles. The optimized formulation was subjected to in vitro and in vivo evaluation. RA loaded polymeric micelles (RA-PMs) were spherical in shape with particle size less than 100 nm and high entrapment efficiency (77.02%). The developed formulation exhibited pH-dependent release profile of RA when loaded in polymeric micelles and provides substantial compatibility to erythrocytes. In vivo pharmacokinetic study demonstrates that RA-PMs offers higher mean residence time and volume of distribution as compared to pure RA. Besides, the biodistribution study manifested enhanced drug concentration in tumor and decreased concentration in other tissue as compared to pure drug. The treatment with RA-PMs also increases the median survival time, tumor inhibition rate and % increase in life span of the tumor bearing rats. Overall, the results pointed towards the overwhelming response of RA when loaded into micelles made from CP-g-PA.

Conventional Nanosized Drug Delivery Systems for Cancer Applications

Clinical responses and tolerability of conventional nanocarriers (NCs) are sometimes different from those expected in anticancer therapy. Thus, new smart drug delivery systems (DDSs) with stimuli-responsive properties and novel materials have been developed. Several clinical trials demonstrated that these DDSs have better clinical therapeutic efficacy in the treatment of many cancers than free drugs. Composition of DDSs and their surface properties increase the specific targeting of therapeutics versus cancer cells, without affecting healthy tissues, and thus limiting their toxicity versus unspecific tissues. Herein, an extensive revision of literature on NCs used as DDSs for cancer applications has been performed using the available bibliographic databases.

Preparation, preliminary pharmacokinetics and brain tissue distribution of Tanshinone IIA and Tetramethylpyrazine composite nanoemulsions

Objective: Tanshinone IIA (TSN) and Tetramethylpyrazine (TMP) were combined in a composite, oil-in-water nanoemulsions (TSN/TMP O/W NEs) was prepared to prolong in vitro and vivo circulation time, and enhance the bioavailability of TSN. Material and methods: Physicochemical characterization of TSN/TMP O/W NEs was characterized systematically. The in vitro dissolution and in vivo pharmacokinetic experiments of TSN/TMP O/W NEs were also evaluated. Result: A formulation was optimized, yielding a 32.5 nm average particle size, an encapsulation efficiency of over 95 %, and were spherical in shape as shown by TEM. TSN/TMP O/W NEs were shown to extend the release and availability in vitro compared to raw compounds. In pharmacokinetic study, the AUC_0→∞ and t_1/2 of the TSN/TMP O/W NEs were 481.50 mg/L*min and 346.39 min higher than TSN solution, respectively. Brain tissue concentration of TSN was enhanced with TSN/TMP O/W NEs over raw TSN and even TSN O/W NEs. Conclusions: Therefore, nanoemulsions are an effective carrier to increase encapsulation efficiency of drugs, improve bioavailability and brain penetration for TSN - which is further enhanced by pairing with the co-delivery of TMP, providing a promising drug delivery.

Structure Simulation of Cisplatin Complexes with Single-Walled Carbon Nanotubes and Fullerenol

Structure and energy calculations of modified complexes of single-walled carbon nanotubes and fullerenol C[Formula: see text](OH)[Formula: see text] with cisplatin have been performed using the quantum chemical method at the DFT/B3LYP/SV/Lanl2DZ level. The nanotubes were modified with COOH groups at the end and sidewall of the nanotube and cisplatin molecules. The dependence of their structure on the presence of a solvent was established.

Easy, efficient and versatile one-pot synthesis of Janus-type-substituted fullerenols

An efficient one-pot synthesis for Janus-type fullerenol derivatives and how to characterize them is reported. This synthesis provides access to asymmetrically substituted fullerenol with five substituents on one pole of the fullerene and polyhydroxylation moieties, mostly ether and hydroxy groups, on the rest of the fullerene core. As substituents a broad variety of primary amines can be used to obtain Janus-type amphiphilic fullerenols in good to excellent yield. These fullerenol amphiphiles can serve as suitable precursors for further reactions resulting in new applications for fullerenols.

Aspartic acid tagged carbon nanotubols as a tool to deliver docetaxel to breast cancer cells: Reduced hemotoxicity with improved cytotoxicity

The present study aimed to explore the potential of hydroxylated carbon nanotubes (CNTnols) conjugated with aspartic acid for the delivery of docetaxel (DTX) to breast cancer cells. The conjugate was well-characterized by FT-IR, NMR, XRD and FE-SEM. The nanoconjugate offered a hydrodynamic diameter of 86.31 ± 1.02 nm, with a PDI of 0.113 and zeta potential of -41.6 ± 0.17 mV. The designed nanosystem offered a controlled & pH dependent release vouching release of drug in the cancerous cytosol, not in blood, assuring delivery of the pay-load to the site of action. The carriers offered substantial hemocompatibility and lower plasma protein binding, ensuring more drug available at the site of action. The in-vitro cell viability studies in MDA MB-231 cells inferred approx. 2.8 times enhancement in the cytotoxicity potential of the conjugate vis-à-vis plain drug. Pharmacokinetic studies also corroborated the superiority of the designed nanoconjugate in terms of enhanced bioavailable fractions, reduced clearance and longer bioresidence to that of plain docetaxel. The present studies, successfully provide a workable nanomedicine, loaded with a BCS class-IV drug, for improved efficacy and safety in breast cancer.