In vivo drug delivery of gemcitabine with PEGylated single-walled carbon nanotubes

Epigallocatechin-3-gallate Synergistically Inhibits the Proliferation of Lung Cancer Cells with Gemcitabine by Induction of Apoptosis Mediated by ROS Generation

The present study focused on the formulation, characterization, and evaluation of solid lipid nanoparticles (SLNs) loaded with gemcitabine (GEM) and epigallocatechin-3-gallate (EGCG) for lung cancer treatment. A 2-level, 3-factor factorial design was used to optimize various process parameters in the preparation of SLNs. The average particle size and polydispersity index (PDI) of GEM-EGCG SLNs were found to be 122.8 ± 8.02 and 0.1738 ± 0.02, respectively. Drug loading and release studies indicated a sustained release behavior for GEM-EGCG SLNs, with release kinetics confirmed by the Higuchi model. Cell viability and anticancer activities were assessed using the MTT assay, which determined an IC50 value of 12.5 μg/mL for GEM-EGCG SLNs against A549 cell lines (lung carcinoma epithelial cells). The SLNs were able to internalize into the nuclei of cells, likely due to their small particle size, and were effective in killing cancer cells. Additionally, a study of ROS production-mediated apoptosis of A549 cells was performed through FACS. GEM-EGCG SLNs were found to be stable for 3 months. In vivo studies revealed better drug distribution in the lungs and improved pharmacokinetic profile compared with pure drugs. Overall, the results suggest that combining GEM and EGCG in biocompatible SLNs has resulted in synergistic antitumor potential and improved bioavailability for both drugs, making it a promising anticancer therapeutic regimen against lung cancer.

Polymer removal and dispersion exchange of (10,5) chiral carbon nanotubes with enhanced 1.5 μm photoluminescence

Singe-chirality single-walled carbon nanotubes (SWCNTs) produced by selective polymer extraction have been actively investigated for their semiconductor applications. However, to fulfil the needs of biocompatible applications, the organic solvents in polymer-sorted SWCNTs impose a limitation. In this study, we developed a novel strategy for organic-to-aqueous phase exchange, which involves thoroughly removing polymers from the sorted SWCNTs, followed by surfactant covering and redispersing of the cleaned SWCNTs in water. Importantly, the obtained aqueous system allows us to perform sp3 functionalization of the SWCNTs, leading to a strong photoluminescence emission at 1550 nm from the defect sites of (10,5) SWCNTs. These functionalized SWCNTs as infrared light emitters show considerable potential for bioimaging applications. This exchange-and-functionalization strategy opens the door for future biocompatible applications of polymer-sorted SWCNTs.

Development and evaluation of a protease inhibitor antiretroviral drug-loaded carbon nanotube delivery system for enhanced efficacy in HIV treatment

The primary objective of this study was to enhance the effectiveness of the protease inhibitor antiretroviral drug by designing a novel delivery system using carboxylated multiwalled carbon nanotubes (COOH-MWCNTs). To achieve this, Fosamprenavir calcium (FPV), a prodrug of amprenavir known for inhibiting the proteolytic cleavage of immature virions, was selected as the protease inhibitor antiretroviral drug, and loaded onto COOH-MWCNTs using a direct loading method. The structural specificity of the drug-loaded MWCNTs, the percent entrapment efficiency, and in vitro drug release were rigorously evaluated for the developed formulation, referred to as FPV-MWCNT. Fourier transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, and atomic force microscopy (AFM) techniques were employed to confirm the structural integrity and specificity of the FPV-MWCNT formulation. The results demonstrated a remarkable entrapment efficiency of 79.57 ± 0.4 %, indicating the successful loading of FPV onto COOH-MWCNTs. FE-SEM and AFM analyses further confirmed the well-dispersed and elongated structure of the FPV-MWCNT formulation, without any signs of fracture, ensuring the stability and integrity of the drug delivery system. Moreover, particle size analysis revealed an average size of 290.1 nm, firmly establishing the nanoscale range of the formulation, with a zeta potential of 0.230 mV, signifying the system's colloidal stability. In vitro drug release studies conducted in methanolic phosphate buffer saline (PBS) at pH 7.4 and methanolic acetate buffer at pH 5 demonstrated sustained drug release from the FPV-MWCNT formulation. Over a period of 96 h, the formulation exhibited a cumulative drug release of 91.43 ± 2.3 %, showcasing the controlled and sustained release profile. Furthermore, hemolysis studies indicated a notable reduction in the toxicity of both FPV and MWCNT upon conjugation, although the percent hemolysis increased with higher concentrations, suggesting the need for careful consideration of dosage levels. In conclusion, the findings from this study underscore the potential of the FPV-MWCNT formulation as an effective and promising drug-conjugated system for delivering antiretroviral drugs. The successful encapsulation, sustained drug release, and reduced toxicity make FPV-MWCNT a compelling candidate for enhancing the therapeutic efficacy of protease inhibitor antiretroviral drugs in the treatment of HIV. The developed delivery system holds great promise for future advancements in HIV treatment and paves the way for further research and development in the field of drug delivery utilizing carbon nanotube-based systems.

Nano-mediated strategy for targeting and treatment of non-small cell lung cancer (NSCLC)

Lung cancer is the most common type of cancer, with over 2.1 million cases diagnosed annually worldwide. It has a high incidence and mortality rate, leading to extensive research into various treatment options, including the use of nanomaterial-based carriers for drug delivery. With regard to cancer treatment, the distinct biological and physico-chemical features of nano-structures have acquired considerable impetus as drug delivery system (DDS) for delivering medication combinations or combining diagnostics and targeted therapy. This review focuses on the use of nanomedicine-based drug delivery systems in the treatment of lung cancer, including the use of lipid, polymer, and carbon-based nanomaterials for traditional therapies such as chemotherapy, radiotherapy, and phototherapy. The review also discusses the potential of stimuli-responsive nanomaterials for drug delivery in lung cancer, and the limitations and opportunities for improving the design of nano-based materials for the treatment of non-small cell lung cancer (NSCLC).

Research progress on carbon materials in tumor photothermal therapy

At present, cancer remains one of the leading causes of human death worldwide, and surgery, radiotherapy and chemotherapy are still the main methods of cancer treatment. However, these treatments have their drawbacks. Surgical treatment often struggles with the complete removal of tumor tissue, leading to a high risk of cancer recurrence. Additionally, chemotherapy drugs have a significant impact on overall health and can easily result in drug resistance. The high risk and mortality of cancer and other reasons promote scientific researchers to unremittingly develop and find a more accurate and faster diagnosis strategy and effective cancer treatment method. Photothermal therapy, which utilizes near-infrared light, offers deeper tissue penetration and minimal damage to surrounding healthy tissues. Compared to conventional radiotherapy and other treatment methods, photothermal therapy boasts several advantages, including high efficiency, non-invasiveness, simplicity, minimal toxicity, and fewer side effects. Photothermal nanomaterials can be categorized as either organic or inorganic materials. This review primarily focuses on the behavior of carbon materials as inorganic materials and their role in tumor photothermal treatment. Furthermore, the challenges faced by carbon materials in photothermal treatment are discussed.

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.

Recent advances in modification of novel carbon-based composites: Synthesis, properties, and biotechnological/ biomedical applications

Nowadays, carbon-based materials owing to great interest in biomedical science/biotechnology and applied for effective diagnosis and treatment of disease. To enhance the effectiveness of carbon nanotubes (CNTs)/graphene-based materials for bio-medical science/technology applications, different kinds of surface modification/functionalization were developed for the attachment of metal oxides nanostructures, biomolecules and polymers. The attachment of pharmaceutical agents with CNTs/graphene, make it a favorable candidate in research field of bio-medical science/technology applications. Surface modified/functionalized CNTs and graphene derivatives materials integrated with pharmaceutical agents has been developed for the purpose of cancer therapy, antibacterial action, pathogens bio detection, drug and gene delivery. Surface modification or functionalization of CNT/graphene materials provides good platform for pharmaceutical agents attachment with improved surface Raman scattering, fluorescence and its quenching capability. Graphene-based biosensing and bioimaging technologies are widely applied to identify numerous trace level analytes. These fluorescent and electrochemical sensors are utilized primarily for detecting organic, inorganic, and biomolecules. In this article, we highlights and summarized overview of the current research progress concerned on the CNTs/graphene-based materials as a new generation materials for detection and treatment of diseases.

Carbon-Based Nanomaterials as Drug Delivery Agents for Colorectal Cancer: Clinical Preface to Colorectal Cancer Citing Their Markers and Existing Theranostic Approaches

Colorectal cancer (CRC) is one of the universally established cancers with a higher incidence rate. Novel progression toward cancer prevention and cancer care among countries in transition should be considered seriously for controlling CRC. Hence, several cutting edge technologies are ongoing for high performance cancer therapeutics over the past few decades. Several drug-delivery systems of the nanoregime are relatively new in this arena compared to the previous treatment modes such as chemo- or radiotherapy to mitigate cancer. Based on this background, the epidemiology, pathophysiology, clinical presentation, treatment possibilities, and theragnostic markers for CRC were revealed. Since the use of carbon nanotubes (CNTs) for the management of CRC has been less studied, the present review analyzes the preclinical studies on the application of carbon nanotubes for drug delivery and CRC therapy owing to their inherent properties. It also investigates the toxicity of CNTs on normal cells for safety testing and the clinical use of carbon nanoparticles (CNPs) for tumor localization. To conclude, this review recommends the clinical application of carbon-based nanomaterials further for the management of CRC in diagnosis and as carriers or therapeutic adjuvants.

Carbon-based nanostructures for cancer therapy and drug delivery applications

Synthesis, design, characterization, and application of carbon-based nanostructures (CBNSs) as drug carriers have attracted a great deal of interest over the past half of the century because of their promising chemical, thermal, physical, optical, mechanical, and electrical properties and their structural diversity. CBNSs are well-known in drug delivery applications due to their unique features such as easy cellular uptake, high drug loading ability, and thermal ablation. CBNSs, including carbon nanotubes, fullerenes, nanodiamond, graphene, and carbon quantum dots have been quite broadly examined for drug delivery systems. This review not only summarizes the most recent studies on developing carbon-based nanostructures for drug delivery (e.g. delivery carrier, cancer therapy and bioimaging), but also tries to deal with the challenges and opportunities resulting from the expansion in use of these materials in the realm of drug delivery. This class of nanomaterials requires advanced techniques for synthesis and surface modifications, yet a lot of critical questions such as their toxicity, biodistribution, pharmacokinetics, and fate of CBNSs in biological systems must be answered.

Carbon Nanotubes as Carriers in Drug Delivery for Non-Small Cell Lung Cancer, Mechanistic Analysis of Their Carcinogenic Potential, Safety Profiling and Identification of Biomarkers

Non-small cell lung cancer (NSCLC) is a global burden leading to millions of deaths worldwide every year. Nanomedicine refers to the use of materials at the nanoscale for drug delivery and subsequent therapeutic approaches in cancer. Carbon nanotubes (CNTs) are widely used as nanocarriers for therapeutic molecules such as plasmids, siRNAs, antisense agents, aptamers and molecules related to the immunotherapy for several cancers. They are usually functionalized and loaded with standard drug molecules to improve their therapeutic efficiency. Functionalization and drug loading possibly decrease the genotoxic and carcinogenic potential of CNTs. In addition, the targeted cytotoxic properties of the drug improve and undesired toxicity decreases after drug loading and/or conjugation with proteins, including antibodies. For intended drug delivery, a lysosomal pH of 5.5 is more suitable and effective for the slow and extended release of cytotoxic drugs than a physiological of pH 7.4. Remarkably, CNTs possess intrinsic antitumor properties and are usually internalized by endocytosis. After being internalized, several mechanisms are involved in the therapeutic and carcinogenic effects of CNTs. They are generally safe for therapy, and their toxicity profile remains dependent on their physicochemical properties. Moreover, the dose, route, duration of exposure, surface properties and degradative potential determine the toxicity outcomes of CNTs locally or systemically. In summary, the use of CNTs in drug delivery and NSCLC therapy, as well as their genotoxic and carcinogenic potential and the possible mechanisms, has been discussed in this review. The therapeutic index is generally high for NSCLC cells treated with drug-loaded CNTs; therefore, they are effective carriers in implementing targeted therapy for NSCLC.

Synergistic ferroptosis-gemcitabine chemotherapy of the gemcitabine loaded carbonaceous nanozymes to enhance the treatment and magnetic resonance imaging monitoring of pancreatic cancer

Pancreatic adenocarcinoma (PDAC) is one of the deadliest cancers, and it is resistant to most conventional antineoplastic therapies. To address this challenge, gemcitabine (Gem)-loaded carbonaceous nanoparticles (MFC-Gem) as nanozymes and a theranostic platform were fabricated and used for MR-guided ferroptosis-chemo synergetic therapy of PDAC. As a biocompatible carrier, MFC-Gem nanoparticles are regarded as peroxidase-like and glutathione peroxidase-like nanozymes that promote ferroptosis therapy by effectively generating ROS and consuming GSH. Meanwhile, the combination of MnFe2O4 and Gem can markedly enhance synergetic therapy by both ferroptosis and Gem chemotherapy. MFC-Gem has higher magnetic susceptibility and was used for simultaneous magnetic resonance imaging (MRI) monitoring of the PDAC treatment. In conclusion, these salient features unequivocally indicate that this biocompatible nanotheranostic system has cooperative and enhancing chemotherapy effects for anti-PDAC therapy with simultaneous MRI monitoring. STATEMENT OF SIGNIFICANCE: Pancreatic adenocarcinoma (PDAC) is one of the deadliest cancers, and it is resistant to most conventional antineoplastic therapies. To address this challenge, gemcitabine (Gem)-loaded carbonaceous nanoparticles (MFC-Gem) as nanozymes and a theranostic platform were fabricated and used for MR-guided ferroptosis-chemo synergetic therapy of PDAC. i) MFC nanoparticles are regarded as peroxidase-like and glutathione peroxidase-like nanozymes that enhance ferroptosis therapy by effectively generating ROS and consuming GSH. ii) The combination of MnFe2O4 and Gem can markedly enhance synergetic therapy by both ferroptosis and Gem chemotherapy. iii) MFC-Gem has higher magnetic susceptibility and was used for simultaneous magnetic resonance imaging (MRI) monitoring of the PDAC treatment.

Microemulsion Based Nanostructures for Drug Delivery

Most of the active pharmaceutical compounds are often prone to display low bioavailability and biological degradation represents an important drawback. Due to the above, the development of a drug delivery system (DDS) that enables the introduction of a pharmaceutical compound through the body to achieve a therapeutic effect in a controlled manner is an expanding application. Henceforth, new strategies have been developed to control several parameters considered essential for enhancing delivery of drugs. Nanostructure synthesis by microemulsions (ME) consist of enclosing a substance within a wall material at the nanoscale level, allowing to control the size and surface area of the resulting particle. This nanotechnology has shown the importance on targeted drug delivery to improve their stability by protecting a bioactive compound from an adverse environment, enhanced bioavailability as well as controlled release. Thus, a lower dose administration could be achieved by minimizing systemic side effects and decreasing toxicity. This review will focus on describing the different biocompatible nanostructures synthesized by ME as controlled DDS for therapeutic purposes.

Composite Inks for Extrusion Printing of Biological and Biomedical Constructs

Extrusion-based three-dimensional (3D) printing is an emerging technology for the fabrication of complex structures with various biological and biomedical applications. The method is based on the layer-by-layer construction of the product using a printable ink. The material used as the ink should possess proper rheological properties and desirable performances. Composite materials, which are extensively used in 3D printing applications, can improve the printability and offer superior performances for the printed constructs. Herein, we review composite inks with a focus on composite hydrogels. The properties of different additives including fibers and nanoparticles are discussed. The performances of various composite inks in biological and biomedical systems are delineated through analyzing the synergistic effects between the composite ink components. Different applications, including tissue engineering, tissue model engineering, soft robotics, and four-dimensional printing, are selected to demonstrate how 3D-printable composite inks are exploited to achieve various desired functionality. This review finally presents an outlook of future perspectives on the design of composite inks.

Biotinylated Mn3O4 nanocuboids for targeted delivery of gemcitabine hydrochloride to breast cancer and MRI applications

Multifunctional nanocarriers have been found as potential candidate for the targeted drug delivery and imaging applications. Herein, we have developed a biocompatible and pH-responsive manganese oxide nanocuboid system, surface modified with poly (ethylene glycol) bis(amine) and functionalized with biotin (Biotin-PEG-MNCs), for an efficient and targeted delivery of an anticancer drug (gemcitabine, GEM) to the human breast cancer cells. GEM-loaded Biotin-PEG@MNCs showed high drug loading efficiency, controlled release of GEM and excellent storage stability in the physiological buffers and different temperature conditions. GEM-loaded Biotin-PEG@MNCs showed dose- and time-dependent decrease in the viability of human breast cancer cells. Further, it exhibited significantly higher cell growth inhibition than pure GEM which suggested that Biotin-PEG@MNCs has efficiently delivered the GEM into cancerous cells. The role of biotin in the uptake was proved by the competitive binding-based cellular uptake study. A significant decrease in the amount of manganese was observed in biotin pre-treated cancer cells as compared to biotin untreated cancer cells. In MRI studies, Biotin-PEG-MNCs showed both longitudinal and transverse relaxivity about 0.091 and 7.66 mM^-1 s^-1 at 3.0 T MRI scanner, respectively. Overall, the developed Biotin-PEG-MNCs presents a significant potential in formulation development for cancer treatment via targeted drug delivery and enhanced MRI contrast imaging properties.

Carbon Nanotubes: Smart Drug/Gene Delivery Carriers

The unique properties of carbon nanotubes (CNTs) (such as their high surface to volume ratios, enhanced conductivity and strength, biocompatibility, ease of functionalization, optical properties, etc.) have led to their consideration to serve as novel drug and gene delivery carriers. CNTs are effectively taken up by many different cell types through several mechanisms. CNTs have acted as carriers of anticancer molecules (including docetaxel (DTX), doxorubicin (DOX), methotrexate (MTX), paclitaxel (PTX), and gemcitabine (GEM)), anti-inflammatory drugs, osteogenic dexamethasone (DEX) steroids, etc. In addition, the unique optical properties of CNTs have led to their use in a number of platforms for improved photo-therapy. Further, the easy surface functionalization of CNTs has prompted their use to deliver different genes, such as plasmid DNA (PDNA), micro-RNA (miRNA), and small interfering RNA (siRNA) as gene delivery vectors for various diseases such as cancers. However, despite all of these promises, the most important continuous concerns raised by scientists reside in CNT nanotoxicology and the environmental effects of CNTs, mostly because of their non-biodegradable state. Despite a lack of widespread FDA approval, CNTs have been studied for decades and plenty of in vivo and in vitro reports have been published, which are reviewed here. Lastly, this review covers the future research necessary for the field of CNT medicine to grow even further.

Advances in Drug Delivery Nanosystems Using Graphene-Based Materials and Carbon Nanotubes

Carbon is one of the most abundant elements on Earth. In addition to the well-known crystallographic modifications such as graphite and diamond, other allotropic carbon modifications such as graphene-based nanomaterials and carbon nanotubes have recently come to the fore. These carbon nanomaterials can be designed to help deliver or target drugs more efficiently and to innovate therapeutic approaches, especially for cancer treatment, but also for the development of new diagnostic agents for malignancies and are expected to help combine molecular imaging for diagnosis with therapies. This paper summarizes the latest designed drug delivery nanosystems based on graphene, graphene quantum dots, graphene oxide, reduced graphene oxide and carbon nanotubes, mainly for anticancer therapy.

The Applications of Carbon Nanotubes in the Diagnosis and Treatment of Lung Cancer: A Critical Review

The importance of timely diagnosis and the complete treatment of lung cancer for many people with this deadly disease daily increases due to its high mortality. Diagnosis and treatment with helping the nanoparticles are useful, although they have reasonable harms. This article points out that the side effects of using carbon nanotube (CNT) in this disease treatment process such as inflammation, fibrosis, and carcinogenesis are very problematic. Toxicity can reduce to some extent using the techniques such as functionalizing to proper dimensions as a longer length, more width, and greater curvature. The targeted CNT sensors can be connected to various modified vapors. In this regard, with helping this method, screening makes non-invasive diagnosis possible. Researchers have also found that nanoparticles such as CNTs could be used as carriers to direct drug delivery, especially with chemotherapy drugs. Most of these carriers were multi-wall carbon nanotubes (MWCNT) used for cancerous cell targeting. The results of laboratory and animal researches in the field of diagnosis and treatment became very desirable and hopeful. The collection of researches summarized has highlighted the requirement for a detailed assessment which includes CNT dose, duration, method of induction, etc., to achieve the most controlled conditions for animal and human studies. In the discussion section, 4 contradictory issues are discussed which are invited researchers to do more research to get clearer results.

Synthetic strategies in construction of organic macromolecular carrier-drug conjugates

Many metabolic inhibitors, considered potential antimicrobial or anticancer drug candidates, exhibit very limited ability to cross the biological membranes of target cells. The restricted cellular penetration of those molecules is often due to their highhydrophilicity. One of the possible solutions to this problem is a conjugation of an inhibitor with a molecular organic nanocarrier. The conjugate thus formed should be able to penetrate the membrane(s) by direct translocation, endocytosis or active transport mechanisms and once internalized, the active component could reach its intracellular target, either after release from the conjugate or in an intact form. Several such nanocarriers have been proposed so far, including macromolecular systems, carbon nanotubes and dendrimers. Herein, we present a comprehensive review of the current status of rational design and synthesis of macromolecular organic nanocarrier-drug conjugates, with special attention focused on the mode of coupling of a nanocarrier moiety with a "cargo" molecule through linking fragments of non-cleavable or cleavable type.

Naringenin-Functionalized Multi-Walled Carbon Nanotubes: A Potential Approach for Site-Specific Remote-Controlled Anticancer Delivery for the Treatment of Lung Cancer Cells

Multi-walled carbon nanotubes functionalized with naringenin have been developed as new drug carriers to improve the performance of lung cancer treatment. The nanocarrier was characterized by Transmission Electron Microscopy (TEM), Fourier-Transform Infrared Spectroscopy (FTIR), X-ray photoelectron spectroscopy, Raman Spectroscopy, and Differential Scanning Calorimetry (DSC). Drug release rates were determined in vitro by the dialysis method. The cytotoxic profile was evaluated using the MTT assay, against a human skin cell line (hFB) as a model for normal cells, and against an adenocarcinomic human alveolar basal epithelial (A569) cell line as a lung cancer in vitro model. The results demonstrated that the functionalization of carbon nanotubes with naringenin occurred by non-covalent interactions. The release profiles demonstrated a pH-responsive behavior, showing a prolonged release in the tumor pH environment. The naringenin-functionalized carbon nanotubes showed lower cytotoxicity on non-malignant cells (hFB) than free naringenin, with an improved anticancer effect on malignant lung cells (A549) as an in vitro model of lung cancer.

A brief review concerning the latest advances in the influence of nanoparticle reinforcement into polymeric-matrix biomaterials

Nanoparticles (NPs) have been studied for a wide variety of applications, due to the elevated surface area and outstanding properties. Several types of NPs are available nowadays, each one with particular characteristics and challenges. Bionanocomposites, especially composed by polymer matrices, are gaining attention in the biomedical field. Although, several studies have shown the potential of adding NPs into these materials, some investigation is still needed until their clinical use for in vivo application is consummated. Besides that, is essential to evaluate whether the addition of nanoparticles changes the matrix property. In this review, we summarize the latest advances concerning polymeric bionanocomposites incorporated with organic (polymeric, cellulosic, carbon-based), and inorganic (metallic, magnetics, and metal oxide) NPs.

When polymers meet carbon nanostructures: expanding horizons in cancer therapy

The development of hybrid materials, which combine inorganic with organic materials, is receiving increasing attention by researchers. As a consequence of carbon nanostructures high chemical versatility, they exhibit enormous potential for new highly engineered multifunctional nanotherapeutic agents for cancer therapy. Whereas many groups are working on drug delivery systems for chemotherapy, the use of carbon nanohybrids for radiotherapy is rarely applied. Thus, nanotechnology offers a wide range of solutions to overcome the current obstacles of conventional chemo- and/or radiotherapies. Within this review, the structure and properties of carbon nanostructures (carbon nanotubes, nanographene oxide) functionalized preferentially with different types of polymers (synthetic, natural) are discussed. In short, synthesis approaches, toxicity investigations and anticancer efficacy of different carbon nanohybrids are described.

Carbon Nanotubes: An Emerging Drug Delivery Carrier in Cancer Therapeutics

BACKGROUND

The scope of nanotechnology has been extended to almost every sphere of our daily life. As a result of this, nanocarriers like Carbon Nanotubes (CNTs) are gaining considerable attention for their use in various therapeutic and diagnostic applications.

OBJECTIVE

The objective of the current article is to review various important features of CNTs that make them as efficient carriers for anticancer drug delivery in cancer therapeutics.

METHODS

In this review article, different works of literature are reported on various prospective applications of CNTs in the targeting of multiple kinds of cancerous cells of different organs via; the loading of various anticancer agents.

RESULTS

Actually, CNTs are the 3rd allotropic type of the carbon-fullerenes that are a part of the cylindrical tubular architecture. CNTs possess some excellent physicochemical characteristics and unique structural features that provide an effective platform to deliver anticancer drugs to target specific sites for achieving a high level of therapeutic effectiveness even in cancer therapeutics. For better results, CNTs are functionalized and modified with different classes of therapeutically bioactive molecules via; the formation of stable covalent bonding or by the use of supramolecular assemblies based on the noncovalent interaction(s). In recent years, the applications of CNTs for the delivery of various kinds of anticancer drugs and targeting of tumor sites have been reported by various research groups.

CONCLUSION

CNTs represent an emerging nanocarrier material for the delivery and targeting of numerous anticancer drugs in cancer therapeutics.

Nanosheet composed of gold nanoparticle/graphene/epoxy resin based on ultrasonic fabrication for flexible dopamine biosensor using surface-enhanced Raman spectroscopy

Construction of a fast, easy and sensitive neurotransmitters-based sensor could provide a promising way for the diagnosis of neurological diseases, leading to the discovery of more effective treatment methods. The current work is directed to develop for the first time a flexible Surface-Enhanced Raman Spectroscopy (SERS) based neurotransmitters sensor by using the ultrasonic-assisted fabrication of a new set of epoxy resin (EPR) nanocomposites based on graphene nanosheets (GNS) using the casting technique. The perspicuous epoxy resin was reinforced by the variable loading of GNS giving the general formula GNS/EPR1-5. The designed products have been fabricated in situ while the perspicuous epoxy resin was formed. The expected nanocomposites have been fabricated using 3%, 5%, 10%, 15% and 20% GNS loading was applied for such fabrication process. The chemical, physical and morphological properties of the prepared nanocomposites were investigated by using Fourier transforms infrared spectroscopy, X-ray diffraction, Thermogravimetric analysis, Differential Thermal gravimetry, and field emission scanning electron microscopy methods. The GNS/EPR1-5 nanocomposites were decorated with a layer of gold nanoparticles (Au NPs/GNS/EPR) to create surface-enhanced Raman scattering hot points. The wettability of the Au NPs/GNS/EPR was investigated in comparison with the different nanocomposites and the bare epoxy. Au NPs/GNS/EPR was used as a SERS-active surface for detecting different concentrations of dopamine with a limit of detection of 3.3 µM. Our sensor showed the capability to detect low concentrations of dopamine either in a buffer system or in human serum as a real sample.

Recent advances in the use of carbon nanotubes as smart biomaterials

Carbon nanotubes (CNTs) have remarkable mechanical, thermal, electronic, and biological properties due to their particular atomic structure made of graphene sheets that are rolled into cylindrical tubes. Due to their outstanding properties, CNTs have been used in several technological fields. Currently, the most prominent research area of CNTs focuses on biomedical applications, using these materials to produce hybrid biosensors, drug delivery systems, and high performance composites for implants. Although a great number of research studies have already shown the advantages of CNT-based biomedical devices, their clinical use for in vivo application has not been consummated. Concerns related to their toxicity, biosafety, and biodegradation still remain. The effect of CNTs on the human body and the ecosystem is not well established, especially due to the lack of standardization of toxicological tests, which generate contradictions in the results. CNTs' toxicity must be clarified to enable the medical use of these exceptional materials in the near future. In this review, we summarize recent advances in developing biosensors, drug delivery systems, and implants using CNTs as smart biomaterials to identify pathogens, load/deliver drugs and enhance the mechanical and antimicrobial performance of implants.

Hyaluronic acid conjugated multi-walled carbon nanotubes for colon cancer targeting

Purpose of the present research was to evaluate in vitro and in vivo potential of gemcitabine (GEM) loaded hyaluronic acid (HA) conjugated PEGylated multi-walled carbon nanotubes (GEM/HA-PEG-MWCNTs) for effective colon cancer targeting. HA was conjugated onto the surface of aminated or PEGylated MWCNTs which were evaluated for size, surface morphology, entrapment efficiency (~90%), in vitro drug release, in vitro cytotoxicity and in vivo performance in Sprague Dawley rats. In vitro release showed that the release rate of GEM in acidic conditions (pH 5.3) was faster than physiological conditions (PBS, pH 7.4) followed by a sustained release pattern. The developed GEM/HA-PEG-MWCNTs indicated significantly less hemolytic toxicity (7.73 ± 0.4%) paralleled to free GEM (18.71 ± 0.44%) and showed higher cytotoxicity against HT-29 colon cancer cell line. The antitumor study assured that GEM/HA-PEG-MWCNTs significantly reduced tumor volume as compared to free GEM and increased survival rate without noticeable loss in body weight. In vivo studies showed an improvement in pharmacokinetics in terms of remarkable escalation in mean residence time, half-life, AUC, AUMC, median survival time in tumor bearing rats treated with GEM/HA-MWCNTs and GEM/HA-PEG-MWCNTs as compared to free GEM (p ˂ 0.001). These outcomes proved engineered MWCNTs as a safe and effective nanomedicine in colon cancer targeting.

The Yin and Yang of carbon nanomaterials in atherosclerosis

With unique characteristics such as high surface area, capacity of various functionalization, low weight, high conductivity, thermal and chemical stability, and free radical scavenging, carbon nanomaterials (CNMs) such as carbon nanotubes (CNTs), fullerene, graphene (oxide), carbon nanohorns (CNHs), and their derivatives have increasingly been utilized in nanomedicine and biomedicine. On the one hand, owing to ever-increasing applications of CNMs in technological and industrial fields as well as presence of combustion-derived CNMs in the ambient air, the skepticism has risen over the adverse effects of CNMs on human being. The influences of CNMs on cardiovascular system and cardiovascular diseases (CVDs) such as atherosclerosis, of which consequences are ischemic heart disease and ischemic stroke, as the main causes of death, is of paramount importance. In this regard, several studies have been devoted to specify the biomedical applications and cardiovascular toxicity of CNMs. Therefore, the aim of this review is to specify the roles and applications of various CNMs in atherosclerosis, and also identify the key role playing parameters in cardiovascular toxicity of CNMs so as to be a clue for prospective deployment of CNMs.

Preliminary study on conjugation of formononetin with multiwalled carbon nanotubes for inducing apoptosis via ROS production in HeLa cells

Background

The present work was conducted to prepare and evaluate multiwalled carbon nanotube–formononetin (MWCNT-FMN) composite for sustained delivery and inducing apop-tosis via reactive oxygen species (ROS) production in HeLa cells.

Methods

The composite was prepared by solution mixing with short carboxylic group-functionalized multiwalled carbon nanotubes (MWCNT-COOH). Then the composite was characterized by laser particle size analysis, Fourier transform infrared spectrometry, X-ray diffractometry, differential scanning calorimetry, and scanning electron microscopy. Drug release rates in vitro were determined by dialysis method. The in vitro cytotoxicity study was performed using water soluble tetrazolium assay. The cellular apoptosis assay, ROS, and mitochondrial membrane potential (MMP) of HeLa cells were investigated by acridine orange and ethidium bromide double dye, 2′,7′-dichlorodihydrofluorescein diacetate, and 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethyl-imidacarbocyanine iodide probe, respectively.

Results

The entrapment efficiency was 28.77%±0.15%, and the loading capacity was 12.05%±0.20%. The release of MWCNT-FMN was sustained, and the cumulative release rate of formononetin (FMN) from MWCNT-COOH was higher at pH 7.4 than at pH 5.3. The in vitro cytotoxicity assay demonstrated that FMN, MWCNT-COOH, and MWCNT-FMN had no significant effects on the proliferation and viability of mouse fibroblast 3T3 cells over 48 hours, while the cell growth inhibition of the three samples showed concentration-dependent for HeLa cells. Biological assay suggested FMN and MWCNT-FMN could induce apoptosis in HeLa cells, meanwhile the cells exhibited stronger ROS signal and more depolarized MMP than that of the control group.

Conclusion

These results preliminarily demonstrated that MWCNT-FMN exerted anticancer efficacy through cellular apoptosis induced by ROS-mediated mitochondrial dysfunctions in HeLa cells.

Functionalized carbon nanotubes as emerging delivery system for the treatment of cancer

In recent time, carbon nanotubes (CNTs) have gained vital importance for pharmaceutical formulation scientist for delivering drugs and genes, owing to their excellent surface properties. For example, their aspect ratio is thought to be responsible for their excellent cell penetration aptitude; anisotropic conductivity/semi-conductivity along their axis is ideal for integration with nervous and muscular tissue; an ultrahigh surface area maximizes their ability to "talk" with biological matter; the hollow interior provides an enormous cargo-carrying capacity for drug delivery; and their exteriors are readily functionalized to permit tailoring of solubility and biological recognition. Despite their immense capabilities for the delivery of drugs, genes and other biomedically essential materials, there use is restricted primarily because of the severe toxicity. However, the reactive nature of the surface of the CNTs allowed attaching the guest molecules (drug, siRNA, and diagnostics) of interest which helps in increasing the biocompatibility of these novel nanocarriers. As per the need, CNTs can be modified with peptides, organic molecules, carbohydrates, polymers and used mainly for cancer targeting and tumor cell accumulation. This review expounds different functionalization strategies employed for CNTs that created new opportunities for scientists to improve the potential of delivered therapeutics.

Dexamethasone-Loaded, PEGylated, Vertically Aligned, Multiwalled Carbon Nanotubes for Potential Ischemic Stroke Intervention

The complete synthesis, optimization, purification, functionalization and evaluation of vertically aligned multiwalled carbon nanotubes (VA-MWCNTs) was reported for potential application in dexamethasone delivery to the ischemic brain tissue. The conditions for high yield were optimized and carbon nanotubes functionalized and PEGylated prior to dexamethasone loading. Morphological changes were confirmed by SEM and TEM. Addition of functional groups to MWCNTs was demonstrated by FTIR. Thermal stability reduced following MWCNTs functionalization as demonstrated in TGA. The presence of carbon at 2θ of 25° and iron at 2θ of 45° in MWCNTs was illustrated by XRD. Polydispersive index and zeta potential were found to be 0.261 and −15.0 mV, respectively. Dexamethasone release increased by 55%, 65% and 95% in pH of 7.4, 6.5 and 5.5 respectively as evaluated by UV-VIS. The functionalized VA-MWCNTs were demonstrated to be less toxic in PC-12 cells in the concentration range from 20 to 20,000 µg/mL. These findings have demonstrated the potential of VA-MWCNTs in the enhancement of fast and prolonged release of dexamethasone which could lead to the effective treatment of ischemic stroke. More work is under way for targeting ischemic sites using atrial natriuretic peptide antibody in stroke rats.

A carbon nanotube-gemcitabine-lentinan three-component composite for chemo-photothermal synergistic therapy of cancer

PURPOSE

Gemcitabine's clinical application is limited due to its short plasma half-life and poor uptake by cells. To address this problem, a drug delivery three-component composite, multiwalled carbon nanotubes (MWNTs)/gemcitabine (Ge)/lentinan (Le; MWNTs-Ge-Le), was fabricated in our study. Moreover, the combination of chemotherapy and photothermal therapy was employed to enhance antitumor efficacy.

METHODS

In this study, we conjugated gemcitabine and lentinan with MWNTs via a covalent and noncovalent way to functionalize with MWNTs, and the chemical structure of MWNTs-Ge-Le was characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis and transmission electron microscopy. Using the composite and an 808 nm laser, we treated tumors, both in vitro and in vivo, and investigated the photothermal responses and the anticancer efficacy.

RESULTS

The MWNTs-Ge-Le composite could efficiently cross cell membrane, having a higher antitumor activity than MWNTs, gemcitabine and MWNTs-Ge in vitro and in vivo. Our study on the MWNTs-Ge-Le composite with an 808 nm laser radiation showed the combination of drug therapy and near-infrared photothermal therapy possesses great synergistic antitumor efficacy.

CONCLUSION

The MWNTs-Ge-Le three-component anticancer composite can serve as a promising candidate for cancer therapy in the combination of chemotherapy and photothermal therapy.

Fabrication of EPYR/GNP/MWCNT carbon-based composite materials for promoted epoxy coating performance

The present study is aimed to fabricate composite materials containing epoxy resin (EPYR) reinforced by mixed carbon-based nano-fillers in the form of graphene nano-platelet (GNP) and multi-walled carbon nanotube (MWCNT) using the dissolution casting technique with the help of ultrasonic assistance. The pure epoxy resin was reinforced by variable loading of mixed GNP/MWCNT in situ, and the epoxy resin is denoted as EPYR/GNP/MWCNT_2–30. The numbers 2–30 corresponded to the final mass ratio of the nano-fillers. The designed products were reinforced by variable percentages of GNP/MWCNTs. XRD, FT-IR, thermal analyses, FE-SEM, TEM and electrical conductivity were utilized as identification techniques to confirm the structures of these composite materials. An excellent evidence for the composite formation was given by XRD diffraction patterns and FT-IR spectroscopy. The introduced amounts of mixed nano-fillers showed significant effects on the thermal, conducting and coating behaviors of pure EPYR. Pure EPYR and EPYR/GNP/MWCNT_20,30 showed higher thermal stabilities than other materials in the range of 400–410 °C. EPYR/GNP/MWCNT₂₀ also showed remarkable increase in the thermal stability compared to other materials. T₁₀ represents the temperatures at which 10% weight losses are examined. Pure EPYR and its related EPYR/GNP/MWCNT_2–30 displayed similar thermal stabilities at T₁₀ temperature (330 ± 4 °C). The morphological features were examined by SEM and TEM; these features showed that the nanocomposite components were extremely compatible. The in situ electrical conductivity values showed noticeable enhancement for the formulations of EPYR/GNP/MWCNT_2–10. Moreover, the coating performance of EPYR was tested by water uptake experiments and electrochemical impedance; both tests proved that the mixed GNP/MWCNT nano-fillers remarkably improved the pure EPYR coating due to the ionic charge transfer resistance and elevated barrier behaviour. The coating resistance variations values (CRv) of EPYR/GNP/MWCNT₁₀ were the highest among the measured composition values, closely followed by those of EPYR/GNP/MWCNT₂₀ and EPYR/GNP/MWCNT₃₀.

Composite materials containing epoxy resin and reinforced by mixed carbon-based nano-fillers (GNP/MWCNT) have been fabricated using the dissolution casting technique with the help of ultrasonic assistance for promoted epoxy coating performance.

Biophysical interactions between pancreatic cancer cells and pristine carbon nanotube substrates: Potential application for pancreatic cancer tissue engineering

Novel synthetic biomaterials able to support direct tissue growth and retain cellular phenotypical properties are promising building blocks for the development of tissue engineering platforms for accurate and fast therapy screening for cancer. The aim of this study is to validate an aligned, pristine multi-walled carbon nanotube (CNT) platform for in vitro studies of pancreatic cancer as a systematic understanding of interactions between cells and these CNT substrates is lacking. Our results demonstrate that our CNT scaffolds-which are easily tuneable to form sheets/fibers-support growth, proliferation, and spatial organization of pancreatic cancer cells, indicating their great potential in cancer tissue engineering. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1637-1644, 2018.