Fabrication of chlorambucil loaded graphene- oxide nanocarrier and its application for improved antitumor activity

Delivery of Chlorambucil to the Brain Using Surface Modified Solid Lipid Nanoparticles

The delivery of drugs to the brain in the therapy of diseases of the central nervous system (CNS) remains a continuing challenge because of the lack of delivery systems that can cross the blood-brain barrier (BBB). Therefore, there is a need to develop an innovative delivery method for the treatment of CNS diseases. Thus, we have investigated the interaction of γ-aminobutyric acid (GABA) and S-(-)-γ-amino-α-hydroxybutyric acid (GAHBA) with the GABA receptor by performing a docking study. Both GABA and GAHBA show comparable binding affinities toward the receptor. In this study, we developed surface-modified solid lipid nanoparticles (SLNs) using GAHBA-derived lipids that can cross the BBB. CLB-loaded SLNs were characterized by a number of methods including differential scanning calorimetry, dynamic light scattering, UV-vis spectroscopy, and transmission electron microscopy. The blank and CLB-loaded SLN suspensions were found to exhibit good storage stability. Also, the SLNs showed a higher encapsulation efficiency for CLB drugs. In vitro release kinetics of CLB at physiological temperature was also investigated. The results of the in vitro cell cytotoxicity assay and flow cytometry studies in the human glioma U87MG cell line and human prostate cancer PC3 cell line suggested a higher efficacy of the GAHBA-modified CLB-loaded SLNs in U87MG cells. The transcription level of GABA receptor expression in the target organ and cell line was analyzed by a reverse transcription polymerase chain reaction study. The in vivo biodistribution and brain uptake in C57BL6 mice and SPECT/CT imaging in Wistar rats investigated using 99mTc-labeled SLN and autoradiography suggest that the SLNs have an increasing brain uptake. We have demonstrated the delivery of the anticancer drug chlorambucil (CLB) to glioma.

Rhodamine B-Conjugated Fluorescent Block Copolymer Micelles for Efficient Chlorambucil Delivery and Intracellular Imaging

The clinical development of the anticancer drug chlorambucil (CHL) is limited by its low solubility in water, poor bioavailability, and off-target toxicity. Besides, another constraint for monitoring intracellular drug delivery is the non-fluorescent nature of CHL. Nanocarriers based on block copolymers of poly(ethylene glycol)/poly(ethylene oxide) (PEG/PEO) and poly(ε-caprolactone) (PCL) are an elegant choice for drug delivery applications due to their high biocompatibility and inherent biodegradability properties. Here, we have designed and prepared block copolymer micelles (BCM) containing CHL (BCM-CHL) from a block copolymer having fluorescent probe rhodamine B (RhB) end-groups to achieve efficient drug delivery and intracellular imaging. For this purpose, the previously reported tetraphenylethylene (TPE)-containing poly(ethylene oxide)-b-poly(ε-caprolactone) [TPE-(PEO-b-PCL)₂] triblock copolymer was conjugated with RhB by a feasible and effective post-polymerization modification method. In addition, the block copolymer was obtained by a facile and efficient synthetic strategy of one-pot block copolymerization. The amphiphilicity of the resulting block copolymer TPE-(PEO-b-PCL-RhB)₂ led to the spontaneous formation of micelles (BCM) in aqueous media and successful encapsulation of the hydrophobic anticancer drug CHL (CHL-BCM). Dynamic light scattering and transmission electron microscopy analyses of BCM and CHL-BCM revealed a favorable size (10-100 nm) for passive targeting of tumor tissues via the enhanced permeability and retention effect. The fluorescence emission spectrum (λ_ex 315 nm) of BCM demonstrated Förster resonance energy transfer between TPE aggregates (donor) and RhB (acceptor). On the other hand, CHL-BCM revealed TPE monomer emission, which may be attributed to the π-π stacking interaction between TPE and CHL molecules. The in vitro drug release profile showed that CHL-BCM exhibits drug release in a sustained manner over 48 h. A cytotoxicity study proved the biocompatibility of BCM, while CHL-BCM revealed significant toxicity to cervical (HeLa) cancer cells. The inherent fluorescence of RhB in the block copolymer offered an opportunity to directly monitor the cellular uptake of the micelles by confocal laser scanning microscopy imaging. These results demonstrate the potential of these block copolymers as drug nanocarriers and as bioimaging probes for theranostic applications.

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.

Graphene family in cancer therapy: recent progress in cancer gene/drug delivery applications

In the past few years, the development in the construction and architecture of graphene based nanocomplexes has dramatically accelerated the use of nano-graphene for therapeutic and diagnostic purposes, fostering a new area of nano-cancer therapy. To be specific, nano-graphene is increasingly used in cancer therapy, where diagnosis and treatment are coupled to deal with the clinical difficulties and challenges of this lethal disease. As a distinct family of nanomaterials, graphene derivatives exhibit outstanding structural, mechanical, electrical, optical, and thermal capabilities. Concurrently, they can transport a wide variety of synthetic agents, including medicines and biomolecules, such as nucleic acid sequences (DNA and RNA). Herewith, we first provide an overview of the most effective functionalizing agents for graphene derivatives and afterward discuss the significant improvements in the gene and drug delivery composites based on graphene.

Chlorambucil-Loaded Graphene-Oxide-Based Nano-Vesicles for Cancer Therapy

In this study, the authors have designed biocompatible nano-vesicles using graphene oxide (GO) for the release of chlorambucil (CHL) drugs targeting cancerous cells. The GO sheets were first sulfonated and conjugated with folic acid (FA) molecules for controlled release and high loading efficiency of CHL. The chlorambucil (CHL) drug loading onto the functionalized GO surface was performed through π-π stacking and hydrophobic interactions with the aromatic planes of GO. The drug loading and "in vitro" release from the nano-vesicles at different pH were studied. The average particle size, absorption, and loading efficiency (%) of FA-conjugated GO sheets (CHL-GO) were observed to be 300 nm, 58%, and 77%, respectively. The drug release study at different pH (i.e., 7.4 and 5.5) showed a slight deceleration at pH 7.4 over pH 5.5. The amount of drug released was very small at pH 7.4 in the first hour which progressively increased to 24% after 8 h. The rate of drug release was faster at pH 5.5; initially, 16% to 27% in the first 3 h, and finally it reached 73% after 9 h. These observations indicate that the drug is released more rapidly at acidic pH with a larger amount of drug-loading ability. The rate of drug release from the CHL-loaded GO was 25% and 75% after 24 h. The biotoxicity study in terms of % cell viability of CHL-free and CHL-loaded GO against human cervical adenocarcinoma cell line was found to have lower cytotoxicity of CHL-loaded nano-vesicles (IC₅₀ = 18 μM) as compared to CHL-free (IC₅₀ = 8 μM). It is concluded that a high drug-loading efficiency and controlled release with excellent biotoxicity of CHL-GO offers an excellent application in the biomedical field.

Construction of nano slow-release systems for antibacterial active substances and its applications: A comprehensive review

At present, nano-carrier materials with antibacterial activity are of great significance. Due to the widespread resistance of many pathogenic microorganisms, it has seriously threatened human health. The natural antimicrobial substances extracted from fruits and vegetables can significantly improve their stability combined with nano-carrier materials. The resistance of pathogenic microorganisms will be substantially reduced, greatly enhancing the effect of active antimicrobial substances. Nanotechnology has excellent research prospects in the food industry, antibacterial preservation, food additives, food packaging, and other fields. This paper introduces nano-carrier materials and preparation techniques for loading and encapsulating active antibacterial substances in detail by constructing a nano-release system for active antibacterial substances. The antibacterial effect can be achieved by protecting them from adverse external conditions and destroying the membrane of pathogenic microorganisms. The mechanism of the slow release of the bacteriostatic active substance is also described. The mechanism of carrier loading and release is mainly through non-covalent forces between the bacteriostatic active substance and the carrier material, such as hydrogen bonding, π-π stacking, van der Waals forces, electrostatic interactions, etc., as well as the loading and adsorption of the bacteriostatic active substance by the chemical assembly. Finally, its wide application in food and medicine is introduced. It is hoped to provide a theoretical basis and technical support for the efficient utilization and product development of bacteriostatic active substances.

Platelet-biomimetic nanoparticles for in vivo targeted photodynamic therapy of breast cancer

Nanocarrier-based photodynamic therapy (PDT) has emerged as a promising treatment in cancer therapy. However, the PDT therapeutic efficacy is limited by the lack of specificity, limited intracellular cytotoxic reactive oxygen species (ROS) generation, and the immunosuppressive tumor microenvironment. Herein, a platelet membrane (Pm) decorated and chlorin e6 loaded liposome (Pm/Lps/Ce6) is developed to improve specific tumor-targeting capability and antitumor responses. Pm/Lps/Ce6 could efficiently improve the cellular internalization of Ce6. Under 660-nm laser irradiation, enough ROS was produced to suppress the growth of tumor cells in vitro. In vivo, the Pm decoration increased cellular uptake of the Ce6 loaded liposome in cancer cells by the tumor-targeting and immune escape capacity and produced a satisfactory inhibitory effect on breast cancer. Our study provides a biomimetic strategy via the biological properties of Pm to improve the antitumor performance of photodynamic therapy for treating breast cancer.

Biomedical applications of metallic nanoparticles in cancer: Current status and future perspectives

The current advancements in nanotechnology are as an outcome of the development of engineered nanoparticles. Various metallic nanoparticles have been extensively explored for various biomedical applications. They attract lot of attention in biomedical field due to their significant inert nature, and nanoscale structures, with size similar to many biological molecules. Their intrinsic characteristics which include electronic, optical, physicochemical and, surface plasmon resonance, that can be changed by altering certain particle characteristics such as size, shape, environment, aspect ratio, ease of synthesis and functionalization properties have led to numerous applications in various fields of biomedicine. These include targeted drug delivery, sensing, photothermal and photodynamic therapy, imaging, as well as the modulation of two or three applications. The current article also discusses about the various properties of metallic nanoparticles and their applications in cancer imaging and therapeutics. The associated bottlenecks related to their clinical translation are also discussed.

Graphene and graphene oxide with anticancer applications: Challenges and future perspectives

Graphene-based materials have shown immense pertinence for sensing/imaging, gene/drug delivery, cancer therapy/diagnosis, and tissue engineering/regenerative medicine. Indeed, the large surface area, ease of functionalization, high drug loading capacity, and reactive oxygen species induction potentials have rendered graphene- (G-) and graphene oxide (GO)-based (nano)structures promising candidates for cancer therapy applications. Various techniques namely liquid-phase exfoliation, Hummer's method, chemical vapor deposition, chemically reduced GO, mechanical cleavage of graphite, arc discharge of graphite, and thermal fusion have been deployed for the production of G-based materials. Additionally, important criteria such as biocompatibility, bio-toxicity, dispersibility, immunological compatibility, and inflammatory reactions of G-based structures need to be systematically assessed for additional clinical and biomedical appliances. Furthermore, surface properties (e.g., lateral dimension, charge, corona influence, surface structure, and oxygen content), concentration, detection strategies, and cell types are vital for anticancer activities of these structures. Notably, the efficient accumulation of anticancer drugs in tumor targets/tissues, controlled cellular uptake properties, tumor-targeted drug release behavior, and selective toxicity toward the cells are crucial criteria that need to be met for developing future anticancer G-based nanosystems. Herein, important challenges and future perspectives of cancer therapy using G- and GO-based nanosystems have been highlighted, and the recent advancements are deliberated.

The Role of Graphene Oxide Nanocarriers in Treating Gliomas

Gliomas are the most common primary malignant tumors of the central nervous system, and their conventional treatment involves maximal safe surgical resection combined with radiotherapy and temozolomide chemotherapy; however, this treatment does not meet the requirements of patients in terms of survival and quality of life. Graphene oxide (GO) has excellent physical and chemical properties and plays an important role in the treatment of gliomas mainly through four applications, viz. direct killing, drug delivery, immunotherapy, and phototherapy. This article reviews research on GO nanocarriers in the treatment of gliomas in recent years and also highlights new ideas for the treatment of these tumors.

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.

Carbon-based nanomaterials for targeted cancer nanotherapy: recent trends and future prospects

Carbon-based nanomaterials are becoming attractive materials due to their unique structural dimensions and promising mechanical, electrical, thermal, optical and chemical characteristics. Carbon nanotubes, graphene, graphene oxide, carbon and graphene quantum dots have numerous applications in diverse areas, including biosensing, drug/gene delivery, tissue engineering, imaging, regenerative medicine, diagnosis, and cancer therapy. Cancer remains one of the major health problems all over the world, and several therapeutic approaches are focussed on designing targeted anticancer drug delivery nanosystems by applying benign and less hazardous resources with high biocompatibility, ease of functionalization, remarkable targeted therapy issues, and low adverse effects. This review highlights the recent development on these carbon based-nanomaterials in the field of targeted cancer therapy and discusses their possible and promising diagnostic and therapeutic applications for the treatment of cancers.