Graphene Quantum Dots-Mediated Theranostic Penetrative Delivery of Drug and Photolytics in Deep Tumors by Targeted Biomimetic Nanosponges

Graphene Quantum Dots as Antifibrotic Therapy for Kidney Disease

Graphene quantum dots (GQDs) have received much attention for their biomedical applications, such as bioimaging and drug delivery. Additionally, they have antioxidant and anti-inflammatory properties. We used GQDs to treat renal fibrosis and confirmed their ability to protect renal cells from excessive oxidative stress in vitro and in vivo. Tubulointerstitial fibrosis was induced by unilateral ureteral obstruction (UUO) in 7- to 8-week-old male C57BL/6 mice. GQDs were administered by intravenous injection to mimic clinical treatment. The levels of oxidative stress, ROS production, apoptosis and proinflammatory cytokines and the activity of the TGFβ1/Smad pathway were evaluated after treatment with GQDs. In vitro, rhTGF-β1 was used to induce fibrosis in primary kidney tubule epithelial cells. GQDs alleviated fibrosis and morphological changes after UUO induction. At the mRNA and protein levels, GQDs significantly reduced the expression of fibrotic markers and proinflammatory cytokines, decreased ROS production and TGF-β1 expression, and affected Smad-dependent signaling pathways. In vitro, GQDs inhibited rhTGF-β1-induced epithelial-to-mesenchymal transition in primary kidney tubule epithelial cells and reduced apoptosis and ROS accumulation. This study revealed the role of GQDs in kidney fibrosis: GQDs effectively attenuated major fibrogenesis events by inhibiting ROS accumulation and the vicious cycle of the ROS and TGF-β1/Smad signaling pathways, as well as alleviating cell apoptosis and inflammation. Thus, GQDs may be a therapeutic option for chronic kidney disease progression.

Large Scale Synthesis of Carbon Dots and Their Applications: A Review

Carbon dots (CDs), a versatile class of fluorescent carbon-based nanomaterials, have attracted widespread attention due to their exceptional optical properties, biocompatibility, and cost-effectiveness. Their applications span biomedicine, optoelectronics, and smart food packaging, yet large-scale synthesis remains a significant challenge. This review categorizes large-scale synthesis methods into liquid-phase (hydrothermal/solvothermal, microwave-assisted, magnetic hyperthermia, aldol condensation polymerization), gas-phase (plasma synthesis), solid-phase (pyrolysis, oxidation/carbonization, ball milling), and emerging techniques (microfluidic, ultrasonic, molten-salt). Notably, microwave-assisted and solid-state synthesis methods show promise for industrial production due to their scalability and efficiency. Despite these advances, challenges persist in optimizing synthesis reproducibility, reducing energy consumption, and developing purification methods and quality control strategies. Addressing these issues will be critical for transitioning CDs from laboratory research to real-world applications.

Reprogrammed Lung Metastasis Immunodeficiency via Targeted Penetrated Delivery of M1 Macrophage-Wrapped NanoCubes-Mediated T Cell Infiltration

The infiltration of cytotoxic T lymphocytes holds promise for suppressing even the most resilient metastatic tumors in immunotherapy. Polarizing tumor-associated macrophages (TAMs) and remodeling the immune-deficient tumor microenvironment (TME) can enhance T lymphocyte recruitment and infiltration. However, the immune privilege and low immunogenic responses of these aggressive tumor clusters often limit lymphocyte recruitment. Here, an M1 macrophage membrane-coated iron oxide nanoparticle (IO@MM) double as a tumor-penetrated agent and naïve M0 macrophage to M1 polarizer is developed for lung metastatic colorectal cancer (CRC) immunotherapy. At the tumor site, IO@MM combined with resiquimod (R848) increased the immune cell infiltration, turning the "Cold" TME into an immune-activating "Hot" one. Together with self-cascade immunotherapy, IO@MM with R848 promotes tumor release of damage-associated molecular patterns (DAMPs). At the same time, IO@MM uses the membrane as an antigen reservoir and provides autologous DAMPs to retain dendritic cells. This IO@MM effectively inhibits tumors and improves survival rate as an immunomodulator in lung metastasis.

Photothermally Active Quantum Dots in Cancer Imaging and Therapeutics: Nanotheranostics Perspective

Cancer is becoming a global threat, as the cancerous cells manipulate themselves frequently, resulting in mutants and more abnormalities. Early-stage and real-time detection of cancer biomarkers can provide insight into designing cost-effective diagnostic and therapeutic modalities. Nanoparticle and quantum dot (QD)-based approaches have been recognized as clinically relevant methods to detect disease biomarkers at the molecular level. Over decades, as an emergent noninvasive approach, photothermal therapy has evolved to eradicate cancer. Moreover, various structures, viz., nanoparticles, clusters, quantum dots, etc., have been tested as bioimaging and photothermal agents to identify tumor cells selectively. Among them, QDs have been recognized as versatile probes. They have attracted enormous attention for imaging and therapeutic applications due to their unique colloidal stability, optical and physicochemical properties, biocompatibility, easy surface conjugation, scalable production, etc. However, a few critical concerns of QDs, viz., precise engineering for molecular imaging and sensing, selective interaction with the biological system, and their associated toxicity, restrict their potential intervention in curing cancer and are yet to be explored. According to the U.S. Food and Drug Administration (FDA), there is no specific regulation for the approval of nanomedicines. Therefore, these nanomedicines undergo the traditional drug, biological, and device approval process. However, the market survey of QDs is increasing, and their prospects in translational nanomedicine are very promising. From this perspective, we discuss the importance of QDs for imaging, sensing, and therapeutic usage pertinent to cancer, especially in its early stages. Moreover, we also discuss the rapidly growing translational view of QDs. The long-term safety studies and cellular interaction of these QDs could enhance their visibility and bring photothermally active QDs to the clinical stage and concurrently to FDA approval.

Carbon dots encapsulated zeolitic imidazolate framework-8 as an enhanced multi-antioxidant for efficient cytoprotection to HK-2 cells

Excessive reactive oxygen species (ROS) can lead to the imbalance of antioxidant system in the body and cause oxidative damage to cells. It is imperative to rationally design nanomaterials with high catalytic activity and multiple antioxidant activities. Here, line peppers-derived carbon dots (CDs) is encapsulated into zeolitic imidazolate framework-8 (CDs@ZIF-8) to achieve enhanced antioxidant activities for improved protective effect on cells. This nanosystem has a broad spectrum of antioxidant properties, which can effectively remove a variety of intracellular ROS and protect cells from ROS-induced death and cytoskeleton damage. In addition, CDs@ZIF-8 can reduce malondialdehyde (MDA) level and increase the enzyme activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx), as well as the level of glutathione (GSH) in human kidney proximal tubular epithelial cells (HK-2) cells. Mechanism studies demonstrated that CDs@ZIF-8 can up-regulate the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1), allowing the regulation of antioxidant enzymes to further achieve antioxidant effect. Besides, CDs@ZIF-8 inhibited the secretion of proinflammatory cytokines. This work demonstrates that the constructed CDs@ZIF-8 with multi-antioxidant activity can act as a highly efficient intracellular ROS scavenger and provide potential for the application in related oxidative stress-induced diseases.

Harnessing the Potential of Graphene Quantum Dots for Multifunctional Biomedical Applications

The existing and emerging demand for materials for life and health has contributed to the cultivation and development of respective markets. Nevertheless, the current generation of biomedical materials has yet to fully satisfy the clinical requirements of the market, which is still in its relative infancy. Research and development in this area must be prioritized in light of the pivotal role of new life and health materials in the biological field. Among many life and health materials, GQDs, an emerging nanomaterial, exhibit considerable promise in the biomedical field, primarily due to their exceptional properties. Furthermore, the direct preparation and functionalization of GQDs have facilitated the development of specific functional composites based on GQDs. The biological applications of GQDs are undergoing rapid growth, which makes it necessary to publish a review article presenting the latest advances in this field. This review provides an overview of the significant advances in synthesizing GQDs, the techniques employed for structural characterizations, and the properties that have been elucidated. Furthermore, it presents recent findings on applying GQDs in antimicrobial, anticancer, biosensing, drug delivery, and bioimaging applications. Finally, it explores the potential of GQDs in biomedicine and biotechnology, highlighting the current challenges that remain to be addressed.

Effect of Polymer and Cell Membrane Coatings on Theranostic Applications of Nanoparticles: A Review

The recent decade has witnessed a remarkable surge in the field of nanoparticles, from their synthesis, characterization, and functionalization to diverse applications. At the nanoscale, these particles exhibit distinct physicochemical properties compared to their bulk counterparts, enabling a multitude of applications spanning energy, catalysis, environmental remediation, biomedicine, and beyond. This review focuses on specific nanoparticle categories, including magnetic, gold, silver, and quantum dots (QDs), as well as hybrid variants, specifically tailored for biomedical applications. A comprehensive review and comparison of prevalent chemical, physical, and biological synthesis methods are presented. To enhance biocompatibility and colloidal stability, and facilitate surface modification and cargo/agent loading, nanoparticle surfaces are coated with different synthetic polymers and very recently, cell membrane coatings. The utilization of polymer- or cell membrane-coated nanoparticles opens a wide variety of biomedical applications such as magnetic resonance imaging (MRI), hyperthermia, photothermia, sample enrichment, bioassays, drug delivery, etc. With this review, the goal is to provide a comprehensive toolbox of insights into polymer or cell membrane-coated nanoparticles and their biomedical applications, while also addressing the challenges involved in translating such nanoparticles from laboratory benchtops to in vitro and in vivo applications. Furthermore, perspectives on future trends and developments in this rapidly evolving domain are provided.

Graphene Quantum Dots from Natural Carbon Sources for Drug and Gene Delivery in Cancer Treatment

Cancer therapy is constantly evolving, with a growing emphasis on targeted and efficient treatment options. In this context, graphene quantum dots (GQDs) have emerged as promising agents for precise drug and gene delivery due to their unique attributes, such as high surface area, photoluminescence, up-conversion photoluminescence, and biocompatibility. GQDs can damage cancer cells and exhibit intrinsic photothermal conversion and singlet oxygen generation efficiency under specific light irradiation, enhancing their effectiveness. They serve as direct therapeutic agents and versatile drug delivery platforms capable of being easily functionalized with various targeting molecules and therapeutic agents. However, challenges such as achieving uniform size and morphology, precise bandgap engineering, and scalability, along with minimizing cytotoxicity and the environmental impact of their production, must be addressed. Additionally, there is a need for a more comprehensive understanding of cellular mechanisms and drug release processes, as well as improved purification methods. Integrating GQDs into existing drug delivery systems enhances the efficacy of traditional treatments, offering more efficient and less invasive options for cancer patients. This review highlights the transformative potential of GQDs in cancer therapy while acknowledging the challenges that researchers must overcome for broader application.

A New Strategy for Ultrasensitive Detection Based on Target microRNA-Triggered Rolling Circle Amplification in the Early Diagnosis of Alzheimer's Disease

There is an urgent need to accurately quantify microRNA (miRNA)-based Alzheimer's disease (AD) biomarkers, which have emerged as promising diagnostic biomarkers. In this study, we present a rapid and universal approach to establishing a target miRNA-triggered rolling circle amplification (RCA) detection strategy, which achieves ultrasensitive detection of several targets, including miR-let7a-5p, miR-34a-5p, miR-206-3p, miR-9-5p, miR-132-3p, miR-146a-5p, and miR-21-5p. Herein, the padlock probe contains three repeated signal strand binding regions and a target miRNA-specific region. The target miRNA-specific region captures miRNA, and then the padlock probe is circularized with the addition of T4 DNA ligase. Subsequently, an RCA reaction is triggered, and RCA products containing multiple signal strand binding regions are generated to trap abundant fluorescein-labeled signal strands. The addition of exonuclease III (Exo III) causes signal strand digestion and leads to RCA product recycling and liberation of fluorescein. Ultimately, graphene oxide (GO) does not absorb the liberated fluorescein because of poor mutual interaction. This method exhibited high specificity, sensitivity, repeatability, and stability toward let-7a, with a detection limit of 19.35 fM and a linear range of 50 fM to 5 nM. Moreover, it showed excellent applicability for recovering miRNAs in normal human serum. Our strategy was applied to detect miRNAs in the plasma of APP/PS1 mice, demonstrating its potential in the diagnosis of miRNA-associated disease and biochemical research.

Anticancer activity of quantum size carbon dots: opportunities and challenges

Research into the anticancer activity of quantum-sized carbon dots (CDs) has emerged as a promising avenue in cancer research. This CDs delves into the opportunities and challenges associated with harnessing the potential of these nanostructures for combating cancer. Quantum-sized carbon dots, owing to their unique physicochemical properties, exhibit distinct advantages as potential therapeutic agents. Opportunities lie in their tunable size, surface functionalization capabilities, and biocompatibility, enabling targeted drug delivery and imaging in cancer cells. However, we include challenges, a comprehensive understanding of the underlying mechanisms, potential toxicity concerns, and the optimization of synthesis methods for enhanced therapeutic efficacy. A succinct summary of the state of the research in this area is given in this review, emphasizing the exciting possibilities and ongoing challenges in utilizing quantum-sized carbon dots as a novel strategy for cancer treatment.

Development of Graphene-Based Materials with the Targeted Action for Cancer Theranostics

The review summarises the prospects in the application of graphene and graphene-based nanomaterials (GBNs) in nanomedicine, including drug delivery, photothermal and photodynamic therapy, and theranostics in cancer treatment. The application of GBNs in various areas of science and medicine is due to the unique properties of graphene allowing the development of novel ground-breaking biomedical applications. The review describes current approaches to the production of new targeting graphene-based biomedical agents for the chemotherapy, photothermal therapy, and photodynamic therapy of tumors. Analysis of publications and FDA databases showed that despite numerous clinical studies of graphene-based materials conducted worldwide, there is a lack of information on the clinical trials on the use of graphene-based conjugates for the targeted drug delivery and diagnostics. The review will be helpful for researchers working in development of carbon nanostructures, material science, medicinal chemistry, and nanobiomedicine.

A review on synthesis, properties, and biomedical applications of graphene quantum dots (GQDs)

A new type of 0-dimensional carbon-based materials called graphene quantum dots (GQDs) is gaining significant attention as a non-toxic and eco-friendly nanomaterial. GQDs are nanomaterials composed of sp2hybridized carbon domains and functional groups, with their lateral size less than 10 nm. The unique and exceptional physical, chemical, and optical properties arising from the combination of graphene structure and quantum confinement effect due to their nano-size make GQDs more intriguing than other nanomaterials. Particularly, the low toxicity and high solubility derived from the carbon core and abundant edge functional groups offer significant advantages for the application of GQDs in the biomedical field. In this review, we summarize various synthetic methods for preparing GQDs and important factors influencing the physical, chemical, optical, and biological properties of GQDs. Furthermore, the recent application of GQDs in the biomedical field, including biosensor, bioimaging, drug delivery, and therapeutics are discussed. Through this, we provide a brief insight on the tremendous potential of GQDs in biomedical applications and the challenges that need to be overcome in the future.

Innovative approaches for cancer treatment: graphene quantum dots for photodynamic and photothermal therapies

Graphene quantum dots (GQDs) hold great promise for photodynamic and photothermal cancer therapies. Their unique properties, such as exceptional photoluminescence, photothermal conversion efficiency, and surface functionalization capabilities, make them attractive candidates for targeted cancer treatment. GQDs have a high photothermal conversion efficiency, meaning they can efficiently convert light energy into heat, leading to localized hyperthermia in tumors. By targeting the tumor site with laser irradiation, GQD-based nanosystems can induce selective cancer cell destruction while sparing healthy tissues. In photodynamic therapy, light-sensitive compounds known as photosensitizers are activated by light of specific wavelengths, generating reactive oxygen species that induce cancer cell death. GQD-based nanosystems can act as excellent photosensitizers due to their ability to absorb light across a broad spectrum; their nanoscale size allows for deeper tissue penetration, enhancing the therapeutic effect. The combination of photothermal and photodynamic therapies using GQDs holds immense potential in cancer treatment. By integrating GQDs into this combination therapy approach, researchers aim to achieve enhanced therapeutic efficacy through synergistic effects. However, biodistribution and biodegradation of GQDs within the body present a significant hurdle to overcome, as ensuring their effective delivery to the tumor site and stability during treatment is crucial for therapeutic efficacy. In addition, achieving precise targeting specificity of GQDs to cancer cells is a challenging task that requires further exploration. Moreover, improving the photothermal conversion efficiency of GQDs, controlling reactive oxygen species generation for photodynamic therapy, and evaluating their long-term biocompatibility are all areas that demand attention. Scalability and cost-effectiveness of GQD synthesis methods, as well as obtaining regulatory approval for clinical applications, are also hurdles that need to be addressed. Further exploration of GQDs in photothermal and photodynamic cancer therapies holds promise for advancements in targeted drug delivery, personalized medicine approaches, and the development of innovative combination therapies. The purpose of this review is to critically examine the current trends and advancements in the application of GQDs in photothermal and photodynamic cancer therapies, highlighting their potential benefits, advantages, and future perspectives as well as addressing the crucial challenges that need to be overcome for their practical application in targeted cancer therapy.

Enzyme-Responsive Modular Peptides Enhance Tumor Penetration of Quantum Dots via Charge Reversal Strategy

Quantum dots (QDs) are colloidal semiconductor nanoparticles acting as fluorescent probes for detection, disease diagnosis, and photothermal and photodynamic therapy. However, their performance in cancer treatment is limited by inadequate tumor accumulation and penetration due to the larger size of nanoparticles compared to small molecules. To address this challenge, charge reversal nanoparticles offer an effective strategy to prolong blood circulation time and achieve enhanced endocytosis and tumor penetration. In this study, we leveraged the overexpressed γ-glutamyl transpeptidase (GGT) in many human tumors and developed a library of modular peptides to serve as water-soluble surface ligands of QDs. We successfully transferred the QDs from the organic phase to the aqueous phase within 5 min. And through systematic tuning of the peptide sequence, we optimized the fluorescent stability of QDs and their charge reversal behavior in response to GGT. The resulting optimal peptide stabilized QDs in aqueous solution with a high fluorescent retention rate of 93% after three months and realized the surface charge reversal of QDs triggered by GGT in vitro. The binding between the peptide and QD surface was investigated by using saturation transfer differential nuclear magnetic resonance (STD NMR). Thanks to its charge reversal ability, the GGT-responsive QDs exhibited enhanced cellular uptake in GGT-expressing cancer cells and deeper penetration in the 3D multicellular spheroids. This enzyme-responsive modular peptide can lead to specific tumor targeting and deeper tumor penetration, holding great promise to enhance the treatment efficacy of QD-based theranostics.

Bioinspired theranostic quantum dots: Paving the road to a new paradigm for cancer diagnosis and therapeutics

Despite extensive research, a complete cure remains lacking for most types of cancer. Nanotechnology-based carriers, such as liposomes, nanoparticles (NPs), dendrimers, nanoemulsions, and other nanocarriers, can target cancer cells, but their in vivo fate is unpredictable. Bioinspired quantum dots (BQDs) offer enhanced aqueous solubility, exceptionally low toxicity, biocompatibility, easy biofunctionalization, and selective cancer targeting. Due to their photoluminescence, high longitudinal relaxation value, photothermal effect upon laser irradiation, generation of singlet oxygen, and production of H2S for gas therapy, BQDs are excellent cancer theranostic agents. In this review, we highlight the theranostic application of, and existing challenges relating to BQDs.

Photothermal antibacterial materials to promote wound healing

Wound healing is a crucial process that restores the integrity and function of the skin and other tissues after injury. However, external factors, such as infection and inflammation, can impair wound healing and cause severe tissue damage. Therefore, developing new drugs or methods to promote wound healing is of great significance. Photothermal therapy (PTT) is a promising technique that uses photothermal agents (PTAs) to convert near-infrared radiation into heat, which can eliminate bacteria and stimulate tissue regeneration. PTT has the advantages of high efficiency, controllability, and low drug resistance. Hence, nanomaterial-based PTT and its related strategies have been widely explored for wound healing applications. However, a comprehensive review of PTT-related strategies for wound healing is still lacking. In this review, we introduce the physiological mechanisms and influencing factors of wound healing, and summarize the types of PTAs commonly used for wound healing. Then, we discuss the strategies for designing nanocomposites for multimodal combination treatment of wounds. Moreover, we review methods to improve the therapeutic efficacy of PTT for wound healing, such as selecting the appropriate wound dressing form, controlling drug release, and changing the infrared irradiation window. Finally, we address the challenges of PTT in wound healing and suggest future directions.

Recent strategies of carbon dot-based nanodrugs for enhanced emerging antitumor modalities

Nanomaterial-based cancer therapy has recently emerged as a new therapeutic modality with the advantages of minimal invasiveness and negligible normal tissue toxicity over traditional cancer treatments. However, the complex microenvironment and self-protective mechanisms of tumors have suppressed the therapeutic effect of emerging antitumor modalities, which seriously hindered the transformation of these modalities to clinical settings. Due to the excellent biocompatibility, unique physicochemical properties and easy surface modification, carbon dots, as promising nanomaterials in the biomedical field, can effectively improve the therapeutic effect of emerging antitumor modalities as multifunctional nanoplatforms. In this review, the mechanism and limitations of emerging therapeutic modalities are described. Further, the recent advances related to carbon dot-based nanoplatforms in overcoming the therapeutic barriers of various emerging therapies are systematically summarized. Finally, the prospects and potential obstacles for the clinical translation of carbon dot-based nanoplatforms in tumor therapy are also discussed. This review is expected to provide a reference for nanomaterial design and its development for the efficacy enhancement of emerging therapeutic modalities.

A Fluorescent Vector of Carbon Dot to Deliver Rab13 and Rab14 Plasmids for Promoting Neurite Outgrowth

The complex processes of neuron differentiation and neuron repair are critical for treating nervous system injuries and neurodegenerative diseases. Neurite outgrowth plays a crucial role in these processes by enabling the formation of connections between neurons and the generation of neuroplasticity to restore the function of the nervous system. In this study, we fabricated functionalized carbon dots (CDs) with distinctive photoluminescence and low cytotoxicity for use as fluorescence imaging probes and nanocarriers to deliver plasmid DNAs to neurons effectively for inducing neurite outgrowth. CDs were prepared through a reflux process in nitric acid solution, and their surface was then modified using polyethylenimine (PEI) to obtain positively charged CDs for increasing the absorption of plasmid DNAs and the efficiency of cell uptake. Experimental results indicated that the fabricated CDs maintained a low cytotoxicity and exhibited a high neuron uptake of up to 97%. An improvement in the plasmid DNA ingestion of neurons resulted in enhanced expression of Rab13-Q67L and Rab14 proteins, which considerably promoted neurite sprouting and elongation. After the fabricated PEI-modified CDs were used to deliver the Rab13-Q67L and Rab14 plasmids, more than 56% of the neurons had a neurite length that was greater than twice the size of their soma. Thus, DNA delivery through functionalized CDs has a high potential for use in gene therapy for neuronal injuries and diseases.

Red blood cells: a potential delivery system

Red blood cells (RBCs) are the most abundant cells in the body, possessing unique biological and physical properties. RBCs have demonstrated outstanding potential as delivery vehicles due to their low immunogenicity, long-circulating cycle, and immune characteristics, exhibiting delivery abilities. There have been several developments in understanding the delivery system of RBCs and their derivatives, and they have been applied in various aspects of biomedicine. This article compared the various physiological and physical characteristics of RBCs, analyzed their potential advantages in delivery systems, and summarized their existing practices in biomedicine.

Theranostic Applications of 2D Graphene-Based Materials for Solid Tumors Treatment

Solid tumors are a leading cause of cancer-related deaths globally, being characterized by rapid tumor growth and local and distant metastases. The failures encountered in cancer treatment are mainly related to the complicated biology of the tumor microenvironment. Nanoparticles-based (NPs) approaches have shown the potential to overcome the limitations caused by the pathophysiological features of solid cancers, enabling the development of multifunctional systems for cancer diagnosis and therapy and allowing effective inhibition of tumor growth. Among the different classes of NPs, 2D graphene-based nanomaterials (GBNs), due to their outstanding chemical and physical properties, easy surface multi-functionalization, near-infrared (NIR) light absorption and tunable biocompatibility, represent ideal nanoplatforms for the development of theranostic tools for the treatment of solid tumors. Here, we reviewed the most recent advances related to the synthesis of nano-systems based on graphene, graphene oxide (GO), reduced graphene oxide (rGO), and graphene quantum dots (GQDs), for the development of theranostic NPs to be used for photoacoustic imaging-guided photothermal-chemotherapy, photothermal (PTT) and photodynamic therapy (PDT), applied to solid tumors destruction. The advantages in using these nano-systems are here discussed for each class of GBNs, taking into consideration the different chemical properties and possibility of multi-functionalization, as well as biodistribution and toxicity aspects that represent a key challenge for their translation into clinical use.

Innovative Metal-Organic Frameworks for Targeted Oral Cancer Therapy: A Review

Metal-organic frameworks (MOFs) have proven to be very effective carriers for drug delivery in various biological applications. In recent years, the development of hybrid nanostructures has made significant progress, including developing an innovative MOF-loaded nanocomposite with a highly porous structure and low toxicity that can be used to fabricate core-shell nanocomposites by combining complementary materials. This review study discusses using MOF materials in cancer treatment, imaging, and antibacterial effects, focusing on oral cancer cells. For patients with oral cancer, we offer a regular program for accurately designing and producing various anticancer and antibacterial agents to achieve maximum effectiveness and the lowest side effects. Also, we want to ensure that the anticancer agent works optimally and has as few side effects as possible before it is tested in vitro and in vivo. It is also essential that new anticancer drugs for cancer treatment are tested for efficacy and safety before they go into further research.

X-ray-responsive prodrugs and polymeric nanocarriers for multimodal cancer therapy

Radiotherapy as one of the most important cancer treatment modalities has been widely used in the therapy of various cancers. The clinically used radiation (e.g. X-ray) for radiotherapy has the advantages of precise spatiotemporal controllability and deep tissue penetration. However, traditional radiotherapy is frequently limited by the high side effects and tumor hypoxia. The combination of radiotherapy and other cancer treatment modalities may overcome the disadvantages of radiotherapy and improve the final therapeutic efficacy. In recent years, X-ray-activable prodrugs and polymeric nanocarriers have been extensively explored to introduce other treatment modalities in the precise position during radiotherapy, which can reduce the side toxicity of the drugs and improve the combination therapeutic efficacy. In this review, we focus on recent advances in X-ray-activable prodrugs and polymeric nanocarriers to boost X-ray-based multimodal synergistic therapy with reduced toxicity. The design strategies of prodrugs and polymeric nanocarriers are highlighted. Finally, challenges and outlooks of X-ray-activable prodrugs and polymeric nanocarriers are discussed.

Recent trends in macromolecule-conjugated hybrid quantum dots for cancer theranostic applications

Quantum dots (QDs) are small nanoparticles with semiconductor properties ranging from 2 to 10 nanometers comprising 10-50 atoms. The single wavelength excitation character of QDs makes it more significant, as it can excite multiple particles in a confined surface simultaneously by narrow emission. QDs are more photostable than traditional organic dyes; however, when injected into tissues, whole animals, or ionic solutions, there is a significant loss of fluorescence. HQD-based probes conjugated with cancer-specific ligands, antibodies, or peptides are used in clinical diagnosis. It is more precise and reliable than standard immunohistochemistry (IHC) at minimal protein expression levels. Advanced clinical studies use photodynamic therapy (PDT) with fluorescence imaging to effectively identify and treat cancer. Recent studies revealed that a combination of unique characteristics of QDs, including their fluorescence capacity and abnormal expression of miRNA in cancer cells, were used for the detection and monitoring progression of cancer. In this review, we have highlighted the unique properties of QDs and the theranostic behavior of various macromolecule-conjugated HQDs leading to cancer treatment.

"Bioinspired" Membrane-Coated Nanosystems in Cancer Theranostics: A Comprehensive Review

Achieving precise cancer theranostics necessitates the rational design of smart nanosystems that ensure high biological safety and minimize non-specific interactions with normal tissues. In this regard, "bioinspired" membrane-coated nanosystems have emerged as a promising approach, providing a versatile platform for the development of next-generation smart nanosystems. This review article presents an in-depth investigation into the potential of these nanosystems for targeted cancer theranostics, encompassing key aspects such as cell membrane sources, isolation techniques, nanoparticle core selection, approaches for coating nanoparticle cores with the cell membrane, and characterization methods. Moreover, this review underscores strategies employed to enhance the multi-functionality of these nanosystems, including lipid insertion, membrane hybridization, metabolic engineering, and genetic modification. Additionally, the applications of these bioinspired nanosystems in cancer diagnosis and therapeutics are discussed, along with the recent advances in this field. Through a comprehensive exploration of membrane-coated nanosystems, this review provides valuable insights into their potential for precise cancer theranostics.

The blood-brain barrier: structure, regulation, and drug delivery

Blood-brain barrier (BBB) is a natural protective membrane that prevents central nervous system (CNS) from toxins and pathogens in blood. However, the presence of BBB complicates the pharmacotherapy for CNS disorders as the most chemical drugs and biopharmaceuticals have been impeded to enter the brain. Insufficient drug delivery into the brain leads to low therapeutic efficacy as well as aggravated side effects due to the accumulation in other organs and tissues. Recent breakthrough in materials science and nanotechnology provides a library of advanced materials with customized structure and property serving as a powerful toolkit for targeted drug delivery. In-depth research in the field of anatomical and pathological study on brain and BBB further facilitates the development of brain-targeted strategies for enhanced BBB crossing. In this review, the physiological structure and different cells contributing to this barrier are summarized. Various emerging strategies for permeability regulation and BBB crossing including passive transcytosis, intranasal administration, ligands conjugation, membrane coating, stimuli-triggered BBB disruption, and other strategies to overcome BBB obstacle are highlighted. Versatile drug delivery systems ranging from organic, inorganic, and biologics-derived materials with their synthesis procedures and unique physio-chemical properties are summarized and analyzed. This review aims to provide an up-to-date and comprehensive guideline for researchers in diverse fields, offering perspectives on further development of brain-targeted drug delivery system.

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 quantum dots: A comprehensive overview

Because of their prospective applications and exceptional features, graphene quantum dots (GQDs) have gotten a lot of recognition as a new class of fluorescent carbon materials. One of the carbon family’s newest superstars is the GQD. Due to its exceptional optoelectrical qualities, it has sparked a lot of curiosity since its debut in 2008. Two of the most important traits are a band gap that is not zero, biocompatibility, and highly changeable characteristics. GQDs have several important characteristics. GQDs have shown potential in a variety of fields, for instance, catalysis, sensing, energy devices, drug delivery, bioimaging, photothermal, and photodynamic therapy. Because this area constantly evolves, it is vital to recognize emerging GQD concerns in the current breakthroughs, primarily since some specific uses and developments in the case of GQDs synthesis have not been thoroughly investigated through previous studies. The current results in the properties, synthesis, as well as benefits of GQDs are discussed in this review study. As per the findings of this research, the GQD’s future investigation is boundless, mainly if the approaching investigation focuses on purifying simplicity and environmentally friendly synthesis, as well as boosting photoluminescence quantum output and manufacturing output of GQDs.

Carbon Dot@MXene Nanozymes with Triple Enzyme-Mimic Activities for Mild NIR-II Photothermal-Amplified Nanocatalytic Therapy

Nanozymes have shown promising potential in disease treatment owing to the advantages of low-cost, facile fabrication, and high stability. However, the highly complex tumor microenvironment (TME) and inherent low catalytic activity severely restrict the clinical applications of nanozymes. Herein, a novel mild hyperthermia-enhanced nanocatalytic therapy platform based on Z-scheme heterojunction nanozymes by depositing N-doped carbon dots (CDs) onto Nb₂ C nanosheets is constructed. CD@Nb₂ C nanozymes not only display outstanding photothermal effects in the safe and efficient NIR-II window but also possess triple enzyme-mimic activities to obtain amplified ROS levels. The triple enzyme-mimic activities and NIR-II photothermal properties of CD nanozymes are enhanced by the construction of Z-scheme heterojunctions owing to the accelerated carrier transfer process. More importantly, the introduction of mild hyperthermia can further improve the peroxidase-mimic and catalase-mimic activities as well as the glGSH depletion abilities of CD@Nb₂ C nanozymes, thereby producing more ROS to efficiently inhibit tumor growth. The combined therapy effect of CD@Nb₂ C nanozymes through mild NIR-II photothermal-enhanced nanocatalytic therapy can achieve complete tumor eradication. This work highlights the efficient tumor therapy potential of heterojunction nanozymes.

Antibacterial and antibiofilm mechanisms of carbon dots: a review

Due to the increasing bacterial resistance to conventional antibiotics, developing safe and effective approaches to combat infections caused by bacteria and biofilms has become an urgent clinical problem. Recently, carbon dots (CDs) have received great attention as a promising alternative to conventional antimicrobial agents due to their excellent antimicrobial efficacy and biocompatibility. Although CDs have been widely used in the field of antibacterial applications, their antibacterial and antibiofilm mechanisms have not been systematically discussed. This review provides a systematic overview on the complicated mechanisms of antibacterial and antibiofilm CDs based on recent development.

Innovative nanotheranostics: Smart nanoparticles based approach to overcome breast cancer stem cells mediated chemo- and radioresistances

The alarming increase in the number of breast cancer patients worldwide and the increasing death rate indicate that the traditional and current medicines are insufficient to fight against it. The onset of chemo- and radioresistances and cancer stem cell-based recurrence make this problem harder, and this hour needs a novel treatment approach. Competent nanoparticle-based accurate drug delivery and cancer nanotheranostics like photothermal therapy, photodynamic therapy, chemodynamic therapy, and sonodynamic therapy can be the key to solving this problem due to their unique characteristics. These innovative formulations can be a better cargo with fewer side effects than the standard chemotherapy and can eliminate the stability problems associated with cancer immunotherapy. The nanotheranostic systems can kill the tumor cells and the resistant breast cancer stem cells by novel mechanisms like local hyperthermia and reactive oxygen species and prevent tumor recurrence. These theranostic systems can also combine with chemotherapy or immunotherapy approaches. These combining approaches can be the future of anticancer therapy, especially to overcome the breast cancer stem cells mediated chemo- and radioresistances. This review paper discusses several novel theranostic systems and smart nanoparticles, their mechanism of action, and their modifications with time. It explains their relevance and market scope in the current era. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Targeting drugs to tumours using cell membrane-coated nanoparticles

Traditional cancer therapeutics, such as chemotherapies, are often limited by their non-specific nature, causing harm to non-malignant tissues. Over the past several decades, nanomedicine researchers have sought to address this challenge by developing nanoscale platforms capable of more precisely delivering drug payloads. Cell membrane-coated nanoparticles (CNPs) are an emerging class of nanocarriers that have demonstrated considerable promise for biomedical applications. Consisting of a synthetic nanoparticulate core camouflaged by a layer of naturally derived cell membranes, CNPs are adept at operating within complex biological environments; depending on the type of cell membrane utilized, the resulting biomimetic nanoformulation is conferred with several properties typically associated with the source cell, including improved biocompatibility, immune evasion and tumour targeting. In comparison with traditional functionalization approaches, cell membrane coating provides a streamlined method for creating multifunctional and multi-antigenic nanoparticles. In this Review, we discuss the history and development of CNPs as well as how these platforms have been used for cancer therapy. The application of CNPs for drug delivery, phototherapy and immunotherapy will be described in detail. Translational efforts are currently under way and further research to address key areas of need will ultimately be required to facilitate the successful clinical adoption of CNPs.

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.

Preparation of Fluorescent Carbon Dots Composites and Their Potential Applications in Biomedicine and Drug Delivery-A Review

Carbon dots (CDs), a new member of carbon nanostructures, rely on surface modification and functionalization for their good fluorescence phosphorescence and excellent physical and chemical properties, including small size (<10 nm), high chemical stability, biocompatibility, non-toxicity, low cost, and easy synthesis. In the field of medical research on cancer (IARC), CDs, a new material with unique optical properties as a photosensitizer, are being applied to heating local apoptosis induction of cancer cells. In addition, imaging tools can also be combined with a drug to form the nanometer complex compound, the imaging guidance for multi-function dosage, so as to improve the efficiency of drug delivery, which also plays a big role in genetic diagnosis. This paper mainly includes three parts: The first part briefly introduces the synthesis and preparation of carbon dots, and summarizes the advantages and disadvantages of different preparation methods; The second part introduces the preparation methods of carbon dot composites. Finally, the application status of carbon dot composites in biomedicine, cancer theranostics, drug delivery, electrochemistry, and photocatalysis is summarized.

Radiopharmacokinetics of Graphene Quantum Dots Nanoparticles In vivo: Comparing the Pharmacokinetics Parameters in Long and Short Periods

BACKGROUND

Nanoparticles (NPs) have gained great importance during the last decades for developing new therapeutics with improved outcomes for biomedical applications due to their nanoscale size, surface properties, loading capacity, controlled drug release, and distribution. Among the carbon-based nanomaterials, one of the most biocompatible forms of graphene is graphene quantum dots (GQDs). GQDs are obtained by converting 2D graphene into zero-dimensional graphene nanosheets. Moreover, very few reports in the literature reported the pharmacokinetic studies proving the safety and effectiveness of GQDs for in vivo applications.

OBJECTIVES

This study evaluated the pharmacokinetics of GQDs radiolabeled with ^99mTc, administered intravenously, in rodents (Wistar rats) in two conditions: short and long periods, to compare and understand the biological behavior.

METHODS

The graphene quantum dots were produced and characterized by RX diffractometry, Raman spectroscopy, and atomic force microscopy. The pharmacokinetic analysis was performed following the radiopharmacokinetics concepts, using radiolabeled graphene quantum dots with technetium 99 metastable (99mTc). The radiolabeling process of the graphene quantum dots with 99mTc was performed by the direct via.

RESULTS

The results indicate that the pharmacokinetic analyses with GQDs over a longer period were more accurate. Following a bicompartmental model, the long-time analysis considers each pharmacokinetic phase of drugs into the body. Furthermore, the data demonstrated that short-time analysis could lead to distortions in pharmacokinetic parameters, leading to misinterpretations.

CONCLUSION

The evaluation of the pharmacokinetics of GQDs over long periods is more meaningful than the evaluation over short periods.

Theoretical Evaluation of Potential Cytotoxicity of Graphene Quantum Dot to Adsorbed DNA

As a zero-dimensional (0D) nanomaterial, graphene quantum dot (GQD) has a unique physical structure and electrochemical properties, which has been widely used in biomedical fields, such as bioimaging, biosensor, drug delivery, etc. Its biological safety and potential cytotoxicity to human and animal cells have become a growing concern in recent years. In particular, the potential DNA structure damage caused by GQD is of great importance but still obscure. In this study, molecular dynamics (MD) simulation was used to investigate the adsorption behavior and the structural changes of single-stranded (ssDNA) and double-stranded DNA (dsDNA) on the surfaces of GQDs with different sizes and oxidation. Our results showed that ssDNA can strongly adsorb and lay flat on the surface of GQDs and graphene oxide quantum dots (GOQDs), whereas dsDNA was preferentially oriented vertically on both surfaces. With the increase of GQDs size, more structural change of adsorbed ssDNA and dsDNA could be found, while the size effect of GOQD on the structure of ssDNA and dsDNA is not significant. These findings may help to improve the understanding of GQD biocompatibility and potential applications of GQD in the biomedical field.

Quantum Dots Mediated Imaging and Phototherapy in Cancer Spheroid Models: State of the Art and Perspectives

Quantum Dots (QDs) are fluorescent nanoparticles known for their exceptional optical properties, i.e., high fluorescence emission, photostability, narrow emission spectrum, and broad excitation wavelength. These properties make QDs an exciting choice for bioimaging applications, notably in cancer imaging. Challenges lie in their ability to specifically label targeted cells. Numerous studies have been carried out with QDs coupled to various ligands like peptides, antibodies, aptamers, etc., to achieve efficient targeting. Most studies were conducted in vitro with two-dimensional cell monolayers (n = 8902) before evolving towards more sophisticated models. Three-dimensional multicellular tumor models better recapitulate in vivo conditions by mimicking cell-to-cell and cell-matrix interactions. To date, only few studies (n = 34) were conducted in 3D in vitro models such as spheroids, whereas these models could better represent QDs behavior in tumors compared to monolayers. Thus, the purpose of this review is to present a state of the art on the studies conducted with Quantum Dots on spheroid models for imaging and phototherapy purposes.

Antiproliferative and Apoptotic Effects of Graphene Oxide @AlFu MOF Based Saponin Natural Product on OSCC Line

The increasing rate of oral squamous cell carcinoma (OSCC) and the undesirable side effects of anticancer agents have enhanced the demand for the development of efficient, detectable, and targeted anticancer systems. Saponins are a diverse family of natural glycosides that have recently been evaluated as an effective compound for the targeted therapy of squamous cell carcinoma. Due to their porous nature and stable structure, metal–organic frameworks (MOFs) are a well-known substance form for various biological applications, such as drug delivery. In this study, we fabricated a novel hybrid, highly porous and low-toxic saponin-loaded nanostructure by modifying graphene oxide (GO)/reduced GO (rGO) with aluminum fumarate (AlFu) as MOF core–shell nanocomposite. The characterization of the nanostructures was investigated by FTIR, TEM, EDX, FESEM, and BET. MTT assay was used to investigate the anticancer activity of these compounds on OSCC and PDL normal dental cells. The effect of the nanocomposites on OSCC was then investigated by studying apoptosis and necrosis using flow cytometry. The GO/rGO was decorated with a saponin–AlFu mixture to further investigate cytotoxicity. The results of the MTT assay showed that PDL cells treated with AlFu–GO–saponin at a concentration of 250 μg/mL had a viability of 74.46 ± 16.02%, while OSCC cells treated with this sample at a similar concentration had a viability of only 38.35 ± 19.9%. The anticancer effect of this nanostructure on OSCC was clearly demonstrated. Moreover, the number of apoptotic cells in the AlFu–GO–saponin and AlFu–rGO–saponin groups was 10.98 ± 2.36%–26.90 ± 3.24% and 15.9 ± 4.08%–29.88 ± 0.41%, respectively, compared with 2.52 ± 0.78%–1.31 ± 0.62% in the untreated group. This significant increase in apoptotic effect observed with AlFu–rGO–saponin was also reflected in the significant anticancer effect of saponin-loaded nanostructures. Therefore, this study suggests that an effective saponin delivery system protocol for the precise design and fabrication of anticancer nanostructures for OSCC therapy should be performed prior to in vivo evaluations.

Recent advances in erythrocyte membrane-camouflaged nanoparticles for the delivery of anti-cancer therapeutics

INTRODUCTION

Red blood cell (or erythrocyte) membrane-camouflaged nanoparticles (RBC-NPs) not only have a superior circulation life and do not induce accelerated blood clearance, but also possess special functions, which offers great potential in cancer therapy.

AREAS COVERED

This review focuses on the recent advances of RBC-NPs for delivering various agents to treat cancers in light of their vital role in improving drug delivery. Meanwhile, the construction and in vivo behavior of RBC-NPs are discussed to provide an in-depth understanding of the basis of RBC-NPs for improved cancer drug delivery.

EXPERT OPINION

Although RBC-NPs are quite prospective in delivering anti-cancer therapeutics, they are still in their infancy stage and many challenges need to be overcome for successful translation into the clinic. The preparation and modification of RBC membranes, the optimization of coating methods, the scale-up production and the quality control of RBC-NPs, and the drug loading and release should be carefully considered in the clinical translation of RBC-NPs for cancer therapy.

Covalent and Noncovalent Loading of Doxorubicin by Folic Acid-Carbon Dot Nanoparticles for Cancer Theranostics

With special properties such as excellent fluoresce features, low toxicity, good biocompatibility, permeability, and easy clearance from the body, carbon dot (CD)-based nanoparticles (NPs) have the potential to deliver drugs and use in vivo diagnostics through molecular imaging. In this work, folic acid-CD (FA-CD) NPs were prepared to deliver doxorubicin (Dox) covalently and noncovalently as cancer theranostics. FA was conjugated to the surface of CDs for targeting cancer cells with overexpressing folate receptors. CDs prepared with various amounts of precursors lead to their associated NPs with different photoluminescence properties and drug release profiles. The loading of Dox and its releasing data depends on the linkage of drug Dox to FA-CD and CD composition. All NPs were characterized by UV-vis, Fourier transform infrared spectroscopy, and dynamic light scattering. The noncovalent FA-CD-Dox NPs were preferred with a simple preparation process, excellent photoluminescence, and in vitro drug release properties. The noncovalent FA-CD-Dox showed the best efficacy against MDA-MB-231 compared to the CD-Dox and covalent FA-CD-Dox.

Novel nano-encapsulated probiotic agents: Encapsulate materials, delivery, and encapsulation systems

Gut microbes are closely associated with most human health. When ingested orally, probiotics can effectively regulate the composition and quantity of human intestinal microorganisms, which is beneficial to human health. However, probiotics will be affected by the harsh environment of the digestive tract during the in vivo transportation process, and ensuring the viability of probiotics is a great challenge. Probiotic encapsulating technology provides an effective solution to this problem. The introduction of extreme temperatures, large probiotic microcapsule sizes and the difficulty in controlling probiotic microcapsule particle sizes mean that traditional microcapsule encapsulation methods have some limitations. From traditional microcapsule technology to the bulk encapsulation of probiotics with nanofibers and nanoparticles to the recent ability to wear nano "armor" for a single probiotic through biofilm, biological membrane and nanocoating. Emerging probiotic nanoagents provides a new conceptual and development direction for the field of probiotic encapsulation. In this review, we presented the characteristics of encapsulated probiotic carrier materials and digestive tract transport systems, we focused on the encapsulation systems of probiotic nanoagents, we analyzed the shortcomings and advantages of the current agent encapsulation systems, and we stated the developmental direction and challenges for these agents for the future.

Graphene quantum dots: A review on the effect of synthesis parameters and theranostic applications

The rising demand for early-stage diagnosis of diseases such as cancer, diabetes, neurodegenerative can be met with the development of materials offering high sensitivity and specificity. Graphene quantum dots (GQDs) have been investigated extensively for theranostic applications owing to their superior photostability and high aqueous dispersibility. These are attractive for a range of biomedical applications as their physicochemical and optoelectronic properties can be tuned precisely. However, many aspects of these properties remain to be explored. In the present review, we have discussed the effect of synthetic parameters upon their physicochemical characteristics relevant to bioimaging. We have highlighted the effect of particle properties upon sensing of biological molecules through 'turn-on' and 'turn-off' fluorescence and generation of electrochemical signals. After describing the effect of surface chemistry and solution pH on optical properties, an inclusive view on application of GQDs in drug delivery and radiation therapy has been given. Finally, a brief overview on their application in gene therapy has also been included.

Spectroscopic investigation on the binding interactions between graphene quantum dots and carbonic anhydrase

As a new member of the nanomaterials family, ultrasmall graphene quantum dots (GQDs) have shown broad application prospects in the field of biomedicine, but the analysis of their biological effects at the molecular level is yet limited. Herein, carbonic anhydrase (CA) was selected as a model protein to assess the interactions between GQDs and biomacromolecules. A range of spectroscopic techniques were employed to systematically investigate the binding interactions between GQDs and CA and the catalytic function of CA in the presence of GQDs was evaluated. Experimental results showed that GQDs could quench the intrinsic fluorescence of CA and the concentration dependent quenching efficiency exhibited an obvious deviation from the linear plot, indicating a static binding mode. Further investigation suggested that van der Waal interactions and hydrogen bonding were the main driving forces. Additionally, circular dichroism measurement showed that the binding of GQDs induced slight conformational changes of CA. The catalytic capability assessment proved that these binding interactions resulted in the reduction of the biological functions of CA. This comprehensive study provided important insight into the interaction of GQDs with biomacromolecules, which would be crucial for the further applications of GQDs and other nanomaterials in the biomedical field.

Synthesis, Applications, and Prospects of Graphene Quantum Dots: A Comprehensive Review

Graphene quantum dot (GQD) is one of the youngest superstars of the carbon family. Since its emergence in 2008, GQD has attracted a great deal of attention due to its unique optoelectrical properties. Non-zero bandgap, the ability to accommodate functional groups and dopants, excellent dispersibility, highly tunable properties, and biocompatibility are among the most important characteristics of GQDs. To date, GQDs have displayed significant momentum in numerous fields such as energy devices, catalysis, sensing, photodynamic and photothermal therapy, drug delivery, and bioimaging. As this field is rapidly evolving, there is a strong need to identify the emerging challenges of GQDs in recent advances, mainly because some novel applications and numerous innovations on the ease of synthesis of GQDs are not systematically reviewed in earlier studies. This feature article provides a comparative and balanced discussion of recent advances in synthesis, properties, and applications of GQDs. Besides, current challenges and future prospects of these emerging carbon-based nanomaterials are also highlighted. The outlook provided in this review points out that the future of GQD research is boundless, particularly if upcoming studies focus on the ease of purification and eco-friendly synthesis along with improving the photoluminescence quantum yield and production yield of GQDs.

Accurate construction of cell membrane biomimetic graphene nanodecoys via purposeful surface engineering to improve screening efficiency of active components of traditional Chinese medicine

Biomimetic nanoengineering presents great potential in biomedical research by integrating cell membrane (CM) with functional nanoparticles. However, preparation of CM biomimetic nanomaterials for custom applications that can avoid the aggregation of nanocarriers while maintaining the biological activity of CM remains a challenge. Herein, a high-performance CM biomimetic graphene nanodecoy was fabricated via purposeful surface engineering, where polyethylene glycol (PEG) was used to modifying magnetic graphene oxide (MGO) to improve its stability in physiological solution, so as to improve the screening efficiency to active components of traditional Chinese medicine (TCM). With this strategy, the constructed PEGylated MGO (PMGO) could keep stable at least 10 days, thus improving the CM coating efficiency. Meanwhile, by taking advantage of the inherent ability of HeLa cell membrane (HM) to interact with specific ligands, HM-camouflaged PMGO showed satisfied adsorption capacity (116.2 mg/g) and selectivity. Finally, three potential active components, byakangelicol, imperatorin, and isoimperatorin, were screened from Angelica dahurica, whose potential antiproliferative activity were further validated by pharmacological studies. These results demonstrated that the purposeful surface engineering is a promising strategy for the design of efficient CM biomimetic nanomaterials, which will promote the development of active components screening in TCM.

Emerging strategies in developing multifunctional nanomaterials for cancer nanotheranostics

Cancer involves a collection of diseases with a common trait - dysregulation in cell proliferation. At present, traditional therapeutic strategies against cancer have limitations in tackling various tumors in clinical settings. These include chemotherapeutic resistance and the inability to overcome intrinsic physiological barriers to drug delivery. Nanomaterials have presented promising strategies for tumor treatment in recent years. Nanotheranostics combine therapeutic and bioimaging functionalities at the single nanoparticle level and have experienced tremendous growth over the past few years. This review highlights recent developments of advanced nanomaterials and nanotheranostics in three main directions: stimulus-responsive nanomaterials, nanocarriers targeting the tumor microenvironment, and emerging nanomaterials that integrate with phototherapies and immunotherapies. We also discuss the cytotoxicity and outlook of next-generation nanomaterials towards clinical implementation.

Graphene quantum dots (GQDs) nanoarchitectonics for theranostic application in lung cancer

Lung cancer (LC) is heading up as a substantial cause of mortality worldwide. Despite enormous progress in cancer management, LC remains a crucial problem for oncologists due to the lack of early diagnosis and precise treatment. In this context, numerous early diagnosis and treatment approaches for LC at the cellular level have been developed using advanced nanomaterials in the last decades. Amongst this, graphene quantum dots (GQDs) as a novel fluorescent material overwhelmed the horizons of materials science and biomedical fields due to their multifunctional attributes. Considering the complex nature of LC, emerging diagnostic and therapeutic (Theranostics) strategies using GQDs proved to be an effective way for the current practice in LC. In this line, we have abridged various approaches used in the LC theranostics using GQDs and its surface-engineered motif. The admirable photophysical attributes of GQDs realised in photolytic therapy (PLT), hyperthermia therapy (HTT), and drug delivery have been discussed. Furthermore, we have engrossed the impasse and its effects on the use of GQDs in cancer treatments from cellular level (in vivo-in vitro) to clinical. Inclusively, this review will be an embodiment for the scientific fraternity to design and magnify their view for the theranostic application of GQDs in LC treatment.

State of the Art and Perspectives on the Biofunctionalization of Fluorescent Metal Nanoclusters and Carbon Quantum Dots for Targeted Imaging and Drug Delivery

The interface of nanobio science and cancer nanomedicine is one of the most important current frontiers in research, being full of opportunities and challenges. Ultrasmall fluorescent metal nanoclusters (MNCs) and carbon quantum dots (CQDs) have emerged as promising fluorescent nanomaterials due to their unique physicochemical and optical properties, facile surface functionalization, good photostability, biocompatibility, and aqueous dispersity. These characteristics make them advantageous over conventional fluorophores such as organic dye molecules and semiconductor quantum dots (QDs) for the detection, diagnosis, and treatment of various diseases including cancer. Recently, researchers have focused on the biofunctionalization strategy of the MNCs and CQDs which can tailor their physicochemical and biological properties and, in turn, can empower these biofunctionalized nanoprobes for diverse applications including imaging, drug delivery, theranostics, and other biomedical applications. In this invited feature article, we first discuss some fundamental structural and physicochemical characteristics of the fluorescent biocompatible quantum-sized nanomaterials which have some outstanding features for the development of multiplexed imaging probes, delivery vehicles, and cancer nanomedicine. We then demonstrate the diverse surface engineering of these fluorescent nanomaterials with reactive target specific functional groups which can help to construct multifunctional nanoprobes with improved targeting capabilities having minimal toxicity. The promising future of the biofunctionalized fluorescent quantum-sized nanomaterials in the field of bioanalytical and biomedical research is elaborately demonstrated, showing selected recent works with relevant applications. This invited feature article finally ends with a short discussion of the current challenges and future prospects of the development of these bioconjugated/biofunctionalized nanomaterials to provide insight into this burgeoning field of MNC- and CQD-based diagnostics and therapeutic applications.

Recent progress in targeted delivery vectors based on biomimetic nanoparticles

Over the past decades, great interest has been given to biomimetic nanoparticles (BNPs) since the rise of targeted drug delivery systems and biomimetic nanotechnology. Biological vectors including cell membranes, extracellular vesicles (EVs), and viruses are considered promising candidates for targeted delivery owing to their biocompatibility and biodegradability. BNPs, the integration of biological vectors and functional agents, are anticipated to load cargos or camouflage synthetic nanoparticles to achieve targeted delivery. Despite their excellent intrinsic properties, natural vectors are deliberately modified to endow multiple functions such as good permeability, improved loading capability, and high specificity. Through structural modification and transformation of the vectors, they are pervasively utilized as more effective vehicles that can deliver contrast agents, chemotherapy drugs, nucleic acids, and genes to target sites for refractory disease therapy. This review summarizes recent advances in targeted delivery vectors based on cell membranes, EVs, and viruses, highlighting the potential applications of BNPs in the fields of biomedical imaging and therapy industry, as well as discussing the possibility of clinical translation and exploitation trend of these BNPs.