Multifunctional Carbon Nanodots: Enhanced Near‐Infrared Photosensitizing, Photothermal Activity, and Body Clearance

Advances in photoactivated carbon-based nanostructured materials for targeted cancer therapy

In this review, we explore key innovations in photoactivated therapeutic programming of carbon-based nanomaterials (CBNs), focusing on their diverse nanostructural configurations and their exceptional photothermal, photochemical, and photoacoustic properties. These attributes position CBNs as remarkable phototherapeutic agents, capable of addressing critical challenges in targeted cancer therapy through their precision, multifunctionality, and adaptability to specific therapeutic modalities. We will explore their diverse derivatives, and the role of chemical augmentation and site-specific surface functionalisation, which are pivotal in optimising the targeting and efficacy of phototherapeutic interventions. The biological and physical relevance of this ever-growing library of nanomaterials in targeted phototherapy will be thoroughly explored. Dynamic photo-triggering of the underlying molecular mechanisms of action e.g., energy conversion modalities lie at the heart of these therapeutic innovations. We will further discuss the tunability and programming of these carriers and structure-function alterations at specific therapeutic wavelengths. The application space of phototherapies is thoroughly mapped exploring the three primary approaches of photothermal therapy, photodynamic therapy and photochemical internalisation as well as emerging techniques and promising multimodal approaches that combine two or more of these processes. The specificity of the target tissue site and the approach under study forms another critical focus area of this review, with an emphasis on three types of cancer-breast cancer, lung cancer, and gliomas-that have demonstrated some of the most promising outcomes from photomedicine. We also provide a perspective on in vitro and in vivo validation and preclinical testing of CBNs for phototherapeutic applications. Finally, we reflect on the potential of CBNs to revolutionise targeted cancer therapy through data-driven materials design and integration with computational tools for biophysical performance optimisation. The exciting integration of machine learning into nanoparticle research and phototherapy has potential to fundamentally transform the landscape of nanomedicine. These techniques ranging from supervised learning algorithms such as random forests and support vector machines to more advanced neural networks and deep learning, can enable unprecedented precision in predicting, optimising, and tailoring the properties of nanoparticles for targeted applications. The transformative impact of photoactivated CBNs in advancing cancer treatment, paves the way for their clinical application and widespread adoption in personalised photomedicine. We conclude with a section on the current challenges facing the reproducibility, manufacturing throughput, and biocompatibility of these nanostructured materials including their long-term effects in trials and degradation profiles in biological systems as evaluated in vitro and in vivo.

Spatiotemporally Controlled Co-Treatment of Lung Cancer and Pulmonary Immune-Related Adverse Events by Inhalable Albumin-Chaperoned Ultrathin MnO2 Nanosheets

Cancer immunotherapy is often associated with immune-related adverse events (irAE), particularly in the lungs, which can lead to treatment discontinuation and negatively impact patient outcomes. In this study, we explore a spatiotemporally controlled cotreatment of lung cancer and pulmonary irAE using inhalable albumin-chaperoned ultrathin MnO2 nanosheets (MnO2@BSA). The MnO2@BSA exhibits efficient reactive oxygen species scavenging and NIR-II photothermal properties. The inhalation route enhances MnO2@BSA accumulation in the lungs and tumor tissue, offering localized treatment with reduced systemic toxicity. We demonstrate that ultrathin MnO2@BSA nanosheets can inhibit the formation of neutrophil extracellular traps (NETs) by reducing reactive oxygen species (ROS) in neutrophils, thereby alleviating inflammation associated with irAE. In animal models, inhaled MnO2@BSA reduced lung injury and inflammatory cell infiltration, while also decreasing pro-inflammatory cytokine levels, such as TNF-α, IL-1β, and IL-6. Simultaneously, MnO2@BSA displays strong photothermal properties under 1064 nm laser irradiation, effectively ablating tumors. This photothermal therapy also induces immunogenic cell death (ICD), promoting the reuse of activated CD8+ T cells to enhance antitumor immunity. These dual effects─tumor destruction and irAE mitigation─highlight MnO2@BSA's potential as a therapeutic platform for addressing the challenges of immunotherapy in lung cancer. We anticipate that this work could contribute to the development of inhalable metal-based nanomedicine for clinical transformation in tumor immunotherapy.

Carbon Nanodots-Based Polymer Nanocomposite: A Potential Drug Delivery Armament of Phytopharmaceuticals

Carbon nanodots (CNDs) have garnered significant attention as viable drug delivery vehicles in recent years, especially in the field of phytomedicine. Although there is much promise for therapeutic applications with phytomedicine, its effectiveness is frequently restricted by its low solubility, stability, and bioavailability. This paper offers a thorough synopsis of the developing field of phytomedicine drug delivery based on CND. It explores CND synthesis processes, surface functionalization strategies, and structural and optical characteristics. Additionally, the advantages and difficulties of phytomedicine are examined, with a focus on the contribution of drug delivery methods to the increased effectiveness of phytomedicine. The applications of CNDs in drug delivery are also included in the review, along with the mechanisms that underlie their improved drug delivery capabilities. Additionally, it looks at controlled-release methods, stability augmentation, and phytomedicine-loading tactics onto CNDs. The potential of polymeric carbon nanodots in drug delivery is also covered, along with difficulties and prospective directions going forward, such as resolving toxicity and biocompatibility issues. In summary, the present review highlights the encouraging contribution of CNDs to the field of drug delivery, specifically in enhancing the potential of phytomedicine for therapeutic purposes.

Recent Progress on Second Near-Infrared Emitting Carbon Dots in Biomedicine

Second near-infrared (NIR-II) carbon dots, with absorption or emission between 1000 and 1700 nm, are gaining increasing attention in the biomaterial field due to their distinctive properties, which include straightforward preparation processes, stable photophysical characteristics, excellent biocompatibility, and low cost. As a result, there is a growing focus on the controlled synthesis and modulation of the photochemical and photophysical properties of NIR-II carbon dots, with the aim to further expand their biomedical applications, a current research hotspot. This account aims to provide a comprehensive overview of the recent advancements in NIR-II carbon dots within the biomedical field. The review will cover the following topics: (i) the design, synthesis, and purification of NIR-II carbon dots, (ii) the surface modification strategies, and (iii) the biomedical applications, particularly in the domain of cancer theranostics. Additionally, this account addresses the challenges encountered by NIR-II carbon dots and will outline future directions in the realm of cancer theranostics. By exploring carbon-based NIR-II biomaterials, we can anticipate that this contribution will garner increased attention and contribute to the development of next-generation advanced functional carbon dots, thereby offering enhanced tools and strategies in the biomedical field.

Carbon nanodots constructed by ginsenosides and their high inhibitory effect on neuroblastoma

BACKGROUND

Neuroblastoma is one of the common extracranial tumors in children (infants to 2 years), accounting for 8 ~ 10% of all malignant tumors. Few special drugs have been used for clinical treatment currently.

RESULTS

In this work, herbal extract ginsenosides were used to synthesize fluorescent ginsenosides carbon nanodots via a one-step hydrothermal method. At a low cocultured concentration (50 µg·mL^- 1) of ginsenosides carbon nanodots, the inhibition rate and apoptosis rate of SH-SY5Y cells reached ~ 45.00% and ~ 59.66%. The in vivo experiments showed tumor volume and weight of mice in ginsenosides carbon nanodots group were ~ 49.81% and ~ 34.14% to mice in model group. Since ginsenosides were used as sole reactant, ginsenosides carbon nanodots showed low toxicity and good animal response.

CONCLUSION

Low-cost ginsenosides carbon nanodots as a new type of nanomedicine with good curative effect and little toxicity show application prospects for clinical treatment of neuroblastoma. It is proposed a new design for nanomedicine based on bioactive carbon nanodots, which used natural bioactive molecules as sole source.

Mechanisms of Radical Formation on Chemically Modified Graphene Oxide under Near Infrared Irradiation

In this work, the mechanisms of radical generation on different functionalized graphene oxide (GO) conjugates under near-infrared (NIR) light irradiation are investigated. The GO conjugates are designed to understand how chemical functionalization can influence the generation of radicals. Both pristine and functionalized GO are irradiated by a NIR laser, and the production of different reactive oxygen species (ROS) is investigated using fluorimetry and electron paramagnetic resonance to describe the type of radicals present on the surface of GO. The mechanism of ROS formation involves a charge transfer from the material to the oxygen present in the media, via the production of superoxide and singlet oxygen. Cytotoxicity and effects of ROS generation are then evaluated using breast cancer cells, evidencing a concentration dependent cell death associated to the heat and ROS. The study provides new hints to understand the photogeneration of radicals on the surface of GO upon near infrared irradiation, as well as, to assess the impact on these radicals in the context of a combined drug delivery system and phototherapeutic approach. These discoveries open the way for a better control of phototherapy-based treatments employing graphene-based materials.

Recent Advances of Photoactive Near-Infrared Carbon Dots in Cancer Photodynamic Therapy

Photodynamic therapy (PDT) is a treatment that employs exogenously produced reactive oxygen species (ROS) to kill cancer cells. ROS are generated from the interaction of excited-state photosensitizers (PSs) or photosensitizing agents with molecular oxygen. Novel PSs with high ROS generation efficiency is essential and highly required for cancer photodynamic therapy. Carbon dots (CDs), the rising star of carbon-based nanomaterial family, have shown great potential in cancer PDT benefiting from their excellent photoactivity, luminescence properties, low price, and biocompatibility. In recent years, photoactive near-infrared CDs (PNCDs) have attracted increasing interest in this field due to their deep therapeutic tissue penetration, superior imaging performance, excellent photoactivity, and photostability. In this review, we review recent progress in the designs, fabrication, and applications of PNCDs in cancer PDT. We also provide insights of future directions in accelerating the clinical progress of PNCDs.

Carbon dots conjugated to SN38 for improved colorectal anticancer therapy

Irinotecan (CTP-11) is one of the standard therapies for colorectal cancer (CRC). CTP-11 is enzymatically converted to the hydrophobic 7-ethyl-10-hydroxycamptothecin (SN38), a one hundred-fold more active metabolite. Conjugation of hydrophobic anticancer drugs to nanomaterials is a strategy to improve their solubility, efficacy, and selectivity. Carbon dots (CDs) have garnered interest for their small sizes (<10 ​nm), low toxicity, high water solubility, and bright fluorescence. This paper describes the use of CDs to improve drug vehiculation, stability, and chemotherapeutic efficiency of SN38 through a direct intracellular uptake in CRC. The covalent conjugation of SN38 to CDs via a carbamate bond provides a CD-SN38 hybrid material for slow, sustained, and pH-responsive drug release. CD-SN38 successfully penetrates the CRC cells with a release in the nucleus affecting first the cell cycle and then the cytoskeleton. Moreover, CD-SN38 leads to a deregulation of the extracellular matrix (ECM), one of the major components of the cancer niche considered a possible target therapy for reducing the cancer progression. This work shows the combined therapeutic and imaging potential of CD-based hybrid materials for the treatment of CRC. Future efforts for targeted therapy of chronic diseases characterized by altered ECM deposition, such as chronic kidney disease and chronic allograft nephropathy in kidney transplant patients are envisaged.