Biomass-derived carbon dots with pharmacological activity for biomedicine: Recent advances and future perspectives

From molecular mechanisms to clinical translation: Silk fibroin-based biomaterials for next-generation wound healing

Silk fibroin (SF) is a natural polymeric material that has attracted intense research attention in the field of wound healing due to its exceptional mechanical properties, tunable biodegradability, and multifunctional bioactivity. This review systematically summarizes the preparation strategies, functional modifications, and multidimensional application mechanisms of SF and its composite materials in wound healing. The innovative applications of SF in intelligent dressing design, immunometabolic regulation, controlled drug release, stem-cell function modulation, and bioelectrical-activity-mediated microenvironment remodeling is further explored, while analyzing the therapeutic efficacy and cost-effectiveness of SF through clinical translation cases. Distinct from previous reviews, this work not only integrates the latest advances in SF molecular mechanisms and material design but also emphasizes its potential in precision medicine, such as the development of genetically engineered SF for customized immunoregulatory networks. Finally, the article highlights the current challenges in the development of SF materials, including mechanical stability, degradation controllability, and standardization of large-scale production, and envisions future research directions driven by 3D bioprinting and synthetic biology technologies. This review provides a theoretical foundation and technical reference information for the development of efficient, multifunctional, and clinically translatable SF-based materials for application in wound healing.

Carbon dots from purple sweet potato as a promising anti-inflammatory biomaterial for alleviating the LPS-induced inflammation in macrophages

This study synthesizes carbon dots derived from crude extracts of purple sweet potato (CPP-CDs) and evaluates its anti-inflammatory effects in a lipopolysaccharide (LPS) -induced acute inflammation model. Characterization revealed that CPP-CDs possess a uniform spherical structure and excellent photoluminescent properties. In vitro, CPP-CDs significantly inhibited the expression of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α), reduced the accumulation of reactive oxygen species (ROS), suppressed pyroptosis, and facilitated the polarization of macrophages from the M1 phenotype to the M2 phenotype. In vivo, CPP-CDs significantly improved the survival rates of LPS-treated mice, mitigated tissue damage, and suppressed the levels of pro-inflammatory cytokines. Mechanistic studies indicated that CPP-CDs exert anti-inflammatory effects through the inhibition of the TLR4/NF-κB signaling pathway and the modulation of the NLRP3 inflammasome. Additionally, CPP-CDs exhibited excellent biocompatibility, with no significant toxicity observed in mice. This study provides strong evidence supporting the application of CPP-CDs as a novel anti-inflammatory material, highlighting their potential for acute inflammation treatment and expanding the possibilities for the development of carbon-dot-based anti-inflammatory therapies.

Lyophilized tumour cell-loaded 10B-doped carbon dots for simultaneous boron neutron capture therapy and enhancement of antitumor immunity of prostate cancer

10B agents are critical components in the application of boron neutron capture therapy (BNCT) for tumor treatment. The development of a multi-functional 10B agent plays an important role in the application of BNCT. This study presents a pioneering lyophilized-tumour-cell-based approach for the enhanced accumulation of 10B-doped carbon dots (10B-CDs) within tumour tissue, irradiating thermal neutrons to treat prostate cancer. In this platform, lyophilized RM-1 cells function as both tumor cell antigens and delivery vehicles for 10B-CDs. This design facilitates the co-delivery of tumor antigens and 10B, thereby changing the immune status from "cold" to "hot" and prolonging the retention time of the 10B-CDs in vivo. Prostate cancer cells killed by BNCT mediated by this 10B agent not only damage the DNA, but ferroptosis is also an underlying mechanism. This powerful binary co-delivery system offers a novel strategy for combining BNCT with immunotherapy in the treatment of prostate cancer, providing a promising approach for BNCT-based combination immunotherapy.

Drug Repurposing: Unique Carbon Dot Antibacterial Films for Fruit Postharvest Preservation

Fruit spoilage caused by oxidation and microbial infection exacerbates resource wastage. Although starch films including chitosan possessed admirable biocompatibility owing to great biodegradability compared with conventional plastics, deficient antibacterial and antioxidant capacity restricted food shelf life. Herein, an environmentally friendly antibacterial film (CS/G-CDs) was constructed by carbon dots derived from Cirsii Herba (CDs), which was formed through high affinity resulting from hydrogen bonding between chitosan molecules and hydroxyl originating from CDs. The prepared CDs presented homogeneous and monodisperse spherical structures with an ultrasmall size, providing favorable conditions for uniform film formation. Encouragingly, the antioxidant capacity of CS/G-CDs increased 5.00-fold, followed by an antibacterial rate of up to 97.0%. Dramatically, CS/G-CDs revealed glorious UV shielding efficacy (99.9% for UVB and 98.2% for UVA), and its preservation time for blueberries was remarkably extended 8 days longer than that of the chitosan film. Overall, Chinese herb-derived antibacterial films exhibited magnified antibacterial/antioxidant properties and great biocompatibility, which provided a promising strategy for sustainable development of packaging materials.

Lignin-derived carbon dots with molten salt confinement for ultra-stable room-temperature phosphorescence

In response to the critical challenges of high toxicity, complex synthesis, and poor environmental stability in conventional room-temperature phosphorescent materials, this study presents a sustainable biomass-derived strategy through the development of lignin-based carbon dot/inorganic salt composites (CDSLX-T). By employing a one-step molten salt approach, we construct a hierarchical architecture featuring lignin-derived sp2-hybridized carbon cores and a rigid crystalline shell comprising multi-component inorganic salts (MgO/Mg3(PO4)2/KCl/KNO3). The inherent conjugated moieties of lignin facilitate efficient intersystem crossing, while nitrogen doping optimizes (n, π*) electronic configurations to enhance spin-orbit coupling effects. In situ characterization elucidates the synergistic mechanism of high-temperature-induced carbon core aromatization and salt matrix crystallization. A dual confinement strategy-combining covalent bonding (C-K/C-Cl/C-Mg) and spatial restriction-effectively suppresses carbon dot vibrations and non-radiative triplet exciton transitions, enabling stable phosphorescence emission in aqueous environments. Leveraging time-resolved luminescence characteristics with tunable lifetimes, the material demonstrates unique potential in fingerprint visualization and multilevel information encryption. This work establishes an eco-friendly synthetic paradigm for high-performance bio-based optical materials, bridging sustainable chemistry with advanced photonic applications.

Silkworm Cocoon-Derived Carbon Dots for Post-Trauma Hemostasis and Tissue Repair

Background: Traumatic hemorrhage management is challenging due to the need to control severe bleeding and support tissue repair. An ideal material would possess both hemostatic and wound-healing properties. Methods: Silkworm cocoon-derived carbon dots (SC-CDs) were synthesized via a hydrothermal method. After physical and chemical characterization using techniques such as HR-TEM and XPS, their hemostatic efficacy was assessed in rat liver injury, tail transection, and mouse coagulation disorder models. Moreover, the effects of the SC-CDs on platelet aggregation and activation were evaluated. The potential of the SC-CDs to promote wound healing was investigated through cell scratch assays and a mouse full-thickness skin defect model. Results: The SC-CDs showed a high quantum yield (12.9% ± 0.42%), with low hemolytic activity and cytotoxicity. In the hemostasis models, the SC-CDs significantly reduced the bleeding time and volume. In the rat liver injury model, the bleeding time was shortened from 152.67 ± 4.16 s (Control) to 55.33 ± 9.50 s (p < 0.05). In the rat tail transection model, the bleeding volume was reduced from 1.71 ± 0.16 g (Control) to 0.4 ± 0.11 g (p < 0.05). In the mouse coagulation disorder model, an 8 mg/kg dose reduced the bleeding volume to 11.80% ± 0.39% of that of the Control (p < 0.05). Mechanistic studies suggested enhanced platelet activation and aggregation. In the wound healing experiments, the SC-CDs reduced the wound area (88.53 ± 11.78 mm2 (Control) vs. 70.07 ± 6.71 mm2 (SC-CDs), p < 0.05) and promoted fibroblast migration (24 h scratch width: 372.34 ± 9.06 μm (Control) vs. 259.49 ± 36.75 μm (SC-CDs), p < 0.05). Conclusions: SC-CDs show promise for hemorrhage management and tissue regeneration, with potential applications in cases of internal bleeding or coagulation disorders.

Therapeutic potential of naturally derived carbon dots in sepsis-associated acute kidney injury

BACKGROUND

Sepsis is a life-threatening infectious disease characterized by an uncontrolled inflammatory response and consequent multi-organ dysfunction. The kidneys, as primary excretory organs with high blood flow, are particularly susceptible to damage during sepsis. Nonetheless, the existing treatment options for sepsis-associated acute kidney injury (SA-AKI) are still restricted. Nanomedicine, especially carbon dots (CDs), has attracted considerable interest lately for outstanding biomedical characteristics.

METHODS

To avoid the generation of toxic effects, the natural CDs derived from Ziziphi Spinosae Semen (Z-CDs) were synthesized employing a hydrothermal method. The free radical scavenging capabilities of Z-CDs were evaluated by utilizing ABTS assay, NBT method, and Fenton reaction. A lipopolysaccharide (LPS)-stimulated RAW 264.7 cell model was used to explore the therapeutic potential of Z-CDs on cellular oxidative stress and inflammation. The CuSO4-induced zebrafish inflammation model and LPS-exposed SA-AKI mouse model were employed to assess the therapeutic efficacy of Z-CDs in vivo.

RESULTS

The synthesized Z-CDs exhibited distinctive unsaturated surface functional groups, which confer exceptional biocompatibility and the ability to scavenge free radicals. Moreover, Z-CDs were particularly effective in eliminating excess reactive oxygen species (ROS) in cells, thus protecting mitochondrial function from oxidative damage. Notably, Z-CDs have demonstrated significant therapeutic benefits in protecting kidney tissue in SA-AKI mouse model with minimizing side effects. In mechanism, Z-CDs effectively reduced ROS production, thereby alleviating inflammatory responses in macrophages through the suppression of the NF-κB pathway.

CONCLUSIONS

This study developed a multifunctional nanomedicine derived from traditional medicinal herb, providing a promising pathway for the advancement of innovative drug therapies to treat SA-AKI.

Exploring Carbon Dots for Biological Lasers

Biological lasers, representing innovative miniaturized laser technology, hold immense potential in the fields of biological imaging, detection, sensing, and medical treatment. However, the reported gain media for biological lasers encounter several challenges complex preparation procedures, high cost, toxicity concerns, limited biocompatibility, and stability issues along with poor processability and tunability. These drawbacks have impeded the sustainable development of biological lasers. Carbon dots (CDs), as a novel solution-processable gain materials characterized by facile preparation, low cost, low toxicity, excellent biocompatibility, high stability, easy modification, and luminescence tuning capabilities along with outstanding luminescence performance. Consequently, they find extensive applications in diverse fields such as biology, sensing, photoelectricity, and lasers. Henceforth, they are particularly suitable for constructing biological lasers. This paper provides a comprehensive review on the classification and application of existing biological lasers while emphasizing the advantages of CDs compared to other gain media. Furthermore, it presents the latest progress made by utilizing CDs as gain media and forecasts both promising prospects and potential challenges for biological lasers based on CDs. This study aims to enhance understanding of CD lasers and foster advancements in the field of biological lasers.

Eco-Friendly Synthesized Carbon Dots from Chinese Herbal Medicine: A Review

Chinese herbal medicines and their extracts will produce nano-components of charcoal drugs after high-temperature carbonization, and the process is similar to that of carbon dots (CDs). Chinese herbal medicine-derived CDs (CHM-CDs) are a new carbon-based nanomaterial with a particle size of less than 10 nm discovered in charcoal drugs in recent years. CHM-CDs possess a range of beneficial traits, such as minimal toxicity, strong water solubility, superior biocompatibility, and remarkable photoluminescence capabilities. Additionally, they exhibit multifaceted pharmacological activity in the absence of drug loading. Over the past half-decade, numerous publications have presented evidence suggesting that CHM-CDs exhibit a wide array of pharmacological effects. These primarily encompass hemostatic capabilities, neuroprotection, anti-infective, antitumor, immunomodulatory effects and hypoglycemic activity. Notably, they have been associated with circulatory system, digestive system, nervous system, immune system, endocrine system, urinary system and skeletal system. This article systematically reviews the modern pharmacological effects and potential mechanisms of CHM-CDs, offering insights into current challenges and proposing directions for future advancements. As such, it serves as a vital reference for the clinical application of CHM-CDs.

Adjusting TADF and Phosphorescence for Tailored Dynamic Time-Dependent Afterglow Colored Carbon Dots spanning Full Visible Region

Time-dependent afterglow colored (TDAC) behavior differs from static afterglow by involving wavelength changes, enabling low-cost, high-level encryption and anti-counterfeiting. However, the existing carbon dot (CD)-based TDAC materials lack a clear mechanistic explanation and controllable wavelength changes, significantly hindering the progress of practical applications in this field. In this study, we synthesized CDs composites with customizable tunable TDAC wavelengths across the visible region. Furthermore, we elucidated the underlying mechanism of TDAC that exhibits sequential weakening and relative strengthening of long- and short-wavelength afterglow centers. This phenomenon arises due to strong emission with a short lifetime originating from long-wavelength thermally activated delayed fluorescence (TADF), along with weak emission having a longer lifetime originating from short-wavelength phosphorescence. The presence of surface-rich carboxyl groups on CDs determines the short-wavelength afterglow in their dispersed state while their high conjugation degree governs the long-wavelength afterglow in their aggregated state. Additionally, appropriate doping levels of CDs enhance color change phenomena during afterglow. Finally, by embedding CDs into different rigid matrix, the range of afterglow changes can be tailored arbitrarily within the visible light region. Leveraging these exceptional TDAC characteristics has allowed us to successfully develop advanced 4D coding technologies that facilitate multi-mode anti-counterfeiting and dynamic information encryption.

Carbon dots derived from organic drug molecules with improved therapeutic effects and new functions

Carbon dots (CDs) are new types of fluorescent nanomaterials with particle diameters of 1∼10 nm and have excellent photoluminescence (PL) properties, good biocompatibility, simple preparation methods and numerous raw materials; consequently, they are promising in the biomedical field. In recent years, to overcome drug resistance and toxic side effects of traditional organic drugs, the synthesis of CDs from drug molecules has become an effective strategy, which produces CDs with the same therapeutic effects as the raw drugs and even possessing new properties. At present, many CDs derived from organic drugs have been developed, which can be classified according to their sources such as antibiotics, anti-inflammatory drugs, and guanidine drugs. This article focuses on the progress of the above-mentioned drug-derived CDs compared with their drug precursors in terms of therapeutic efficacy, enhanced performance and new additional functions, with special attention to the structure-activity relationship between the drug precursors and the CD-based therapeutic agents. It demonstrates the feasibility of designing new drug-derived CDs for clinical applications, summarizes the shortcomings and research gaps of the existing work, and provides a reference for related work in the future.

Recent Advances of Carbon Dots: Synthesis, Plants Applications, Prospects, and Challenges

Nanomaterials and nanotechnology have garnered significant attention in the realm of agricultural production. Carbon dots (CDs), as a class of nanomaterials, play a crucial role in the field of plant growth due to their excellent properties. This review aims to summarize recent achievements on CDs, focusing on their methods of preparation and applications in plants systems. The effects of CDs on seed germination, growth, photosynthesis, nutritional quality, and stress resistance were studied. It has been demonstrated that CDs can promote seed germination and growth, as well as improve photosynthetic efficiency, ultimately leading to increase plants yield. The nutritional quality of the plants treated with CDs was significantly improved. Specifically, the levels of essential mineral elements, vitamins, amino acids, and other constituents that are beneficial to human health increased notably. Additionally, CDs show positive effects on augmenting plant resistance against environmental stresses, such as drought conditions, heavy metal toxicity, and high salinity. Finally, the prospects and challenges of the application of CDs in plant systems are also discussed, which provide a scientific basis for the future application of CDs in agricultural production.

Hawthorn carbon dots: a novel therapeutic agent for modulating body weight and hepatic lipid profiles in high-fat diet-fed mice

Obesity, a chronic metabolic disorder characterized by excessive body weight and adipose tissue accumulation, is intricately linked to a spectrum of health complications. It is driven by a confluence of factors, including gut microbiota dysbiosis, inflammation, and oxidative stress, which are pivotal in its pathogenesis. A multifaceted therapeutic strategy that targets these interrelated pathways is essential for effective obesity management. In this context, biomass-derived carbon dots have emerged as a promising avenue due to their diverse biological activities and potential in nanomedicine. Our study presents the synthesis of multi-modal hawthorn carbon dots (HCD), employing a green hydrothermal carbonization method that diverged from traditional stir-frying techniques. This eco-friendly approach facilitates the preparation of HCD, emphasizing the role of sugar compounds as the primary carbon source in their formation. In vitro assays demonstrate that HCD possess potent anti-inflammatory and antioxidant properties, which are crucial in combating the oxidative stress and inflammation associated with obesity. We further investigate the impact of HCD intervention in a high-fat diet (HFD)-induced obesity mouse model, employing both post-modeling and simultaneous modeling administration strategies. Our findings reveal that HCD treatment significantly reduces body weight and hepatic lipid accumulation in HFD mice, concurrently enhancing glucose tolerance and alleviating insulin resistance. Moreover, antibiotic perturbation experiments, complemented by bioinformatics analysis of colon microbiota, indicate that HCD substantially modulate gut microbiota composition. This modulation is associated with the amelioration of obesity-related conditions, suggesting that HCD may exert their beneficial effects through the regulation of gut microbiota, in addition to their anti-inflammatory and antioxidant activities. These multimodal mechanisms of action position HCD as a promising candidate for the prevention and treatment of obesity, offering a novel therapeutic strategy that targets the complex interplay of factors involved in this metabolic disorder.

MS-Based Characterization of Biomass-Derived Materials: Activated Carbons and Solvent Liquefaction Products

Mass spectrometry (MS) is a powerful analytical technique that is widely used to characterize a variety of analytes across diverse fields. In the area of biomass conversion, which is essential for producing sustainable materials and energy, the role of MS is pivotal. Biomass conversion processes, such as solvent liquefaction and pyrolysis, generate a wide range of industrially valuable materials including bio-based polymers, fuels, and activated carbons. However, the inherent complexity and heterogeneity of biomass and its transformation products pose significant analytical challenges. Advanced MS techniques, such as GC-MS, LC-MS, ICP-MS and MALDI-MS, are essential for a comprehensive analysis, providing detailed insights into the compositions, impurities, and potential inhibitors that influence process optimization and product quality. This review systematically explores recent advancements in MS-based methods for the analysis of biomass-derived products. We discuss fundamental innovations in biomass conversion processes and highlight the applications of various MS techniques in assessing the chemical complexity of these materials. The insights provided by MS techniques not only facilitate process optimization but also support the sustainable production of high-value materials from biomass, aligning with ongoing efforts to enhance environmental sustainability and resource efficiency.

Application of biomass carbon dots in food packaging

Since its discovery, carbon quantum dots (CDs) have been widely applied in cell imaging, drug delivery, biosensing, and photocatalysis due to their excellent water solubility, chemical stability, fluorescence stability biocompatibility, low toxicity, and preparation cost. However, the low fluorescence yield and poor surface structure limit the application of CDs. Heteroatom doping is considered an ideal method to improve CDs' optical and electrical properties. From this perspective, eco-friendly biomass and its derivatives are perfect carbon precursors for CDs because they contain the heteroatoms needed to modify CDs, and their complex chemical composition gives CDs a wide variety of surface functional groups. Besides, converting biomass waste into high-value-added CDs is also an innovation in biomass waste treatment. Therefore, this paper focuses on the carbon precursors of biomass CDs. At the same time, food packaging occupies an essential position in the industry, and fluorescent CDs with good fluorescence properties, high chemical stability, and good photobleaching properties have great application potential in packaging innovation techniques that have emerged in recent years, but relevant reports are scarce and scattered. Considering that the surface morphology, chemical structure, and optical and electrical properties of biomass CDs are primarily affected by the carbon precursors' chemical structure and preparation method, this paper also focuses on the synthesis method of biomass CDs and its application in anti-counterfeiting packaging, intelligent packaging, antioxidant packaging, and antibacterial packaging.

Green carbon dots derived from Zingiberis Rhizoma Carbonisatum alleviate ovalbumin-induced allergic rhinitis

Background

Allergic rhinitis (AR) affects up to 40% of the population, leading to significant healthcare expenditures. Current mainstream treatments, while effective, can lead to side effects and do not address the underlying immunological imbalances. Zingiberis Rhizoma Carbonisatum (ZRC), the partially charred product of Zingiberis Rhizoma (ZR), has been widely used clinically in China since ancient times to treat respiratory disorders.

Methods

Inspired by the similarity between high-temperature pyrolysis and carbonization processing of herbal medicine, ZRC derived CDs (ZRC-CDs) were extracted and purified through several procedures. Then, the physicochemical characteristics of CDs were delineated through a suite of characterization methods. Moreover, our investigation zeroed in on elucidating the ameliorative impacts of CDs on ovalbumin-induced rat models alongside their underlying mechanisms.

Results

ZRC-CDs with particle sizes ranging from 1.0 to 3.5 nm and rich surface functional groups. Additionally, we observed that ZRC-CDs significantly attenuated nasal symptoms and pathological damage in ovalbumin-induced AR rats, and modulated lipid metabolism and type 2 inflammatory responses. They also inhibit PI3K/AKT and JAK/STAT pathways, which are associated with metabolism and inflammation. Importantly, ZRC-CDs demonstrated high biocompatibility, underscoring their potential as a novel therapeutic agent.

Conclusion

ZRC-CDs offer a promising alternative for AR treatment and could help facilitate broader clinical use of the ZRC. In addition, the exploration of the inherent bioactivity of CDs can help to broaden their biological applications.