Polymer-Conjugated Carbon Nanotubes for Biomolecule Loading

Carbon Nanomaterials for Plant Priming through Mechanostimulation: Emphasizing the Role of Shape

The use of nanomaterials to improve plant immunity for sustainable agriculture is gaining increasing attention; yet, the mechanisms involved remain unclear. In contrast to metal-based counterparts, carbon-based nanomaterials do not release components. Determining how these carbon-based nanomaterials strengthen the resistance of plants to diseases is essential as well as whether shape influences this process. Our study compared single-walled carbon nanotubes (SWNTs) and graphene oxide (GO) infiltration against the phytopathogen Pseudomonas syringae pv tomato DC3000. Compared with plants treated with GO, plants primed with SWNTs showed a 29% improvement in the pathogen resistance. Upon nanopriming, the plant displayed wound signaling with transcriptional regulation similar to that observed under brushing-induced mechanostimulation. Compared with GO, SWNTs penetrated more greatly into the leaf and improved transport, resulting in a heightened wound response; this effect resulted from the tubular structure of SWNTs, which differed from the planar form of GO. The shape effect was further demonstrated by wrapping SWNTs with bovine serum albumin, which masked the sharp edges of SWNTs and resulted in a significant decrease in the overall plant wound response. Finally, we clarified how the local wound response led to systemic immunity through increased calcium ion signaling in distant plant areas, which increased the antimicrobial efficacy. In summary, our systematic investigation established connections among carbon nanomaterial priming, mechanostimulation, and wound response, revealing recognition patterns in plant immunity. These findings promise to advance nanotechnology in sustainable agriculture by strengthening plant defenses, enhancing resilience, and reducing reliance on traditional chemicals.

Carbon Nanomaterial Fluorescent Probes and Their Biological Applications

Fluorescent carbon nanomaterials have broadly useful chemical and photophysical attributes that are conducive to applications in biology. In this review, we focus on materials whose photophysics allow for the use of these materials in biomedical and environmental applications, with emphasis on imaging, biosensing, and cargo delivery. The review focuses primarily on graphitic carbon nanomaterials including graphene and its derivatives, carbon nanotubes, as well as carbon dots and carbon nanohoops. Recent advances in and future prospects of these fields are discussed at depth, and where appropriate, references to reviews pertaining to older literature are provided.

Nanoplatforms for the Delivery of Nucleic Acids into Plant Cells

Nanocarriers are widely used for efficient delivery of different cargo into mammalian cells; however, delivery into plant cells remains a challenging issue due to physical and mechanical barriers such as the cuticle and cell wall. Here, we discuss recent progress on biodegradable and biosafe nanomaterials that were demonstrated to be applicable to the delivery of nucleic acids into plant cells. This review covers studies the object of which is the plant cell and the cargo for the nanocarrier is either DNA or RNA. The following nanoplatforms that could be potentially used for nucleic acid foliar delivery via spraying are discussed: mesoporous silica nanoparticles, layered double hydroxides (nanoclay), carbon-based materials (carbon dots and single-walled nanotubes), chitosan and, finally, cell-penetrating peptides (CPPs). Hybrid nanomaterials, for example, chitosan- or CPP-functionalized carbon nanotubes, are taken into account. The selected nanocarriers are analyzed according to the following aspects: biosafety, adjustability for the particular cargo and task (e.g., organelle targeting), penetration efficiency and ability to protect nucleic acid from environmental and cellular factors (pH, UV, nucleases, etc.) and to mediate the gradual and timely release of cargo. In addition, we discuss the method of application, experimental system and approaches that are used to assess the efficiency of the tested formulation in the overviewed studies. This review presents recent progress in developing the most promising nanoparticle-based materials that are applicable to both laboratory experiments and field applications.

Graphene-encapsulated iron nanoparticles as a non-viral vector for gene delivery into melanoma cells

The rapid progress of nanotechnology has led to use different nanomaterials for biomedical applications. Among them, graphene-encapsulated magnetic nanoparticles (GEMNS) are recognized as next generation carbon nanomaterials in translation cancer research. In this study, we utilized green fluorescence protein (GFP) expression plasmid DNA (pDNA) and GEMNS decorated with branched polyethyleneimine (PEI) to yield a novel transporter (GEMNS-PEI/pDNA) for gene delivery into melanoma cells (B16F10). The efficiency of transfection was examined using PCR and confocal microscopy. The studies show that the as-designed GEMNS-PEI construct is successfully used to transfect the melanoma cells with pDNA and it should be considered as a potent non-viral vector for introducing naked nucleic acids into eucaryotic cells.

Single-Site Fe-N-C Atom Based Carbon Nanotubes for Mutually Promoted and Synergistic Oncotherapy

A carbon nanotube (CNT) supported single-site Fe-N-C catalyst (CNTs/Fe-N-C) exhibited attractive properties in peroxidase (POD)-like activity and photothermal effect. Herein, we designed a therapeutic platform by wrapping doxorubicin (DOX) in mesoporous CNTs/Fe-N-C with the cell membrane (CM) of breast cancer. The ultimate nanoagent (CNTs/Fe-N-C/DOX/CM) exhibited high antitumor activity on account of its efficient catalytic ability, increased drug release rates, and significant photothermal effect. Due to the POD-like activity, CNTs/Fe-N-C could effectively catalyze hydrogen peroxide (H₂O₂) into cytotoxic hydroxyl radicals (^•OH) for chemodynamic therapy (CDT) of the tumor. Besides, the released DOX not only merely induced the diagnosis of the tumor cells for chemotherapy (CT) but also generated H₂O₂ to promote CDT. Moreover, the photothermal effect of the nanoagent could use for photothermal therapy (PTT). The increasing temperature was conducive to the release of DOX from micropore into the cell, which indirectly enhanced CT and CDT effects. As an intelligent and multifunctional drug delivery platform, the present CNTs/Fe-N-C/DOX/CM nanoagent could be engineered with synergistic treatments and favorable biosafety, which provides a promising paradigm in site-specific antitumor treatment and biomedicine.

Targeted Carbon Nanostructures for Chemical and Gene Delivery to Plant Chloroplasts

Nanotechnology approaches for improving the delivery efficiency of chemicals and molecular cargoes in plants through plant biorecognition mechanisms remain relatively unexplored. We developed targeted carbon-based nanomaterials as tools for precise chemical delivery (carbon dots, CDs) and gene delivery platforms (single-walled carbon nanotubes, SWCNTs) to chloroplasts, key organelles involved in efforts to improve plant photosynthesis, assimilation of nutrients, and delivery of agrochemicals. A biorecognition approach of coating the nanomaterials with a rationally designed chloroplast targeting peptide improved the delivery of CDs with molecular baskets (TP-β-CD) for delivery of agrochemicals and of plasmid DNA coated SWCNT (TP-pATV1-SWCNT) from 47% to 70% and from 39% to 57% of chloroplasts in leaves, respectively. Plants treated with TP-β-CD (20 mg/L) and TP-pATV1-SWCNT (2 mg/L) had a low percentage of dead cells, 6% and 8%, respectively, similar to controls without nanoparticles, and no permanent cell and chloroplast membrane damage after 5 days of exposure. However, targeted nanomaterials transiently increased leaf H₂O₂ (0.3225 μmol gFW^-1) above control plant levels (0.03441 μmol gFW^-1) but within the normal range reported in land plants. The increase in leaf H₂O₂ levels was associated with oxidative damage in whole plant cell DNA, a transient effect on chloroplast DNA, and a decrease in leaf chlorophyll content (-17%) and carbon assimilation rates at saturation light levels (-32%) with no impact on photosystem II quantum yield. This work provides targeted delivery approaches for carbon-based nanomaterials mediated by biorecognition and a comprehensive understanding of their impact on plant cell and molecular biology for engineering safer and efficient agrochemical and biomolecule delivery tools.