Strategic Assessment of Boron-Enriched Carbon Dots/Naproxen: Diagnostic, Toxicity, and In Vivo Therapeutic Evaluation.

Cancer is a significant global public health concern, ranking as the leading cause of mortality worldwide. This study thoroughly explores boron-doped carbon dots (B-CDs) through a simple/rapid microwave-assisted approach and their versatile applications in cancer therapy. The result was highly uniform particles with an average diameter of approximately 4 nm. B-CDs exhibited notable properties, including strong fluorescence with a quantum yield of 33%. Colloid stability tests revealed their robustness within a pH range of 6-12, NaCl concentrations up to 0.5 M, and temperatures ranging from 30 to 60 °C. The study also delved into the kinetics of naproxen release from B-CDs as a drug delivery system. The loading efficacy of naproxen exceeded 55.56%. Under varying pH conditions, the release of naproxen from B-CDs conformed to the Peppas-Sahlin model, demonstrating the potential of Naproxen-loaded CDs for cancer drug delivery. In vitro cytotoxicity assessments, conducted using the CCK-8 Assay and flow cytometry, consistently indicated low toxicity with average cell viability exceeding 80%. An in vivo toxicity test on female mice administered 20 mg/kg of B-CDs for 31 days revealed reversible histological changes in the liver and kidneys, while the pancreas remained unaffected. Importantly, B-CDs did not impact the mice's physical behavior, body weight, or survival. In vivo experiments targeting benzo(a)pyrene-induced fibrosarcoma demonstrated the efficacy of B-CDs as naproxen carriers in the treatment of cancer. This in vivo study provides a thorough comprehension of B-CDs synthesis and toxicity and their potential applications in cancer therapy and drug delivery systems.

Composition, Morphology, and Interface Engineering of 3D Cauliflower-Like Porous Carbon-Wrapped Metal Chalcogenides as Advanced Electrocatalysts for Quantum Dot-Sensitized Solar Cells.

Designing a low-cost, highly efficient, and stable electrocatalyst that can synergistically speed up the reduction of polysulfide electrolytes while operative for long periods in the open air is critical for the practical application of quantum dot-sensitized solar cells (QDSSCs), but it remains a challenging task. Herein, a simple, straightforward, and two-step nanocomposite engineering approach that simultaneously combines metallic copper chalcogenides (MC) either Cu2- x S or Cu2- x Se with S, N dual-doped carbon (SNC) sources for devising high-quality counter electrode (CE) film are reported. First, the hierarchically assembled MC nanostructures are obtained using microwave-assisted synthesis. Second, these MCs are embedded within an ordered macro-meso-microporous carbon matrix to obtain Cu2- x S@C or Cu2- x SeS@C CE. These CEs are demonstrated to have composition dependents crystal structure, surface morphologies, photovoltaic performance, and electrochemical properties. In terms of power conversion efficiency (PCE), the Cu2- x SeS@C (9.89%) and Cu2- x S@C-CE (8.96%) constructed QDSSCs outperform both Cu2- x Se (8.96%) and Cu2- x S-constructed (7.79%) QDSSCs, respectively. The enhanced PCE could be attributed to the synergistic interaction of S and N dopants with MC interfaces that can not only enrich electric conductivity, and a higher surface-to-volume ratio but also offers a 3D network for superior charge transport at the interface.

Synthesis of magnetofluorescence Gd-doped CuInS2/ZnS quantum dots with enhanced longitudinal relaxivity.

In this paper, we describe the rapid microwave-assisted synthesis of Gd(3+)-doped CuInS2 (Gd:CIS) quaternary quantum dots (q-dots), which integrate the functions of optical fluorescence and magnetic resonance imaging. Through passivation of ZnS shells around Gd:CIS cores, high-quality and robust photostable Gd:CIS/ZnS core/shell q-dots with enhanced quantum yields were obtained. The intensity and peak-to-peak linewidth of the electron spin resonance (EPR) signal were found to vary depending on the Gd(3+) concentration of Gd:CIS/ZnS. Benefiting from the incorporation of paramagnetic Gd(3+) ions, the formed q-dots exhibited well-resolved and strong signals of electron paramagnetic resonance and provided significant contrast enhancement in T1-weighted images owing to the remarkably high longitudinal relaxivity (r1 = 55.90 mM(-1) s(-1)) and low r2/r1 ratio (1.42), which are significantly higher than those of commercially available T1 contrast agents. We expect that this facile one-pot synthetic strategy can be extended to the preparation of other Cu-based sulfide quaternary nanomaterials.

Detection of arsenic(III) through pulsed laser-induced desorption/ionization of gold nanoparticles on cellulose membranes.

We have developed an assay based on gold nanoparticle-modified mixed cellulose ester membrane (Au NPs-MCEM) coupled with laser-induced desorption/ionization mass spectrometry (LDI-MS)-for the detection of arsenic(III) ions (arsenite, AsO2(-)) in aqueous solution. When the Au NPs reacted with lead ions (Pb(2+)) in alkaline solution (5 mM glycine-NaOH, pH 12), Au-Pb complexes, PbO, and Pb(OH) were formed immediately on the Au NP surfaces. The Pb species reacted rapidly with subsequently added AsO2(-) to form PbOAs2O3, (PbO)2As2O3, and/or (PbO)3As2O3 shells (2-5 nm) on the Au NPs' surfaces. As a result, significant observable aggregation of the Au NPs occurred in the solution. This Pb(2+)/Au NP probe allowed the detection of AsO2(-) at concentrations as low as 0.6 µM with high selectivity (at least 100-fold over other anions and metal ions). To further improve the sensitivity, we prepared Au NPs-MCEM for the LDI-MS-based detection of AsO2(-) ions. The intensity of the signal for the [Pb](+) ions in the mass spectra increased when the Au NPs-MCEM reacted with AsO2(-); in contrast, the intensity of the signal for [Au](+) ions decreased. Accordingly, the [Pb](+)/[Au](+) peak ratio increased upon increasing the AsO2(-) concentration over the range from 10 nM to 10 µM. The limit of detection at a signal-to-noise ratio of 3 was 2.5 nM, far below the action level of As (133 nM, ca. 10 ppb) permitted by the US EPA for drinking water. Relative to other nanoparticle-based arsenic sensors, this approach is rapid, specific, and sensitive; in addition, it can be applied to the detection of AsO2(-) in natural water samples (in this case, streamwater, lake water, tap water, groundwater, and mineral water).

Mass Spectrometry-Based Analyses of Carbon Nanodots: Structural Elucidation.

Carbon nanodots (CNDs) are nanomaterials with ubiquitous applications in health for diagnosis and treatments. The key to enhancing the applications of carbon nanodots in various fields lies on how deep its structure is understood. Here, we review the mass spectroscopy (MS) techniques employed for carbon nanodot analysis. We aimed to revive the use of MS to support the structural elucidation of carbon nanodots. General techniques used in nanomaterials characterization include laser desorption/ionization (LDI), matrix-assisted LDI (MALDI), inductively coupled plasma (ICP), and electrospray ionization (ESI) MS. For CNDs characterization, LDI-MS, MALDI-MS, and ESI-MS were employed. The techniques required further instrumentations of time-of-flight (TOF), for MALDI, and TOF, quadrupole (Q), and tandem (MS/MS) for ESI. LDI-MS could be applied to prove the surface and core structural composition of carbon nanodots. Meanwhile, MALDI-MS was used to elucidate the surface structures of CNDs. Finally, ESI-MS could provide significant insight into the carbon nanodots' structural composition and bonding patterns. In summary, MS could be combined with other techniques to unambiguously elucidate the structure of carbon nanodots.

Potential usage of boron modified carbon nanodots as a marker candidate for coronavirus disease (COVID-19) antibody detection.

The global outbreak of COVID-19 in December 2019 has highlighted rapid and accurate diagnostic tools for effective intervention. While the RT-PCR test offers 86 % sensitivity, uncertainties often require supplementary screening. This research investigates how carbon dots (CDs) can be utilized as markers for COVID-19 antibodies, taking advantage of their biocompatibility and low toxicity. CDs were synthesized using citric acid (CA) and APBA with boronic acid, enabling the detection of COVID-19 IgG antibodies with increased absorbance and fluorescence. Comprehensive analyses confirmed the successful synthesis of APBA-CDs, prompting further exploration of their impact on SARS-CoV-2 RNA. Increased absorbance levels were observed in categories K1, K2, and K3, attributed to the introduction of CDs into plasma, indicating effective binding of APBA-CDs to COVID-19 antibodies. In addition, the fluorescence tests consistently showed heightened levels across all categories, emphasizing the effective binding of APBA-CDs with COVID-19 antibodies, particularly in positive plasma samples. As a part of our analysis, we conducted a PCA test to validate the data, which revealed that APBA-CDs are specific to IgG+ antibodies. The results showed a sensitivity rate of 74 % and a specificity rate of 53 %, while, when tested for IgM antibodies, the sensitivity and specificity rates were 63 % and 27 %, respectively. These findings highlight the potential of APBA-CDs as a sensitive and specific marker for COVID-19 antibody detection, offering potential for diagnostic tool development.

Three-dimensional Au-MnO2 nanostructure as an agent of synergistic cancer therapy: chemo-/photodynamic and photothermal approaches.

The design of multimodal cancer therapy was focused on reaching an efficient process and minimizing harmful effects on patients. In the present study, the Au-MnO2 nanostructures have been successfully constructed and produced as novel multipurpose photosensitive agents simultaneously for photodynamic therapy (PDT), photothermal therapy (PTT), and chemodynamic therapy (CDT). The prepared AuNPs were conjugated with MnO2 NPs by its participation in the thermal decomposition process of KMnO4 confirmed by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy (FT-IR). The 16.5 nm Au-MnO2 nanostructure exhibited an absorbance at 438 nm, which is beneficial for application in light induction therapy due to the NIR band, as well as its properties of generating reactive oxygen species (ROS) associated with the 808 nm laser light for PDT. The photothermal transduction efficiency was calculated and compared with that of the non-irradiated nanostructure, in which it was found that the 808 nm laser induced a high efficiency of 83%, 41.5%, and 37.5% for PDT, PTT, and CDT, respectively. The results of DPBF and TMB assays showed that the efficiency of PDT and PTT was higher than that of CDT. The nanostructure also confirmed the time-dependent peroxidase properties at different H2O2, TMB, and H2TMB concentrations, promising good potency in applying nanomedicine in clinical cancer therapy.

Engineering H2O2 Self-Supplying Platform for Xdynamic Therapies via Ru-Cu Peroxide Nanocarrier: Tumor Microenvironment-Mediated Synergistic Therapy.

Of the most common, hypoxia, overexpressed glutathione (GSH), and insufficient H2O2 concentration in the tumor microenvironment (TME) are the main barriers to the advancment of reactive oxygen species (ROS) mediated Xdynamic therapies (X = photo, chemodynamic, chemo). Maximizing Fenton catalytic efficiency is crucial in chemodynamic therapy (CDT), yet endogenous H2O2 levels are not sufficient to attain better anticancer efficacy. Specifically, there is a need to amplify Fenton reactivity within tumors, leveraging the unique attributes of the TME. Herein, for the first time, we design RuxCu1-xO2-Ce6/CPT (RCpCCPT) anticancer nanoagent for TME-mediated synergistic therapy based on heterogeneous Ru-Cu peroxide nanodots (RuxCu1-xO2 NDs) and chlorine e6 (Ce6), loaded with ROS-responsive thioketal (TK) linked-camptothecin (CPT). The Ru-Cu peroxide NDs (RCp NDs, x = 0.50) possess the highest oxygen vacancy (OV) density, which grants them the potential to form massive Lewis's acid sites for peroxide adsorption, while the dispersibility and targetability of the NDs were improved via surface modification using hyaluronic acid (HA). In TME, RCpCCPT degrades, releasing H2O2, Ru2+/3+, and Cu+/2+ ions, which cooperatively facilitate hydroxyl radical (•OH) formation and deactivate antioxidant GSH enzymes through a cocatalytic loop, resulting in excellent tumor therapeutic efficacy. Furthermore, when combined with laser treatment, RCpCCPT produces singlet oxygen (1O2) for PDT, which induces cell apoptosis at tumor sites. Following ROS generation, the TK linkage is disrupted, releasing up to 92% of the CPT within 48 h. In vitro investigations showed that laser-treated RCpCCPT caused 81.5% cell death from PDT/CDT and chemotherapy (CT). RCpCCPT in cancer cells produces red-blue emission in images of cells taking them in, which allows for fluorescence image-guided Xdynamic treatment. The overall results show that RCp NDs and RCpCCPT are more biocompatible and have excellent Xdynamic therapeutic effectiveness in vitro and in vivo.

Formulation and Characteristics of Edible Oil Nanoemulsions Modified with Polymeric Surfactant for Encapsulating Curcumin.

Curcumin (Cur) is a beneficial phytochemical with numerous health advantages. However, its limited solubility in oil and poor stability hinder its potential for biomedical applications. In this study, we employed a mixture of food-grade Tween 60, a polymeric surfactant, and Span 60 to adjust the hydrophilic lipophilic balance number (HLBt) and prepared nanoemulsions (NEs) of coconut oil (Cc oil) as carriers for Cur. The effects of HLBt values, surfactant-to-oil ratio, and oil ratio on the physicochemical characteristics of the food-grade oil-NEs were investigated using dynamic light scattering, transmission electron microscopy, differential scanning calorimetry, fluorescence polarization spectroscopy, and viscometry. Increasing the addition ratio of Tween 60 in the NEs, thereby increasing the HLBt, resulted in a reduction in NE size and an improvement in their storage stability. The temperature and size of the phase transition region of the NEs decreased with increasing HLBt. NEs with higher HLBt exhibited a disordering effect on the intra-NE molecular packing of Cc oil. NEs with high HLBt displayed low viscosity and demonstrated nearly Newtonian fluid behavior, while those with lower HLBt exhibited pseudoplastic fluid behavior. Cur was effectively encapsulated into the Cc oil-NEs, with higher encapsulation efficiency observed in NEs with higher HLBt values. Furthermore, the Cur remaining activity was significantly enhanced through encapsulation within stable NEs. The biocompatibility of the Cc oil-NEs was also demonstrated in vitro. In summary, this study highlights the preparation of stable NEs of Cc oil by adjusting the HLBt using Tween 60, facilitating effective encapsulation of Cur. These findings provide valuable insights for the development of Cur carriers with improved solubility, stability, and bioavailability.

Development of Two-Dimensional Functional Nanomaterials for Biosensor Applications: Opportunities, Challenges, and Future Prospects.

New possibilities for the development of biosensors that are ready to be implemented in the field have emerged thanks to the recent progress of functional nanomaterials and the careful engineering of nanostructures. Two-dimensional (2D) nanomaterials have exceptional physical, chemical, highly anisotropic, chemically active, and mechanical capabilities due to their ultra-thin structures. The diversity of the high surface area, layered topologies, and porosity found in 2D nanomaterials makes them amenable to being engineered with surface characteristics that make it possible for targeted identification. By integrating the distinctive features of several varieties of nanostructures and employing them as scaffolds for bimolecular assemblies, biosensing platforms with improved reliability, selectivity, and sensitivity for the identification of a plethora of analytes can be developed. In this review, we compile a number of approaches to using 2D nanomaterials for biomolecule detection. Subsequently, we summarize the advantages and disadvantages of using 2D nanomaterials in biosensing. Finally, both the opportunities and the challenges that exist within this potentially fruitful subject are discussed. This review will assist readers in understanding the synthesis of 2D nanomaterials, their alteration by enzymes and composite materials, and the implementation of 2D material-based biosensors for efficient bioanalysis and disease diagnosis.

Molybdenum-oxo-sulfide quantum dot-based nanocarrier: Efficient generation of reactive oxygen species via photo/chemodynamic therapy and stimulus-induced drug release.

The fabrication of multifunctional nano-therapies has increased gradually to strengthen the therapeutic performance and minimize adverse effects of traditional cancer treatment strategies. Currently, we have designed a facile preparation drug-loaded nanocarrier for multimodal cancer therapy upon external stimuli. First, defect-rich molybdenum oxo-sulfide (MoOxS2-x) quantum dots (QDs) was synthesized via rapid biomineralization techniques with superior optical quantum yield reaching upto 37.28%. The presence of the Fenton ion, Mo+IV/+VI, enables MoOxS2-x QDs to efficiently catalyze peroxide solutions to produce •OH radicals for chemodynamic treatment (CDT) and also deactivate the intracellular glutathione (GSH) enzymes through redox reaction for boosted reactive oxygen species (ROS)-mediated therapies. In addition, upon laser combination, MoOxS2-x QDs generate ROS for photodynamic therapy (PDT). Also, due to a large amount of sulfide content, MoOxS2-x QDs showed excellent H2S gas release in acidic pH for cancer gas therapy. Then, MoOxS2-x QDs was further conjugated with ROS-responsive thioketal linked Camptothecin (CPT-TK-COOH) drug, forming a multitargeted MoOxS2-xCPT anticancer agent with better drug-loading efficiency (38.8%). After triggering the ROS generation through the CDT and PDT mechanisms, the thioketal linkage was disrupted, releasing up to 79% of the CPT drug in 48 h. Besides, in vitro experiments verified that MoOxS2-x QDs possess higher biocompatibility with 4T1 and HeLa cells but also showed considerable toxicity in the presence of laser/H2O2, resulting in 84.45% cell death through PDT/CDT and chemotherapeutic effects. Therefore, the designed MoOxS2-xCPT exhibited outstanding therapeutic benefits for image-guided cancer therapy.

Multifunctional manganese oxide-based nanocomposite theranostic agent with glucose/light-responsive singlet oxygen generation and dual-modal imaging for cancer treatment.

Development of tumor microenvironment (TME) modifying nanomedicine with cooperative effect between multiple stimuli responsive therapeutic modalities is necessary to achieve lower dosage induced tumor specific therapy. Accordingly, herein, a multifunctional MnOx NSs@BSA-IR780-GOx nanocomposite (MBIG NCs) is developed to modulate the oxidative stress in TME, and thus attain higher therapeutic efficacy. In the presence of glucose, the as-synthesized MBIG NCs are served as a chemodynamic agents and generated reactive oxygen species (ROS) by self-activation through a cascade of reactions from glucose oxidase (GOx) and manganese oxide nanosheets (MnOx NSs). Also, the MBIG NCs demonstrated excellent photodynamic properties upon irradiation with 808 nm laser owing to the presence of IR780. The combination of glucose-mediated chemodynamic and light-mediated photodynamic properties generated higher ROS than that obtained with individual stimuli. Further, the MBIG NCs exhibited photothermal effect with conversion efficiency of 33.8 %, which helped to enhance the enzymatic activities. In in vitro studies, the MBIG NCs exhibited good biocompatibility to cancerous and non-cancerous cells under non-stimulus conditions. Nevertheless, in the presence of glucose and light stimuli, they triggered more than 90 % cell toxicity at 200 ppm concentration via the cooperative effect between starvation therapy, chemodynamic therapy, and phototherapy. Furthermore, the MBIG NCs demonstrated magnetic resonance and fluorescence imaging properties. These results are suggesting that MBIG NCs would be potential theranostic agents to for cancer diagnosis and target specific therapy. More importantly, the fabrication process is paving a way to improve the aqueous dispersibility, stability, and bio-applicability of MnOx NSs and IR780.

Highly efficient visible light active ZnO/Cu-DPA composite photocatalysts for the treatment of wastewater contaminated with organic dye.

Industrial effluents are a leading major threat for water contamination, subsequently which results in severe health associated risks. Hence, purifying wastewater before releasing into the water resources is essential to avoid contamination. In this study, ZnO/Cu-DPA nano-composites were prepared by altering the percentage of Cu-DPA (20%, 30%, 40%, and 50% which are denoted to be ZnO/20%Cu-DPA, ZnO/30%Cu-DPA, ZnO/40%Cu-DPA and ZnO/50%Cu-DPA) using a simple mechanical grinding process. Several spectroscopic studies were employed such as electron paramagnetic analysis (EPR), powdered X-ray diffractometer (PXRD), UV-Vis absorbance spectroscopy, Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscope to characterize these nano-composites. The photo-catalytic activities of the prepared nano-composites were studied by degrading MB under visible light irradiation. ZnO, ZnO/20%Cu-DPA, ZnO/30%Cu-DPA, ZnO/40%Cu-DPA and ZnO/50%Cu-DPA degradation efficiencies were determined to be 71.8, 78.5, 77.1, and 66.1%, respectively. Among the composite catalysts, the ZnO/20%Cu-DPA coupled system are demonstrated the best efficiency (87%) for photo-degradation of MB within 80 min when exposed to visible light. The ZnO/Cu-DPA nano-composites had a greater MB photodegradation efficiency than pristine ZnO owing to p-n heterojunction in the linked system. Under visible light irradiation, the ZnO/20%Cu-DPA catalysed the conversion of dissolved O2 to hydroxyl radicals (OH·), triggering the reduction of MB. This suggests that ·OH is the primary specific active radical involved in the photo-catalytic decomposition of MB. Furthermore, EPR analysis indicates the existence of ·OH in the photo-catalytic system. The proposed nano-composites (ZnO/20%Cu-DPA) reusability was investigated across three cycles as the most efficient photo-catalyst. The results show that, the ZnO/Cu-DPA nano-catalyst is a potential candidate for the remediation of dirty water.

Preclinical Assessment of Enhanced Chemodynamic Therapy by an FeMnOx-Based Nanocarrier: Tumor-Microenvironment-Mediated Fenton Reaction and ROS-Induced Chemotherapeutic for Boosted Antitumor Activity.

In recent studies, iron-containing Fenton nanocatalysts have demonstrated significant promise for clinical use due to their effective antitumor activity and low cytotoxicity. A new approach was reported in this work utilizing cation exchange synthesis to fabricate FeMnOx nanoparticles (NPs) that boost Fenton reactions and responses to the tumor microenvironment (TME) for chemodynamic therapy (CDT) and chemotherapy (CT). Within the TME, the redox metal pair of Fe2+/Mn2+ helps break down endogenous hydrogen peroxide (H2O2) into very harmful hydroxyl radicals (•OH) while simultaneously deactivating glutathione (GSH) to boost CDT performance. To further enhance the therapeutic potential, FeMnOx NPs were encapsulated with thioketal-linked camptothecin (CPT-TK-COOH), a reactive oxygen species (ROS)-responsive prodrug, achieving a high CPT-loading capacity of up to 51.1%. Upon ROS generation through the Fenton reaction, the prodrug TK linkage was disrupted, releasing 80% of the CPT payload within 48 h. Notably, FeMnOx@CPT exhibited excellent dual-modal imaging capabilities, enabling magnetic resonance and fluorescence imaging for image-guided therapy. In vitro studies showed the cytocompatibility of FeMnOx NPs using MDA-Mb-231 and 4T1 cells, but in the presence of H2O2, they induced significant cytotoxicity, resulting in 80% cell death through CDT and CT effects. Upon intravenous administration, FeMnOx@CPT displayed remarkable tumor accumulation, which enhanced tumor suppression in xenografts through improved CDT and CT effects. Moreover, no significant adverse effects were observed in the FeMnOx NP-treated animals. In the current study, the FeMnOx@CPT anticancer platform, with its boosted •OH-producing capability and ROS-cleavable drug release, has been validated utilizing in vitro and animal studies, suggesting its capacity as a viable strategy for clinical trials.

High performance carbon dots based prodrug Platform: Image-Guided photodynamic and chemotherapy with On-Demand drug release upon laser irradiation.

The design of therapeutic nanoplatforms based on fluorescent carbon dots (CDs) has become a viable strategy because of their aqueous solubility, biocompatibility, and ease of further functionalization. By doping various heteroatoms into pristine CDs structures, we synthesized N-, Cl-, and S-doped CDs (NClS/CDs), as well as Se-, N-, and Cl-doped CDs (NClSe/CDs) with superior optoelectronic properties using rapid and straightforward microwave heating. The quantum efficiencies of these NClS/CDs and NClSe/CDs were enhanced to 30.7 % and 42.9 %, respectively, compared to those of undoped CDs (0.66 %). Owing to their better light absorption properties, NClS/CDs efficiently produced reactive oxygen species (ROS) under 532 nm laser irradiation for photodynamic therapy (PDT). Considering the ROS generation and surface carrier abilities of NClS/CDs, we designed the loading of camptothecin (CPT) drug via a thioketal linker (TL), resulting in h/CDs@CPT nanovesicles (NVs) with a drug-loading efficiency of 46.5 %. Under laser irradiation in an acidic environment, ROS-triggered CPT release was observed, with 50.2 % of CPT released following the breakdown of the ROS-sensitive TL. In vitro cellular studies revealed that h/CDs@CPT NVs possessed minimal cytotoxicity toward HeLa and 4 T1 cancer cells, despite the high clinical efficacy of PDT and ROS-induced chemotherapeutic response under laser treatment. Confocal microscopy of HeLa and 4 T1 cells revealed that h/CDs@CPT NVs produced red-emissive photographs for potential cancer cell detection. Therefore, our study presents an image-guided PDT and chemotherapeutic platform based on h/CDs@CPT NVs, which will be an attractive candidate for future cancer treatment.

A Perspective on Using Organic Molecules Composing Carbon Dots for Cancer Treatment.

Fluorescent Carbon dots (CDs) derived from biologically active sources have shown enhanced activities compared to their precursors. With their prominent potentiality, these small-sized (<10nm) nanomaterials could be easily synthesized from organic sources either by bottom-up or green approach. Their sources could influence the functional groups present on the CDs surfaces. A crude source of organic molecules has been used to develop fluorescent CDs. In addition, pure organic molecules were also valuable in developing practical CDs. Physiologically responsive interaction of CDs with various cellular receptors is possible due to the robust functionalization on their surface. In this review, we studied various literatures from the past ten years that reported the potential application of carbon dots as alternatives in cancer chemotherapy. The selective cytotoxic nature of some of the CDs towards cancer cell lines suggests the role of surface functional groups towards selective interaction, which results in over-expressed proteins characteristic of cancer cell lines. It could be inferred that cheaply sourced CDs could selectively bind to overexpressed proteins in cancer cells with the ultimate effect of cell death induced by apoptosis. In most cases, CDs-induced apoptosis directly or indirectly follows the mitochondrial pathway. Therefore, these nanosized CDs could serve as alternatives to the current kinds of cancer treatments that are expensive and have numerous side effects.

Thermally constructed stable Zn-doped NiCoOx-z alloy structures on stainless steel mesh for efficient hydrogen production via overall hydrazine splitting in alkaline electrolyte.

Hydrogen has a high energy density of approximately 120 to 140 MJ kg-1, which is very high compared to other natural energy sources. However, hydrogen generation through electrocatalytic water splitting is a high electricity consumption process due to the sluggish oxygen evolution reaction (OER). As a result, hydrogen generation through hydrazine-assisted water electrolysis has recently been intensively investigated. The hydrazine electrolysis process requires a low potential compared to the water electrolysis process. Despite this, the utilization of direct hydrazine fuel cells (DHFCs) as portable or vehicle power sources necessitates the development of inexpensive and effective anodic hydrazine oxidation catalysts. Here, we prepared oxygen-deficient zinc-doped nickel cobalt oxide (Zn-NiCoOx-z) alloy nanoarrays on stainless steel mesh (SSM) using a hydrothermal synthesis method followed by thermal treatment. Furthermore, the prepared thin films were used as electrocatalysts, and the OER and hydrazine oxidation reaction (HzOR) activities were investigated in three- and two-electrode systems. In a three-electrode system, Zn-NiCoOx-z/SSM HzOR requires -0.116 V (vs RHE) potential to achieve a 50 mA cm-2 current density, which is dramatically lower than the OER potential (1.493 V vs RHE). In a two-electrode system (Zn-NiCoOx-z/SSM(-)∥Zn-NiCoOx-z/SSM(+)), the overall hydrazine splitting potential (OHzS) required to reach 50 mA cm-2 is only 0.700 V, which is dramatically less than the required potential for overall water splitting (OWS). These excellent HzOR results are due to the binder-free oxygen-deficient Zn-NiCoOx-z/SSM alloy nanoarray, which provides a large number of active sites and improves the wettability of catalysts after Zn doping.

Multifunctional MnCuInSe/ZnS quantum dots for bioimaging and photodynamic therapy.

In this work, manganese (Mn)-doped CuInSe quantum dots (QDs) with a ZnS passivation layer (MnCuInSe/ZnS) have been synthesized via a one-pot microwave-assisted hydrothermal reaction using glutathione (GSH) as a stabilizer. The MnCuInSe/ZnS core-shell QDs combine magnetic resonance imaging (MRI), excitation-dependent red emission, and reactive oxygen radical generation functions, in which regulation of Mn2+ incorporation leads to synergistic imaging and therapeutic modalities. The MnCuInSe/ZnS QDs exhibit high colloidal and photochemical stability in simulated media and at different pH values. An r2/r1 ratio of 9.99 was calculated from MRI studies suggesting their potential application as dual-modal imaging agents. Based on in vitro tests on Hela, B16, and HepG2 cell lines, it is apparent that MnCuInSe/ZnS QDs impose no significant cytotoxicity in the dark, while they can efficiently generate singlet oxygen radicals for photodynamic therapy of cancers, killing more than 80% of B16 cells within 5 min of laser irradiation (671 nm, 1 W cm-2). Furthermore, in vitro fluorescence imaging and cellular internalization of QDs are examined to visualize cellular uptake and in situ ROS generation. Therefore, this research exemplifies a new set of multifunctional chalcogenide QDs for theranostic applications.

Highly Luminescent, Stable, and Red-Emitting CsMgxPb1-xI3 Quantum Dots for Dual-Modal Imaging-Guided Photodynamic Therapy and Photocatalytic Activity.

In this study, for the first time, red-emitting CsMgxPb1-xI3 quantum dots (QDs) are prepared by doping with magnesium (Mg) ions via the one-pot microwave pyrolysis technique. The X-ray diffraction and X-ray photoelectron spectroscopy results have confirmed partial substitution of Pb2+ by Mg2+ inside the CsPbI3 framework. The as-synthesized CsMgxPb1-xI3 QDs have exhibited excellent morphology, higher quantum yield (upto ∼89%), better photostability and storage stability than undoped CsPbI3. Next, the bioavailability of as-synthesized hydrophobic CsMgxPb1-xI3 QDs is improved by encapsulating them into gadolinium-conjugated pluronic 127 (PF127-Gd) micelles through hydrophobic interactions (PQD@Gd). The optical properties of perovskite quantum dots (PQDs) and the presence of Gd could endow the PQD@Gd with fluorescence imaging, magnetic resonance imaging (MRI), and phototherapeutic properties. Accordingly, the MRI contrasting effects of PQD@Gd nanoagents are demonstrated by employing T1 and T2 studies, which validated that PQD@Gd nanoagents had superior MR contrasting effect with a r2/r1 ratio of 1.38. In vitro MRI and fluorescence imaging analyses have shown that the PQD@Gd nanoagents are internalized into the cancer cells via a caveolae-mediated endocytosis pathway. The PQD@Gd nanoagents have exhibited excellent biocompatibility even at concentrations as high as 450 ppm. Interestingly, the as-prepared PQD@Gd nanoagents have efficiently produced cytotoxic reactive oxygen species in the cancer cells under 671 nm laser illumination and thereby induced cell death. Moreover, the PQD@Gd nanoagent also demonstrated excellent photocatalytic activity toward organic pollutants under visible light irradiation. The organic pollutants rhodamine b, methyl orange, and methylene blue were degraded by 92.11, 89.21, and 76.21%, respectively, under 60, 80, and 100 min, respectively, irradiation time. The plausible mechanism for the photocatalytic activity is also elucidated. Overall, this work proposes a novel strategy to enhance the optical properties, stability, and bioapplicability of PQDs. The multifunctional PQD@Gd nanoagents developed in this study could be the potential choice of components not only for cancer therapy due to dual-modal imaging and photodynamic therapeutic properties but also for organic pollutant or bacterial removal due to excellent photocatalytic properties.

Brightly luminescent (NH4)xCs1-xPbBr3 quantum dots for in vitro imaging and efficient photothermal ablation therapy.

Herein, we report for the first time a facile strategy for the highly efficient (NH4)xCs1-xPbBr3 quantum dots (QDs). By modulating the amount of ammonium, (NH4)xCs1-xPbBr3 QDs with different photoluminescence (PL) quantum yields (QY) were synthesized. The results of X-ray diffraction and X-ray photoelectron spectroscopy showed that the crystal structure of (NH4)xCs1-xPbBr3 was altered by incorporation of NH4+ cations into the CsPbBr3 lattice. The (NH4)xCs1-xPbBr3 QDs showed enhanced PL QY, higher photostability, and long-term storage stability compared to CsPbBr3 QDs. Furthermore, (NH4)xCs1-xPbBr3 QDs could be conjugated with a photothermal dye (IR780) via a one-pot reaction using poly(styrene-co-maleic anhydride) and IR780-MPTS. To the best of our knowledge, the present work is the first attempt integrating perovskite QDs and phototherapeutic molecules into one system (abbreviated as PQD-IR780), demonstrating good water dispersibility and high photothermal conversion efficiency of 57.85%. In vitro experiments performed to examine subcellular uptake showed high fluorescence brightness was observed in HeLa, B16F1, and HepG2 cancer cells cultured with PQD-IR780. The results indicate that the internalization mechanism for uptaking of PQD-IR780 inside HeLa cells is energy-dependent and caveolin-mediated endocytosis. The in vitro cell viability assays and photothermal therapy revealed that PQD-IR780 showed good biocompatibility and can induce hyperthermia upon laser irradiation.