Dysphania ambrosioides (L.) Mosyakin and Clemants: bridging traditional knowledge, photochemistry, preclinical investigations, and toxicological validation for health benefits.

Dysphania ambrosioides L. (Chenopodiaceae) is a Moroccan medicinal plant known locally as "M'Khinza." It is widely used in traditional medicine to treat numerous ailments, such as diabetes, digestive disorders, fever, fertility problems, immune disorders, hypertension, bronchitis, respiratory conditions, pharyngitis, cough, and flu. As part of this review, comprehensive preclinical investigations, including in vitro, in vivo, and in silico studies, were conducted to better understand the mechanisms of action of D. ambrosioides. Additionally, the phytochemical profile of the plant was examined, highlighting the presence of certain bioactive secondary metabolites. The information was gathered from electronic data sources such as Web of Science, PubMed, Science Direct, Scopus, Springer Link, and Google Scholars. Numerous studies have mentioned the pharmacological properties of D. ambrosioides, including its antioxidant, anti-inflammatory, antiparasitic, antiviral, antibacterial, and antifungal activities. Furthermore, research has also suggested its potential as an anticancer, antidiabetic, and vasorelaxant agent. Phytochemical characterization of D. ambrosioides has revealed the presence of over 96 major bioactive compounds, including terpenoids, polyphenols, flavonoids, alkaloids, and fatty acids. As for the toxicity of this plant, it is dose-dependent. Furthermore, more in-depth pharmacological studies are needed to establish the mechanisms of action of this plant more accurately before considering clinical trials. In conclusion, this review highlights the traditional use of D. ambrosioides in Moroccan medicine and emphasizes its potential pharmacological properties. However, to fully harness its therapeutic potential, further research, both in terms of chemistry and pharmacology, is necessary. These future studies could help identify new active compounds and provide a better understanding of the mechanisms of action of this plant, thus opening new prospects for its pharmaceutical application.

Smart contact lens systems for ocular drug delivery and therapy.

Ocular drug delivery and therapy systems have been extensively investigated with various methods including direct injections, eye drops and contact lenses. Nowadays, smart contact lens systems are attracting a lot of attention for ocular drug delivery and therapy due to their minimally invasive or non-invasive characteristics, highly enhanced drug permeation, high bioavailability, and on-demand drug delivery. Furthermore, smart contact lens systems can be used for direct light delivery into the eyes for biophotonic therapy replacing the use of drugs. Here, we review smart contact lens systems which can be classified into two groups of drug-eluting contact lens and ocular device contact lens. More specifically, this review covers smart contact lens systems with nanocomposite-laden systems, polymeric film-incorporated systems, micro and nanostructure systems, iontophoretic systems, electrochemical systems, and phototherapy systems for ocular drug delivery and therapy. After that, we discuss the future opportunities, challenges and perspectives of smart contact lens systems for ocular drug delivery and therapy.

Deep learning study of tyrosine reveals that roaming can lead to photodamage.

Amino acids are among the building blocks of life, forming peptides and proteins, and have been carefully 'selected' to prevent harmful reactions caused by light. To prevent photodamage, molecules relax from electronic excited states to the ground state faster than the harmful reactions can occur; however, such photochemistry is not fully understood, in part because theoretical simulations of such systems are extremely expensive-with only smaller chromophores accessible. Here, we study the excited-state dynamics of tyrosine using a method based on deep neural networks that leverages the physics underlying quantum chemical data and combines different levels of theory. We reveal unconventional and dynamically controlled 'roaming' dynamics in excited tyrosine that are beyond chemical intuition and compete with other ultrafast deactivation mechanisms. Our findings suggest that the roaming atoms are radicals that can lead to photodamage, offering a new perspective on the photostability and photodamage of biological systems.

Photochemistry of (Z)-Isovinylneoxanthobilirubic Acid Methyl Ester, a Bilirubin Dipyrrinone Subunit: Femtosecond Transient Absorption and Stimulated Raman Emission Spectroscopy.

Bilirubin (BR) is an essential metabolite formed by the catabolism of heme. Phototherapy with blue-green light can be applied to reduce high concentrations of BR in blood and is used especially in the neonatal period. In this work, we studied the photochemistry of (Z)-isovinylneoxanthobilirubic acid methyl ester, a dipyrrinone subunit of BR, by steady-state absorption, femtosecond transient absorption, and stimulated Raman spectroscopies. Both the (Z)- and (E)-configurational isomers of isovinylneoxanthobilirubic acid undergo wavelength-dependent and reversible photoisomerization. The isomerization from the excited singlet state is ultrafast (the lifetimes of (Z)- and (E)-isomers were found to be ∼0.9 and 0.1 ps, respectively), and its efficiencies increase with increased photon energy. In addition, we studied sensitized photooxidation of the dipyrrinone subunit by singlet oxygen that leads to the formation of propentdyopents. Biological activities of these compounds, namely, effects on the superoxide production, lipoperoxidation, and tricarboxylic acid cycle metabolism, were also studied. Finally, different photochemical and biological properties of this BR subunit and its structural analogue, (Z)-vinylneoxanthobilirubic acid methyl ester, studied before, are discussed.

Review of the Phytochemistry and Biological Activity of Cissus incisa Leaves.

BACKGROUND: Cissus incisa is a Vitaceae with a pantropical distribution. In northern Mexico, its leaves have traditionally been used to treat skin infections, abscesses and tumors. Despite its medicinal uses, few studies have been reported. OBJECTIVE: The objective of this study is to summarize the phytochemical and biological studies carried out so far on the leaves of C. incisa, since this part of the plant is the one frequently used, and awaken scientific interest towards the plant. METHODS: Since C. incisa was an undocumented species, most of the information comes from reports of our research group. Databases, books, and websites were also consulted. The information collected was organized and presented in a synthesized way. Plant name was checked with the database "The Plant List". RESULTS: 171, 260, and 114 metabolites were identified by UHPLC-QFTOF-MS in the hexane, chloroform/ methanol, and aqueous extracts, respectively. Fatty acyls, sphingolipids, sterols, glycerolipids, prenol lipids, and terpenes are common metabolites found in these extracts. 2-(2´-hydroxydecanoyl amino)-1,3,4-hexadecanotriol-8-ene, 2,3-dihydroxypropyl tetracosanoate, ß-sitosterol, ß-sitosterol-D-glucopyranoside, α-amyrin-3-O-ß-D-glucopyranoside were also isolated and characterized. Extracts, phytocompounds and semi-synthetic derivatives showed antimicrobial activity against multi-drug resistant bacteria and various cancer cell lines. Results from Perturbation- Theory-Machine Learning-Information-Fusion model (PTMLIF), molecular docking, and vesicular contents assay identified potential targets on the cell membrane, suggesting an antibacterial mechanism of action for ceramides from C. incisa leaves. CONCLUSION: This review reports the efforts of the scientific community in authenticating species used in traditional medicine. Moreover, it gives a compendium of phytochemistry and the biological activities of the components from C. incisa leaves.

Environmental photochemistry in Solanum trilobatum mediated plasmonic nanoparticles as a probe for the detection of Cd2+ ions in water.

Nowadays world deals with a lot of environmental troubles out of which water pollution is very dangerous. Water gets contaminated by heavy metal ions is a universal problem which needs suitable consideration to keep up the quality of the water. It will be advantageous that an easy device can be detecting the concentration of heavy metal ions in water. Here, a contaminant, cadmium from industrial affluent into water is considered and focused. Gold nanoparticles (AuNPs) have been synthesized by Solanum trilobatum leaf extract and its applications of antifungal and sensing activity was reported here. The influences of different concentration of these reducing agent on the synthesis of AuNPs (G5 and G10) have been evaluated. The structural, optical, vibrational, morphological and compositional properties of the AuNPs were studied through XRD, UV-vis spectra, FTIR, HRTEM and EDAX analysis. The optical studies showed surface plasmon absorbance peak at 526 nm. It shows that the absorbance of the peak becomes narrow with a higher concentration of leaf extract. XRD results showed the average size of the AuNPs was 8 nm. It also confirmed the high crystallinity of nanoparticles. FTIR exposes that amine and carboxyl groups may be involved in the stabilization and reduction mechanism. TEM pictures of both G10 and G5 demonstrate merely spherical nanoparticles. This morphology control is taken place owing to the adsorbed amine and carboxyl groups onto the gold nanoparticles cap the particles and improve the stability. The presence of gold elements in the sample was identified with the help of EDAX. The sensitivity of the system towards various Cd2+ concentrations was measured as 0.058/mM for G5 and 0.095/mM for G10. The prepared nanoparticles produced highest zone of inhibition (ZOI) of 17.5 mm and 19 mm against human being pathogenic fungi Aspergillus Flavus and Candida albicans respectively. Here, small sized spherical nanoparticles showed good antifungal activity.

Evaluation of cholinesterase inhibitory and antioxidant activity of Wedelia chinensis and isolation of apigenin as an active compound.

BACKGROUND: Wedelia chinensis has been reported as a folk medicine for the treatment of different diseases including neurodegenerative disease. Although the plant has been studied well for diverse biological activities, the effect of this plant in neurological disorder is largely unknown. The present study was undertaken to evaluate the cholinesterase inhibitory and antioxidant potential of W. chinensis. METHODS: The extract and fractions of the plant were evaluated for acetylcholinesterase and butyrylcholinesterase inhibitory activity by modified Ellman method. The antioxidant activity was assessed in several in vitro models/assays such as reducing power, total antioxidant capacity, total phenolic and flavonoid content, scavenging of 2,2'-diphenyl-1-picrylhydrazyl (DPPH) free radical and hydroxyl radical, and inhibition of brain lipid peroxidation. Chromatographic and spectroscopic methods were used to isolate and identify the active compound from the extract. RESULTS: Among the fractions, aqueous fraction (AQF) and ethylacetate fraction (EAF) exhibited high inhibition against acetylcholinesterase (IC50: 40.02 ± 0.16 µg/ml and 57.76 ± 0.37 µg/ml) and butyrylcholinesterase (IC50: 31.79 ± 0.18 µg/ml and 48.41 ± 0.05 µg/ml). Similarly, the EAF and AQF had high content of phenolics and flavonoids and possess strong antioxidant activity in several antioxidant assays including DPPH and hydroxyl radical scavenging, reducing power and total antioxidant activity. They effectively inhibited the peroxidation of brain lipid in vitro with IC50 values of 45.20 ± 0.10 µg/ml and 25.53 ± 0.04 µg/ml, respectively. A significant correlation was observed between total flavonoids and antioxidant and cholinesterase inhibitory activity. Activity guided chromatographic separation led to the isolation of a major active compound from the EAF and its structure was elucidated as apigenin by spectral analysis. CONCLUSIONS: The potential ability of W. chinensis to inhibit the cholinesterase activity and peroxidation of lipids suggest that the plant might be useful for the management of AD.

Tropolone-Bearing Sesquiterpenes from Juniperus chinensis: Structures, Photochemistry and Bioactivity.

The tropolone-bearing sesquiterpenes juniperone A (1) and norjuniperone A (2) were isolated from the folk medicinal plant Juniperus chinensis, and their structures were determined by a combination of spectroscopic and crystallographic methods. Photojuniperones A1 (3) and A2 (4), bearing bicyclo[3,2,0]heptadienones derived from tropolone, were photochemically produced and structurally identified by spectroscopic methods. Predicted by the machine learning-based assay, 1 significantly inhibited the action of tyrosinase. The new compounds also inhibited lipid accumulation and enhanced the extracellular glycerol excretion.

Embelin's Versatile Photochemistry Makes It a Potent Photosensitizer for Photodynamic Therapy.

Embelin, a natural product isolated from Embelia ribes, is a promising small-molecular drug for photodynamic anticancer therapy. Using modern quantum chemical methodology, embelin is shown to possess a versatile photochemistry comprising the capability of singlet oxygen generation, excited-state proton transfer, and oxidation. In particular, the detailed molecular mechanisms of singlet oxygen generation and proton transfer upon excitation are studied in great detail. While excited-state proton transfer can damage the protein itself, it also mediates intersystem crossing along its reaction pathway, thus facilitating singlet oxygen generation. When embelin is bound to proteins, all these processes can lead to protein damage and the desired phototoxicity.

Phytogenic Synthesis of Pd-Ag/rGO Nanostructures Using Stevia Leaf Extract for Photocatalytic H2 Production and Antibacterial Studies.

Continuously increasing energy demand and growing concern about energy resources has attracted much research in the field of clean and sustainable energy sources. In this context, zero-emission fuels are required for energy production to reduce the usage of fossil fuel resources. Here, we present the synthesis of Pd-Ag-decorated reduced graphene oxide (rGO) nanostructures using a green chemical approach with stevia extract for hydrogen production and antibacterial studies under light irradiation. Moreover, bimetallic nanostructures are potentially lime lighted due to their synergetic effect in both scientific and technical aspects. Structural characteristics such as crystal structure and morphological features of the synthesized nanostructures were analyzed using X-ray diffraction and transmission electron microscopy. Analysis of elemental composition and oxidation states was carried out by X-ray photoelectron spectroscopy. Optical characteristics of the biosynthesized nanostructures were obtained by UV-Vis absorption spectroscopy, and Fourier transform infrared spectroscopy was used to investigate possible functional groups that act as reducing and capping agents. The antimicrobial activity of the biosynthesized Pd-Ag-decorated rGO nanostructures was excellent, inactivating 96% of Escherichia coli cells during experiments over 150 min under visible light irradiation. Hence, these biosynthesized Pd-Ag-decorated rGO nanostructures can be utilized for alternative nanomaterial-based drug development in the future.

Light-assisted therapy for biofilm infected micro-arc oxidation TiO2 coating on bone implants.

Implant-associated infections is a main factor leading to the failure of titanium (Ti) implants. Micro-arc oxidation is a convenient and effective technique to form a biocompatible metal (Ag+, Cu2+ and Zn2+) ions-doped TiO2 coatings to combat bacterial infections. However, compared with the sterilization by metal ions, light-triggered antibacterial therapies have accepted more attention due to its higher antibacterial efficiency and security. Although TiO2 is an excellent photocatalyst, it can be triggered by ultraviolet light due to the wide band gap. Herein, molybdenum disulfide (MoS2) modified TiO2 coating was fabricated on Ti by a hybrid process of micro-arc oxidation and hydrothermal treatment. The hybrid coating exhibits excellent antibacterial activity under the irradiation of 808 nm near-infrared light because of the synergistic antibacterial effects of reactive oxygen species and hyperthermia, and Staphylococcus aureus (S. aureus) biofilm can be eradicated within 15 min both in vivo and in vitro. Furthermore, collagen decorated on the surface of the hybrid coating can improve the proliferation, adhesion and spreading of MC3T3-E1 osteoblasts.

MiR-CLIP reveals iso-miR selective regulation in the miR-124 targetome.

Many microRNAs regulate gene expression via atypical mechanisms, which are difficult to discern using native cross-linking methods. To ascertain the scope of non-canonical miRNA targeting, methods are needed that identify all targets of a given miRNA. We designed a new class of miR-CLIP probe, whereby psoralen is conjugated to the 3p arm of a pre-microRNA to capture targetomes of miR-124 and miR-132 in HEK293T cells. Processing of pre-miR-124 yields miR-124 and a 5'-extended isoform, iso-miR-124. Using miR-CLIP, we identified overlapping targetomes from both isoforms. From a set of 16 targets, 13 were differently inhibited at mRNA/protein levels by the isoforms. Moreover, delivery of pre-miR-124 into cells repressed these targets more strongly than individual treatments with miR-124 and iso-miR-124, suggesting that isomirs from one pre-miRNA may function synergistically. By mining the miR-CLIP targetome, we identified nine G-bulged target-sites that are regulated at the protein level by miR-124 but not isomiR-124. Using structural data, we propose a model involving AGO2 helix-7 that suggests why only miR-124 can engage these sites. In summary, access to the miR-124 targetome via miR-CLIP revealed for the first time how heterogeneous processing of miRNAs combined with non-canonical targeting mechanisms expand the regulatory range of a miRNA.

Wavelength-Dependent Photochemistry and Biological Relevance of a Bilirubin Dipyrrinone Subunit.

Phototherapy is a standard treatment for severe neonatal jaundice to remove toxic bilirubin from the blood. Here, the wavelength-dependent photochemistry of vinylneoxanthobilirubic acid methyl ester, a simplified model of a bilirubin dipyrrinone subunit responsible for a lumirubin-like structural rearrangement, was thoroughly investigated by liquid chromatography and mass and absorption spectroscopies, with the application of a multivariate curve resolution analysis method supplemented with quantum chemical calculations. Irradiation of the model chromophore leads to reversible Z → E photoisomerization followed by reversible photocyclization to a seven-membered ring system (formed as a mixture of diastereomers). Both the isomerization processes are efficient (ΦZE ∼ ΦEZ ∼ 0.16) when irradiated in the wavelength range of 360-410 nm, whereas the E-isomer cyclization (Φc = 0.006-0.008) and cycloreversion (Φ-c = 0.002-0.004) reactions are significantly less efficient. The quantum yields of all processes were found to depend strongly on the wavelength of irradiation, especially when lower energy photons were used. Upon irradiation in the tail of the absorption bands (490 nm), both the isomers exhibit more efficient photoisomerization (ΦZE ∼ ΦEZ ∼ 0.30) and cyclization (Φc = ∼0.07). In addition, the isomeric bilirubin dipyrrinone subunits were found to possess important antioxidant activities while being substantially less toxic than bilirubin.

Greener Synthesis of Zinc Oxide Nanoparticles: Characterization and Multifaceted Applications.

Nanoparticles (NPs) have unique properties compared to their bulk counterparts, and they have potentials for various applications in many fields of life science. Green-synthesized NPs have garnered considerable interest due to their inherent features such as rapidity, eco-friendliness and cost-effectiveness. Zinc oxide nanoparticles (ZnO NPs) were synthesized using an aqueous extract of Kalanchoe blossfeldiana as a reducing agent. The resulting nanoparticles were characterized via X-ray diffraction (XRD), dynamic light scattering (DLS), UV-Vis spectroscopy, photoluminescence (PL), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS). The antimicrobial potential of the synthesized ZnO NPs against bacterial and fungal strains was examined by the disk diffusion method, and they showed a promising antibacterial and antifungal potential. The catalytic activity of the synthesized ZnO NPs in reducing methylene blue (MB) and eosin was studied via UV-Vis spectroscopy. The decolorization percentages of the MB and Eosin Y dyes were 84% and 94%, respectively, which indicate an efficient degradation of the ZnO NPs. In addition, the cytotoxic activity of the ZnO NPs on the HeLa cell line was evaluated via in vitro assay. The MTT assay results demonstrate a potent cytotoxic effect of the ZnO NPs against the HeLa cancer cell line.

Optimization of High-Pressure Extraction Process of Antioxidant Compounds from Feteasca regala Leaves Using Response Surface Methodology.

Circular economy principles are based on the use of by-products from one operation as the raw materials in another. The aim of this work is to obtain extracts with high antioxidant capacity and resveratrol content for the superior capitalization of the biomass of Feteasca regala leaves obtained during vineyard horticultural operations in spring. In order to obtain a high-quality extract at an industrial level, an optimal extraction process is needed. Central composite design (CCD) was used for the experiment design, which contained three independent variables: the ratio of extraction solvent to solid matter, temperature (°C) and time (minutes). The evaluation of extracts was done by measuring the total antioxidant capacity of the extracts using photo-chemiluminescent techniques, and the resveratrol content using liquid chromatography. Process optimization was done using response surface methodology (RSM). Minitab software version 17.0 was used for the design of experiments and data analysis. Regression analysis showed that the model predicts 87.5% of the variation for resveratrol and 96% for total antioxidant capacity (TAC). The temperature had the biggest influence on the extraction yield. The optimal operational conditions for the extraction method applied had the following conditions: ratio e/m 2.92; 43.23 °C and 55.4 min. A maximum value of 34,623 µg ascorbic acid equivalent (AAE) /mL total antioxidant capacity and 182.4 µg/mL resveratrol content were obtained when the optimal extraction parameters where used. The values obtained in experiments proved that by using RSM an accurate model can be obtained for extraction of Feteasca regala leaves.

Preclinical study of the medicinal plants for the treatment of malignant melanoma.

Melanoma is the most aggressive type of skin cancer and originates from pigment-containing cells called melanocytes. The incidence of melanoma has been increasing worldwide. In the current study, the cytotoxic and photo-cytotoxic activities of different medicinal plants from Lamiaceae (Salvia cedronella, Salvia chionantha, and Salvia adenophylla), Asteraceae (Klasea kurdica, Klasea bornmuelleri, and Achillea millefolium), Apiaceae (Cuminum cyminum, and Anethum graveolens), and Polygonaceae (Rumex crispus) families were studied against HT 144 (Human malignant melanoma) cancer cell lines. The activities were performed by employing the MTT assay. Moreover, the apoptotic effects of the plant extracts were investigated by flow cytometry with annexin V/PI dual staining technique. The production of intracellular ROS by DCFH-DA technique and the effects of TNF-α secretion on apoptosis were also investigated. All plant extracts exhibited cytotoxic, and photo-cytotoxic effects against HT 144 cancer cells. Salvia species and Klasea species induced apoptosis via intracellular ROS generation secreted by TNF-α. On the other hand, A. millefolium, C. cyminum, A. graveolens, and R. crispus extracts induced apoptosis due to the intracellular generation of ROS, but, via the different pathway. In conclusion, this study indicates that the tested medicinal plant extracts have the potential in the treatment of melanoma.

Observation of Enhanced Dissociative Photochemistry in the Non-Native Nucleobase 2-Thiouracil.

We present the first study to measure the dissociative photochemistry of 2-thiouracil (2-TU), an important nucleobase analogue with applications in molecular biology and pharmacology. Laser photodissociation spectroscopy is applied to the deprotonated and protonated forms of 2-TU, which are produced in the gas-phase using electrospray ionization mass spectrometry. Our results show that the deprotonated form of 2-thiouracil ([2-TU-H]-) decays predominantly by electron ejection and hence concomitant production of the [2-TU-H]· free-radical species, following photoexcitation across the UVA-UVC region. Thiocyanate (SCN-) and a m/z 93 fragment ion are also observed as photodecay products of [2-TU-H]- but at very low intensities. Photoexcitation of protonated 2-thiouracil ([2-TU·H]+) across the same UVA-UVC spectral region produces the m/z 96 cationic fragment as the major photofragment. This ion corresponds to ejection of an HS· radical from the precursor ion and is determined to be a product of direct excited state decay. Fragment ions associated with decay of the hot ground state (i.e., the ions we would expect to observe if 2-thiouracil was behaving like UV-dissipating uracil) are observed as much more minor products. This behaviour is consistent with enhanced intersystem crossing to triplet excited states compared to internal conversion back to the ground state. These are the first experiments to probe the effect of protonation/deprotonation on thionucleobase photochemistry, and hence explore the effect of pH at a molecular level on their photophysical properties.

Surfactant removal from wastewater using photo-cathode microbial fuel cell and laterite-based hybrid treatment system.

Sodium dodecyl sulfate (SDS) is a widely used anionic surfactant, which finds its way to the receiving water body due to the incapability of conventional wastewater treatment systems to completely remove it. A hybrid treatment system consisting of upflow microbial fuel cell (MFC) with titanium dioxide (TiO2) as a photocathode catalyst was developed for treating synthetic wastewater spiked with SDS (10.00 ± 0.46 mg L-1). Effluent from anodic chamber of MFC was passed through raw laterite soil filter followed by the photo-cathodic chamber with TiO2-coated cathode irradiated with the UV spectrum. This hybrid system was operated under varying hydraulic retention time (HRT) in anodic chamber of MFC. The SDS removal efficiency of more than 96% along with organic matter removal efficiency of more than 71% was obtained by this hybrid system at different HRTs. The MFC having cathode coated with TiO2 could generate a maximum power density of 0.73 W m-3 and 0.46 W m-3 at the HRT of 12 h and 8 h, respectively, showing the adverse effect of increased SDS loading rate on the electrical performance of MFC. This investigation highlighted the importance of HRT in anodic chamber of MFC and offered solution for effective removal of surfactant from wastewater.

How the 2010 Deepwater Horizon spill reshaped our understanding of crude oil photochemical weathering at sea: a past, present, and future perspective.

The weathering of crude oil at sea has been researched for nearly half a century. However, there have been relatively few opportunities to validate laboratory-based predictions about the rates, relative importance, and controls of oil weathering processes (e.g., evaporation, photo-oxidation, and emulsification) under natural field conditions. The 2010 Deepwater Horizon (DWH) spill in the Gulf of Mexico provided the oil spill science community with a unique opportunity to evaluate our laboratory-based predictions in nature. With a focus on photochemical weathering, we review what we knew prior to the DWH spill, what we learned from the DWH spill, and what priority gaps in knowledge remain. Three key findings from the DWH spill are discussed. First, the rate and extent of photochemical weathering was much greater for the floating surface oil than expected based on early conceptual models of oil weathering. Second, indirect photochemical processes played a major role in the partial oxidation of the floating surface oil. Third, the extensive and rapid changes to the physical and chemical properties of oil by sunlight may influence oil fate, transport, and the selection of response tools. This review also highlights findings and predictions about photochemical weathering of oil from several decades ago that appear to have escaped the broader scientific narrative and ultimately proved true for the DWH spill. By focusing on these early predictions and synthesizing the numerous findings from the DWH spill, we expect this review will better prepare the oil spill science community to respond to the next big spill in the ocean.

Controllable growth of Au nanostructures onto MoS2 nanosheets for dual-modal imaging and photothermal-radiation combined therapy.

Multifunctional theranostic nanoagents are attractive to realize comprehensive imaging and effective treatment of tumours. Herein, a novel strategy is developed to controllably guide the epitaxial growth of gold nanostructures onto MoS2 nanosheets. The as-prepared MoS2-Au nanostructures (MA) manifest an enhanced near-infrared (NIR) absorbance with strong photostability. After modification, the obtained MA-PEG shows strong X-ray attenuation and photothermal conversion ability, promising for CT and photoacoustic imaging with an enhanced intensity in tumours. Moreover, in vivo photothermal and radiation therapy with MA-PEG achieves synergistic tumour treatment efficiency through hyperthermia elevated oxygenation level and sensitized radiation therapy. This work illustrates the development of a unique MA nanostructure with enhanced NIR absorbance and strong photoelectric absorbance as a multifunctional theranostic agent with great potential for dual-modal imaging-guided photothermal-radiation therapy of cancer.