ABSTRACT
In this paper, MPDA@hydroxyapatite nanocomposites (MPHA NCs) were prepared and applied to develop a novel reactive oxygen species (ROS)-triggered nitric oxide (NO)-enhanced photothermal therapy nanocomposite system composed of indocyanine green (ICG)/L-arginine-MPDA@HAp (AI-MPHA NCs) for displaying both NO gas therapy and photothermal osteosarcoma treatment. The nanosystem exhibited a mesoporous and core-shell structure and high ICG loading efficiency (about 90%). Under near infrared (NIR) irradiation, the AI-MPHA NCs could not only produce heat but also generate reactive oxygen species (ROS), inducing the catalysis of L-Arg to obtain NO. Under NIR irradiation, the AI-MPHA NCs achieved osteosarcoma ablation by a synergistic combination of photothermal therapy and NO-gas therapy. Additionally, the cell viability of MG-63 cells decreased to 23.6% (co-incubated with AI-MPHA NCs) under irradiation with a power density at 1.0 W cm-2 for 10 min. The study proposed a novel nano-platform for NO-enhanced photothermal therapy of osteosarcoma.
Subject(s)
Durapatite/chemistry , Indoles/chemistry , Nanocomposites/chemistry , Nitric Oxide/metabolism , Polymers/chemistry , Reactive Oxygen Species/metabolism , Arginine/chemistry , Bone Neoplasms/drug therapy , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Catalysis , Cell Line, Tumor , Cell Survival/drug effects , Humans , Indocyanine Green/chemistry , Infrared Rays , Nanocomposites/therapeutic use , Nanocomposites/toxicity , Osteosarcoma/drug therapy , Osteosarcoma/metabolism , Osteosarcoma/pathology , Phototherapy/methods , PorosityABSTRACT
With the purpose of guaranteeing the safe use of spirotetramat and preventing its potential health threats to consumers, a QuEChERS extraction method coupled with LC triple-quadrupole tandem MS was applied in this study to determine residual spirotetramat metabolites in different tissues of amaranth (Amaranthus tricolor) and in soil. The results indicate that the spirotetramat degraded into different types of metabolites that were located in different tissues of amaranth and in soil. B-keto, B-glu, and B-enol were the three most representative degradation products in the leaf of amaranth, and B-glu and B-enol were the two major degradation products found in the stem of amaranth; however, only B-enol was detected in the root of amaranth. B-keto and B-mono were the two products detected in the soil in which the amaranth grew. The cytotoxicity results demonstrate that spirotetramat and its metabolite B-enol inhibited cellular growth, and the toxicity of spirotetramat and its metabolite B-enol exceeded than that of the metabolites B-keto, B-mono, and B-glu. This investigation is of great significance to the safe use of spirotetramat in agriculture.
Subject(s)
Aza Compounds/analysis , Chromatography, Liquid/methods , Insecticides/analysis , Spiro Compounds/analysis , Tandem Mass Spectrometry/methods , Amaranthus/chemistry , Amaranthus/metabolism , Animals , Aza Compounds/isolation & purification , Aza Compounds/metabolism , Aza Compounds/toxicity , Cell Line , Cell Proliferation/drug effects , Insecticides/isolation & purification , Insecticides/metabolism , Insecticides/toxicity , Limit of Detection , Plant Leaves/chemistry , Plant Leaves/metabolism , Plant Roots/chemistry , Plant Roots/metabolism , Plant Stems/chemistry , Plant Stems/metabolism , Soil/chemistry , Spiro Compounds/isolation & purification , Spiro Compounds/metabolism , Spiro Compounds/toxicity , Spodoptera/drug effectsABSTRACT
Nowadays, there is an urgent need for the investigation of the field dissipation and assessment of the preharvest interval for trichlorfon residues on rice. To protect consumers from potential health risks, this study can provide references for the safe application of trichlorfon in the rice fields. Results of the field dissipation study showed that the dissipation dynamic equations of trichlorfon were based on the first-order reaction dynamic equations and that the dissipation rates vary among rice plant, brown rice, rice bran, soil, and water. The 2-year field trials conducted in Yangzhou and Xiaogan suggested the interval of each application for trichlorfon on rice to be at least 7 days when 80 % trichlorfon SP was sprayed with a dose ranges between 80 and 160 a.i g/667 m(2). Additionally, the preharvest interval of the last application should be at least 15 days to ensure the amounts of residues below the maximum residue limits of trichlorfon on brown rice (0.1 mg/kg).
