Preparation and in vivo imaging of a novel potential αvβ3 targeting PET/MRI dual-modal imaging agent

Journal of Radioanalytical and Nuclear Chemistry - Multi-modal biomedical imaging has played an essential role in tumor diagnosis. However, constructing a multi-modal imaging contrast agent with...     

Gibberellin Increases the Bud Yield and Theanine Accumulation in Camellia sinensis (L.) Kuntze

Tea (Camellia sinensis) is one of the most important cash crops in the world. Theanine, as an important amino acid component in tea, is a key quality index for excellent tea quality and high economic value. People increase theanine accumulation in tea mainly through the application of nitrogen fertilizer, shading and pruning. However, these methods are not effective. In this study, we treated tea buds with a 100 μM solution of GA₃ containing 1‰ tween-20, investigated the effects of GA₃ on theanine accumulation, bud yield, chlorophyll fluorescence parameters and expression level of theanine biosynthesis pathway genes in tea plant by qPCR, LC-MS/MS etc. Results showed that change trends of theanine and GA₃ was extremely positively correlated with each other. Exogenous GA₃ upregulated the expression level of theanine biosynthesis pathway genes, caused an increase of theanine content (mg·g^-1) by 27% in tea leaves compared with Mock, and accelerated the germination of buds and elongation of shoots, which lead to a significant increase of tea yield by 56% (w/w). Moreover, the decrease of chlorophyll contents, photochemical quenching coefficient (qP) and relative electron transport rate (rETR) under GA₃ treatment suggested that GA₃ reduced photosynthesis in the tender tea leaves, indicating that the decline of carbon assimilation in tea plants was conducive to the nitrogen metabolism, and it was beneficial to the accumulation of theanine. This study provided a new technical and theoretical support for the precise control of tea quality components and phenophase.     

Optimizing Adsorption of 17α-Ethinylestradiol from Water by Magnetic MXene Using Response Surface Methodology and Adsorption Kinetics,Isotherm, and Thermodynamics Studies

Magnetic MXene composite Fe₃O₄@Ti₃C₂ was successfully prepared and employed as 17α-ethinylestradiol (EE2) adsorbent from water solution. The response surface methodology was employed to investigate the interactive effects of adsorption parameters (adsorption time, pH of the solution, initial concentration, and the adsorbent dose) and optimize these parameters for obtaining maximum adsorption efficiency of EE2. The significance of independent variables and their interactions were tested by the analysis of variance (ANOVA) and t-test statistics. Optimization of the process variables for maximum adsorption of EE2 by Fe₃O₄@Ti₃C₂ was performed using the quadratic model. The model predicted maximum adsorption of 97.08% under the optimum conditions of the independent variables (adsorption time 6.7 h, pH of the solution 6.4, initial EE2 concentration 0.98 mg L⁻¹, and the adsorbent dose 88.9 mg L⁻¹) was very close to the experimental value (95.34%). pH showed the highest level of significance with the percent contribution (63.86%) as compared to other factors. The interactive influences of pH and initial concentration on EE2 adsorption efficiency were significant (p < 0.05). The goodness of fit of the model was checked by the coefficient of determination (R²) between the experimental and predicted values of the response variable. The response surface methodology successfully reflects the impact of various factors and optimized the process variables for EE2 adsorption. The kinetic adsorption data for EE2 fitted well with a pseudo-second-order model, while the equilibrium data followed Langmuir isotherms. Thermodynamic analysis indicated that the adsorption was a spontaneous and endothermic process. Therefore, Fe₃O₄@Ti₃C₂ composite present the outstanding capacity to be employed in the remediation of EE2 contaminated wastewaters.     

Pressurized liquid extraction of ginger (Zingiber officinale Roscoe) with bioethanol: an efficient and sustainable approach

To develop an efficient green extraction approach for recovery of bioactive compounds from natural plants, we examined the potential of pressurized liquid extraction (PLE) of ginger (Zingiber officinale Roscoe) with bioethanol/water as solvents. The advantages of PLE over other extraction approaches, in addition to reduced time/solvent cost, the extract of PLE showed a distinct constituent profile from that of Soxhlet extraction, with significantly improved recovery of diarylheptanoids, etc. Among the pure solvents tested for PLE, bioethanol yield the highest efficiency for recovering most constituents of gingerol-related compounds; while for a broad concentration spectrum of ethanol aqueous solutions, 70% ethanol gave the best performance in terms of yield of total extract, complete constituent profile and recovery of most gingerol-related components. PLE with 70% bioethanol operated at 1500 psi and 100 °C for 20 min (static extraction time: 5 min) is recommended as optimized extraction conditions, achieving 106.8%, 109.3% and 108.0% yield of [6]-, [8]- and [10]-gingerol relative to the yield of corresponding constituent obtained by 8h Soxhlet extraction (absolute ethanol as extraction solvent).     

四价锕系离子U(Ⅳ)和Th(Ⅳ)与肾上腺素配合物的研究

本文采用电位滴定法和电子光谱法研究了肾上腺素及它与U(Ⅳ)和Th(Ⅳ)的溶液化学,探讨了各体系的平衡机理、配合物的组成、性质和稳定性.在t=25℃,I=0.10mol/1(KNO_3),氩气气氛中测得肾上腺素的各微观解离常数为:pk_1=8.74,pk_2=9.34,pk_(12)=9.80,pk_(21)=9.20;采用非线性最小二乘法BETA程序在CDC·CYBER170/825计算机上求得肾上腺素的宏观解离常数为pk_1~d=8.71,pk_2~d=9.83,pk_3~d=13.0和各配合物的形成常数为:lgβ_(UHL)=35.99,lgβ_(UL)=20.58,lgβ_(UH_2L_2)=45.17,lgβ_(UHL_2)=40.51,lgβ_(UL_2)=37.32;lgβ_(ThHL)=20.04,lgβ_(ThHL)=17.28,lgβ_(ThH_2L_2)=41.58,lgβ_(ThHL_2)=37.96,lgβ_(ThL_2)=32.49.