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New Primary Standards for Establishing SI Traceability for Moisture Measurements in Solid Materials
Heinonen, M.,Bell, S.,Choi, B. Il,Cortellessa, G.,Fernicola, V.,Georgin, E.,Hudoklin, D.,Ionescu, G. V.,Ismail, N.,Keawprasert, T.,Krasheninina, M.,Aro, R.,Nielsen, J.,Oğ,uz Aytekin, S.,Ö,ste Springer-Verlag 2018 International journal of thermophysics Vol.39 No.1
Chung, Hyung Suk,Lee, Young-Jun,Rahman, Md. Musfiqur,Abd El-Aty, A.M.,Lee, Han Sol,Kabir, Md. Humayun,Kim, Sung Woo,Park, Byung-Jun,Kim, Jang-Eok,Hacımü,ftü,oğ,lu, Fazil,Nahar, Nilufar,Sh Elsevier BV 2017 Science of the Total Environment Vol.605 No.-
<P><B>Abstract</B></P> <P>Veterinary antibiotics are available for uptake by the plants through sources such as manure, irrigation, and atmospheric interaction. The present study was conducted to estimate the half-lives of three veterinary antibiotics, chlortetracycline (CTC), enrofloxacin (ENR), and sulphathiazole (STZ), in soil and experimentally explore their uptake from contaminated soil to radish roots and leaves. Samples were extracted using a modified citrate-buffered version of the quick, easy, cheap, effective, rugged, and safe “QuEChERS” method followed by liquid chromatography coupled with tandem mass spectrometric analysis (LC–MS/MS) in the positive ion mode. Good linearity was observed for the three tested antibiotics in soil and plants (roots and leaves) with high coefficients of determination (<I>R</I> <SUP>2</SUP> ≥0.9922). The average recovery rates at two spiking levels with three replicates per level ranged between 77.1 and 114.8%, with a relative standard deviation (RSD)≤19.9% for all tested drugs. In a batch incubation experiment (<I>in vitro</I> study), the half-lives of CTC, ENR, and STZ ranged from 2.0–6.1, 2.2–4.5, and 1.1–2.2days, respectively. Under greenhouse conditions, the half-lives of the three target antibiotics in soil with and without radishes were 2.5–6.9 and 2.7–7.4; 4.7–16.7 and 10.3–14.6; and 4.4–4.9 and 2.5–2.8days, respectively. Trace amounts of the target antibiotics (CTC, ENR, and STZ) were taken up from soil <I>via</I> roots and entered the leaves of radishes. The concentration of CTC was lower than 2.73%, ENR was 0.08–3.90%, and <1.64% STZ was uptaken. In conclusion, the concentrations of the tested antibiotics decreased with time and consequently lower residues were observed in the radishes. The rapid degradation of the tested antibiotics in the present study might have only little impact on soil microorganisms, fauna, and plants.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A method to estimate the half-life of veterinary antibiotics in soil was developed. </LI> <LI> Veterinary antibiotic uptake rate by radish from contaminated soil was determined. </LI> <LI> The half-lives of antibiotics in soil with and without radishes did not differ. </LI> <LI> Trace antibiotic residue levels moved to roots and leaves from contaminated soil. </LI> <LI> We elucidate residual antibiotic transplantation and antibiotic tolerance in soil. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Rahman, Md. Musfiqur,Abd El-Aty, A.M.,Kabir, Md. Humayun,Chung, Hyung Suk,Lee, Han Sol,Hacımü,ftü,oğ,lu, Fazil,Jeong, Ji Hoon,Chang, Byung-Joon,Shin, Ho-Chul,Shim, Jae-Han Elsevier 2018 Food chemistry Vol.239 No.-
<P><B>Abstract</B></P> <P>A simple and effective method was developed for analyzing dinotefuran and its three metabolites (MNG, UF, and DN) in plum using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Due to the polarity and high water miscibility, dinotefuran and some of its metabolites (especially DN) have some limitations to be extracted with acetonitrile and salt following the “QuEChERS” sample preparation methodology. Alternatively, the samples were extracted with methanol, and purified with dispersive-solid phase extraction procedure (d-SPE) using primary secondary amine (PSA) and C<SUB>18</SUB> sorbents after filtration, and mass up. Due to the suppression effect originated from plum matrix, matrix-matched calibration curves, which provided good linearity with coefficient of determination (<I>R<SUP>2</SUP> </I>)≥0.998, were used for quantification of all analytes. Blank plum samples fortified with 2 spiking levels (10×LOQ and 50×LOQ) yielded satisfactory recoveries for all tested analytes in the range of 83.01 to 110.18% with relative standard deviation (RSD)≤8.91. The method was successfully applied to field-incurred plum samples and dinotefuran and all metabolites were positively detected and quantified. In conclusion, we suggest that the method can be expanded to polar compounds having solvent and partitioning problems in any of the versions of QuEChERS.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A simultaneous method was developed for dinotefuran and its highly polar metabolites in plum. </LI> <LI> Mass-up was introduced instead of salting out for exact quantitation. </LI> <LI> Internal standard is not needed for the newly developed methodology. </LI> <LI> The method can be used either as it is or with slight modification in other matrices. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Jeon, Jong-Sup,Kim, Han-Taek,Kim, Myeong-Gil,Oh, Moon-Seog,Hong, Se-Ra,Yoon, Mi-Hye,Shin, Ho-Chul,Shim, Jae-Han,Afifi, Nehal Aly,Hacımü,ftü,oğ,lu, Ahmet,Abd El-Aty, A. M. Springer-Verlag 2016 Chromatographia Vol.79 No.13
<P>A simultaneous analytical method was developed and validated to quantify three lipophilic compounds; namely glabridin (an isoflavonoid isolated from crude licorice), (-)-alpha-bisabolol (a sesquiterpene alcohol obtained from plant extracts), and ascorbyl tetraisopalmitate (a fat-soluble molecule derived from vitamin C) in functional cosmetic cream using high-performance liquid chromatography (HPLC) coupled with photodiode array detection (PAD). Cosmetic cream samples were extracted with a mixture of acetonitrile and isopropyl alcohol (45:55, v/v) and the target compounds were separated on a C-18 column with a gradient mobile phase consisting of deionized water, acetonitrile, and isopropyl alcohol. The detector wavelengths were 228, 202, and 221 nm, for glabridin, (-)-alpha-bisabolol, and ascorbyl tetraisopalmitate, respectively. The calibration curves showed good linearity with determination coefficients (R (2)) a parts per thousand yen 0.999. The mean recoveries were ranged between 89.8 and 103.9 % with relative standard deviations (RSDs) < 5 %. The intra- and inter-day precision was < 2 %. The limits of detection (LODs) were 0.03, 0.4, and 4.02 mu g mL(-1) for glabridin, (-)-alpha-bisabolol, and ascorbyl tetraisopalmitate, respectively. The method was successfully applied for monitoring 11 market samples, in which glabridin was quantified in the range of 17.5-25 mg 100 g(-1), (-)-alpha-bisabolol in the range of 25.1-677 mg 100 g(-1), and 140.6-291.5 mg 100 g(-1) for ascorbyl tetraisopalmitate. The proposed analytical method is simple, sensitive, and versatile and can be used for the quantification of lipophilic compounds in cosmetics in a single chromatographic run.</P>