• Journal of fish pathology
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• v.22 no.2
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• pp.125-135
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• 2009

The pharmacokinetic properties of oxolinic acid (OA) were studied after oral administration, intraperitoneal injection and dipping to cultured olive flounder, Paralichthys olivaceus (average 90 g, $23{\pm}1{^{\circ}C}$). Plasma samples were taken at 3, 5, 10, 15, 24, 30, 48, 96 and 144 h post-dose. In oral dosage at 15, 30 and 60 ㎎/㎏, the peak plasma concentrations of OA, which attained at 10~15 h post-dose, were 1.92, 2.45 and 3.72 $\mu{g}/m\ell$, respectively. In intraperitoneal injection with 10 and 20 ㎎/㎏, the peak plasma concentrations of OA, which attained at 10 h post-dose, were 4.1 and 4.8 $\mu{g}/m\ell$, respectively. In dipping in 30 and 50 ppm for 1 h, peak concentrations were observed at 5 h and 30 h post-dose, were 0.22 and 0.38 $\mu{g}/m\ell$, respectively. The kinetic profile of absorption, distribution and elimination of OA in plasma were analyzed fitting to a one-compartment model by WinNonlin program. Calculated parameters for a single oral dosage of 15, 30 and 60 ㎎/㎏, respectively, were: AUC (the area under the concentration-time curve)=70.93, 120.0 and 141.86 $\mu{g}$ $h/m\ell$ $T_{max}$ (time for maximum concentration)=16.22, 20.39 and 17.33 h; $C_{max}$ (maximum concentration)=���D1.61, 2.40 and 3.01 $\mu{g}/m\ell$. Following intraperitoneal injection of 10 and 20 ㎎/㎏, these parameters were AUC=184.7 and 315.92 $\mu{g}$ $h/m\ell$ $T_{max}$=5.91 and 6.26 h; $C_{max}$=4.19 and 4.45 $\mu{g}/m\ell$. Following dipping at 30 and 50 ppm, these parameters were AUC=17.58 and 21.69 $\mu{g}$ $h/m\ell$ $T_{max}$=19.08 and 31.43 h; $C_{max}$x=0.22 and 0.25 $\mu{g}/m\ell$.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.5
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• pp.399-407
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• 2009

Laser induced breakdown spectroscopy(LIBS) is an simple analysis method for directly quantifying many kinds of soil micro-elements on site using a small size of laser without pre-treatment at any property of materials(solid, liquid and gas). The purpose of this study were to find an optimum condition of the LIBS measurement including wavelengths for quantifying soil elements, to relate spectral properties to the concentration of soil elements using LIBS as a simultaneous un-breakdown quantitative analysis technology, which can be applied for the safety assessment of agricultural products and precision agriculture, and to compare the results with a standardized chemical analysis method. Soil samples classified as fine-silty, mixed, thermic Typic Hapludalf(Memphis series) from grassland and uplands in Tennessee, USA were collected, crushed, and prepared for further analysis or LIBS measurement. The samples were measured using LIBS ranged from 200 to 600 nm(0.03 nm interval) with a Nd:YAG laser at 532 nm, with a beam energy of 25 mJ per pulse, a pulse width of 5 ns, and a repetition rate of 10 Hz. The optimum wavelength(${\lambda}nm$) of LIBS for estimating soil and plant elements were 308.2 nm for Al, 428.3 nm for Ca, 247.8 nm for T-C, 438.3 nm for Fe, 766.5 nm for K, 85.2 nm for Mg, 330.2 nm for Na, 213.6 nm for P, 180.7 nm for S, 288.2 nm for Si, and 351.9 nm for Ti, respectively. Coefficients of determination($r^2$) of calibration curve using standard reference soil samples for each element from LIBS measurement were ranged from 0.863 to 0.977. In comparison with ICP-AES(Inductively coupled plasma atomic emission spectroscopy) measurement, measurement error in terms of relative standard error were calculated. Silicon dioxide(SiO2) concentration estimated from two methods showed good agreement with -3.5% of relative standard error. The relative standard errors for the other elements were high. It implies that the prediction accuracy is low which might be caused by matrix effect such as particle size and constituent of soils. It is necessary to enhance the measurement and prediction accuracy of LIBS by improving pretreatment process, standard reference soil samples, and measurement method for a reliable quantification method.

• Journal of Marine Life Science
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• v.9 no.1
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• pp.9-21
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• 2024

Paralytic shellfish poisoning (PSP) including Saxitoxin (STX) is caused by harmful algae, and poisoning occurs when the contaminated seafood is consumed. The mouse bioassay (MBA), a standard test method for detecting PSP, is being sanctioned in many countries due to its low detection limit and the animal concerns. An alternative to the MBA is the Neuro-2a cell-based assay. This study aimed to establish various test conditions for Neuro-2a assay, including cell density, culture conditions, and STX treatment conditions, to suit the domestic laboratory environment. As a result, the initial cell density was set to 40,000 cells/well and the incubation time to 24 hours. Additionally, the concentration of Ouabain and Veratridine (O/V) was set to 500/50 μM, at which most cells died. In this study, we identified eight concentrations of STX, ranging from 368 to 47,056 fg/μl, which produced an S-shaped dose-response curve when treated with O/V. Through inter-laboratory variability comparison of the Neuro-2a assay, we established five Quality Control Criteria to verify the appropriateness of the experiments and six Data Criteria (Top and Bottom OD, EC₅₀, EC₂₀, Hill slop, and R² of graph) to determine the reliability of the experimental data. The Neuro-2a assay conducted under the established conditions showed an EC₅₀ value of approximately 1,800~3,500 fg/μl. The intra- & inter-lab variability comparison results showed that the coefficients of variation (CVs) for the Quality Control and Data values ranged from 1.98% to 29.15%, confirming the reproducibility of the experiments. This study presented Quality Control Criteria and Data Criteria to assess the appropriateness of the experiments and confirmed the excellent repeatability and reproducibility of the Neuro-2a assay. To apply the Neuro-2a assay as an alternative method for detecting PSP in domestic seafood, it is essential to establish a toxin extraction method from seafood and toxin quantification methods, and perform correlation analysis with MBA and instrumental analysis methods.