Establishment of Indirect Competitive Enzyme-linked Immunosorbent Assay (ic-ELISA) for Copper ion (Cu) in Raw Meat Products.

Adding an appropriate amount of copper to feed can promote the growth and development of livestock; however, a large amount of heavy metal copper can accumulate in livestock through the enrichment effect, which poses a serious threat to human health. Traditional Cu detection relies heavily on complex and expensive instruments, such as inductively coupled plasma-optical emission spectrometry (ICP-OES) and inductively coupled plasma-mass spectrometry (ICP-MS); thus, convenient and simple rapid detection technologies are urgently needed. In this paper, synthesized copper antigens were used to immunize mice and highly specific anticopper monoclonal antibodies were obtained, which were verified to exhibit high affinity and specificity.

Application of an improved hollow fiber liquid phase microextraction technique coupled to LC-MS/MS to studying migration of fluorescent whitening agents from plastic food contact materials.

In this paper, a new hollow fiber liquid-phase microextraction method was developed to improve the extraction of five fluorescent whitening agents that migrated from plastics food contact materials. Influencing factors, such as the types of membrane, the extraction solvent, the stirring speed, the addition of salt ion, and extraction time, were investigated in detail. Under the optimal conditions, high enrichment factors (71-205) can be obtained with 15 μL extraction solvent.

Tracing Geographical Origins of Teas Based on FT-NIR Spectroscopy: Introduction of Model Updating and Imbalanced Data Handling Approaches.

This work presents a reliable approach to trace teas' geographical origins despite changes in teas caused by different harvest years. A total of 1447 tea samples collected from various areas in 2014 (660 samples) and 2015 (787 samples) were detected by FT-NIR. Seven classifiers trained on the 2014 dataset all succeeded to trace origins of samples collected in 2014; however, they all failed to predict origins for the 2015 samples due to different data distributions and imbalanced dataset.

Stable Isotope Ratio and Elemental Profile Combined with Support Vector Machine for Provenance Discrimination of Oolong Tea (Wuyi-Rock Tea).

This paper focused on an effective method to discriminate the geographical origin of Wuyi-Rock tea by the stable isotope ratio (SIR) and metallic element profiling (MEP) combined with support vector machine (SVM) analysis. Wuyi-Rock tea ( = 99) collected from nine producing areas and non-Wuyi-Rock tea ( = 33) from eleven nonproducing areas were analysed for SIR and MEP by established methods. The SVM model based on coupled data produced the best prediction accuracy (0.

Rapid discrimination of the geographical origins of an oolong tea (anxi-tieguanyin) by near-infrared spectroscopy and partial least squares discriminant analysis.

This paper focuses on a rapid and nondestructive way to discriminate the geographical origin of Anxi-Tieguanyin tea by near-infrared (NIR) spectroscopy and chemometrics. 450 representative samples were collected from Anxi County, the original producing area of Tieguanyin tea, and another 120 Tieguanyin samples with similar appearance were collected from unprotected producing areas in China. All these samples were measured by NIR.

Combining electronic tongue array and chemometrics for discriminating the specific geographical origins of green tea.

The feasibility of electronic tongue and multivariate analysis was investigated for discriminating the specific geographical origins of a Chinese green tea with Protected Designation of Origin (PDO). 155 Longjing tea samples from three subareas were collected and analyzed by an electronic tongue array of 7 sensors. To remove the influence of abnormal measurements and samples, robust principal component analysis (ROBPCA) was used to detect outliers in each class.

Automatic and rapid discrimination of cotton genotypes by near infrared spectroscopy and chemometrics.

This paper reports the application of near infrared (NIR) spectroscopy and pattern recognition methods to rapid and automatic discrimination of the genotypes (parent, transgenic, and parent-transgenic hybrid) of cotton plants. Diffuse reflectance NIR spectra of representative cotton seeds (n = 120) and leaves (n = 123) were measured in the range of 4000-12000 cm(-1). A practical problem when developing classification models is the degradation and even breakdown of models caused by outliers.

4,5,6,7-Tetra-chloro-N-(2-fluoro-phen-yl)phthalimide.

In the title compound, C(14)H(4)Cl(4)FNO(2), the benzene ring and the phthalimide plane are nearly planar, the maximum deviations being 0.005 (2) and 0.010 (2) Å, respectively, but the mol-ecule as a whole is not planar: the dihedral angle between the two planar ring systems is 68.

N-(2,3,4-Trifluoro-phen-yl)phthalimide.

In the title compound, C(14)H(6)F(3)NO(2), the benzene ring and the phthalimide ring system make a dihedral angle of 60.12 (7)°. Weak inter-molecular C-H⋯O and C-H⋯F hydrogen bonds are present in the crystal structure.

N-(3,4-Difluoro-phen-yl)phthalimide.

In the title compound, C(14)H(7)F(2)NO(2), the phthalimide ring system is nearly planar [maximum atomic deviation = 0.028 (1) Å] and it is twisted with respect to the attached benzene ring, making a dihedral angle of 55.70 (6)°.

2-(2,2,2-Trifluoro-eth-yl)isoindoline-1,3-dione.

In the title compound, C(10)H(6)F(3)NO(2), the isoindole ring system is planar, the maximum atomic deviation being 0.012 (2) Å. The C-C bond of the trifluoro-ethyl group is twisted with respect to the isoindole ring by a dihedral angle of 62.

4,5,6,7-Tetra-chloro-2-(4-fluoro-phen-yl)isoindoline-1,3-dione.

The title compound, C(14)H(4)Cl(4)FNO(2), has crystallographic twofold symmetry with the N and F atoms and two C atoms of the benzene ring located on a twofold rotation axis. The isoindole-dione ring system is almost planar [maximum atomic deviation = 0.036 (3) Å], and is twisted with respect to the florobenzene ring, making a dihedral angle of 58.

4,5,6,7-Tetra-chloro-2-(2,2,2-trifluoro-eth-yl)isoindoline-1,3-dione.

In the title compound, C(10)H(2)Cl(4)F(3)NO(2), the isoindoline ring system is almostplanar, the maximum atomic deviation being 0.064 (2) Å. The C-C bond of the ethyl-ene group is twisted with respect to the isoindoline plane by a dihedral angle of 59.