Serum PCDD/F levels in metropolitan populations living near a municipal solid waste incinerator in Eastern China.

Ambient exposure to polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) is suspected to cause adverse human health outcomes. Herein, serum samples from 40 residents in the neighborhood of a municipal solid waste incinerator (MSWI) in the metropolitan area were measured for PCDD/Fs. The mean toxic equivalent (TEQ) concentration of total PCDD/Fs in human serum samples was 16.8 pg TEQ/g lipid. Serum PCDD/F levels were significantly higher in residents adjacent to the MSWI than in those from areas far from the emission source (p < 0.01). In addition, there were no significant associations between serum PCDD/Fs levels and factors, such as gender, age, and BMI in donors. For non-occupationally exposed populations, OCDD and 1,2,3,7,8-PeCDD in serum are available as indicators of total PCDD/Fs and total TEQ, respectively. The atmospheric PCDD/Fs levels were within a relatively low range in areas upwind and downwind of the MSWI. The results of the principal component analysis showed a distinct difference in PCDD/F congener patterns between air and serum samples, suggesting inhalation exposure could have a limited influence on the human body burden. Our findings will deepen the current knowledge of endogenous PCDD/F exposure in urban populations, and also facilitate public health protection strategies near MSWIs.

Determination of tropane alkaloids by heart cutting reversed phase - Strong cation exchange two dimensional liquid chromatography.

Current Chinese Pharmacopoeia (ChP) standards apply liquid extraction combined with one dimensional liquid chromatography (1DLC) method for determining alkaloids in herbal medicines. The complex pretreatments lead to a low analytical efficiency and possible component loss. In this study, a heart cutting reversed phase - strong cation exchange two dimensional liquid chromatography (RP - SCX 2DLC) approach was optimized for simultaneously quantifying tropane alkaloids (anisodine, scopolamine and hyoscyamine) in herbal medicines and herbal medicine tablets without further treatment of the filtered extract. The chromatographic conditions were systematically optimized in terms of column type, mobile phase composition and flow rate. To improve peak capacity and obtain symmetric peak shape of alkaloids, a polar group embedded C18 column combined with chaotropic salts was used in the first dimension. To remove the disturbance of non-alkaloids, achieve unique selectivity and acquire symmetric peak shape of alkaloids, an SCX column combined with phosphate buffer was used in the second dimension. Method validation was performed in terms of linearity, precision (0.54-0.82%), recovery (94.1-105.2%), limit of detection (LOD) and limit of quantification (LOQ) of the three analytes varied between 0.067-0.115mgL-1 and 0.195-0.268mgL-1, respectively. The method demonstrated superiority over 1DLC method in respect of resolution (less alkaloid co-eluted), sample preparation (no pretreatment procedure) and transfer rate (minimum component loss). The optimized RP - SCX 2DLC approach was subsequently applied to quantify target alkaloids in five herbal medicines and herbal medicine tablets from three different manufactures. The results demonstrated that the developed heart cutting RP - SCX 2DLC approach represented a new, strategically significant methodology for the quality evaluation of tropane alkaloid in related herbal medicines that involve complex chemical matrix.

A non-derivative method for the quantitative analysis of isosteroidal alkaloids from Fritillaria by high performance liquid chromatography combined with charged aerosol detection.

A non-derivative method was developed for the qualitative and quantitative analysis of isosteroidal alkaloids from Fritillaria thunbergii. During method development the performance of two universal detectors, the charged aerosol detector (CAD) and evaporative light scattering detector (ELSD), were evaluated. The CAD was found to be 30 to 55 times more sensitive than ELSD enabling the measurement of low levels of reference compound impurities that could not be detected by ELSD. The peak area percent of the reference compound, peimisine, obtained by CAD was 50.10%, but 91.66% by ELSD showing that CAD is suitable to estimate the presence of impurities. The CAD showed good reproducibility with overall intra- and inter-day peak area RSD values of less than 1.8% and 2.7%, respectively and had a linear dynamic range of up to 4 orders of magnitude (0.06-44mg/L) for peimine and peiminine. The optimized method was used for the quantitative analysis of peimine and peiminine from F. thunbergii.

[Rapid determination of four components in Guizhi Fuling capsule with online two-dimensional liquid chromatography].

To establish the online two-dimensional liquid chromatography by using double gradient liquid chromatography system and UV detector, in order to simultaneously determine the content of paeoniflorin, paenol, amygdaloside and cinnamic acid. A pump of the two-dimensional liquid chromatography was adopted as the one-dimensional separation pump. C18 (3.0 mm x 150 mm, 3 microm) was used as the analytical column, with acetonitrile as the organic phase and 0.08% phosphoric acid + 0.08% triethylamine as the aqueous phase for gradient elution at the flow rate of 0.5 mL x min(-1). Another pump of the two-dimensional liquid chromatography was adopted as the two-dimensional separation pump. PAII C18 was used as the analytical column, with acetonitrile as the organic phase and 20 mmol, pH 3.0 monopotassium phosphate as the aqueous phase for gradient elution at the flow rate of 0.8 mL x min(-1). The detection wavelengths were set at 218, 230, 275 nm by using wavelength time-switching program. The linearity range of paeoniflorin, amygdaloside, paeonol and cinnamic acid were 5.55-222 (r = 0.999 7), 6.6-264 (r = 0.999 8), 3.3-132 (r = 0.999 5) and 0.315-12.6 mg x L(-1) (r = 0.999 7), respectively. The average recoveries of the four components were between 96.12% and 103.9%. The experiment proved that this method was so rapid and accurate in determination results that it could be used for evaluating drug quality.