ABSTRACT
Qualitative and quantitative methods were used to establish the quality of different medicinal parts of Poria cocos (Poriae Cutis, rubra Poria, white Poria, Poria cum Radix Pini) by using ultra-performance convergence chromatography coupled with photo-diode array and quadrupole time-of-flight mass spectrometry (UPC2-PDA-Q-TOF/MSE). A total of 18 chromatographic peaks were detected from Poria cocos by UPC2-PDA. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to compare the four medicinal parts. The results showed that there were significant differences in the components of different medicinal parts, and the main triterpenoic acids were poricoic acid A, poricoic acid B, dehydroeburicoic acid, and dehydrotrametenolic acid. When combined with the common active component polyporenic acid C, a method for determination of five triterpenoic acids in different parts of Poria cocos was established. These components could be separated within 15 min, and the amount of methanol was 3.63% of that of HPLC method. Taking the five triterpenoid acids as an index, the content of triterpenoid acids in different parts of Poria cocos from high to low were Poriae Cutis, rubra Poria, white Poria and Poria cum Radix Pini. The method is simple, rapid, and uses minimal solvent. The mobile phase of environment-friendly gas carbon dioxide has unique advantages in reducing environmental pollution, which can provide a basis for the development and standard formulation of Poria cocos and its related products.
ABSTRACT
Gas chromatography (GC) is mainly used to detect the levels of short-chain fatty acids (SCFAs), but with the deepening of research,the drawbacks of GC have become more and more obvious in the fields of food,chemical engineering and clinical application. The analysis on existing research results showed that ultra performance convergence chromatography (UPC2) was appropriate for the analysis of lipid metabolism. The UPC2 is a new kind of chromatographic separation technology developed in recent five years and the level of SCFAs is associated with the research on multiple diseases. Therefore,application of UPC2 in the detection of SCFAs would be helpful for the scholars at home and abroad to carry out deeper researches,and also helpful to guide the treatment for various metabolic disorders. In this paper,the researches on SCFAs in recent ten years were reviewed; the shortcomings of GC and liquid chromatography (LC) in the detection of SCFAs were reviewed; the development process,basic characteristics and research status of UPC2 at home and abroad were introduced; feasibility and innovation of UPC2 in the detection of SCFAs were summarized. Pretreatment methods for UPC2 application to the detection of SCFAs in feces or serum were collected; the problems that should be noticed during the process of sample pretreatment were pointed out; meanwhile, an research outlook on methodology of UPC2 application in the detection of SCFAs was conducted. The effects of extracting solvent,mobile phase,and auxiliaryt solvent on chromatographic behavior as well as the physicochemical property, type and choice of UPC2 chromatographic column were mainly discussed in this paper. In addition, the choices of basic modifier,acid modifier,and salinity modifier were briefly outlined, in order to provide efficient,simple,environmental,and economic detection technologies for the research on SCFAs, and provide better reference solutions for the rapid detection of massive clinical samples.
ABSTRACT
Abstract A chiral separation and residue determination method for cis-epoxiconazole enantiomers in apple, grape and tea samples was developed and validated by ultra performance convergence chromatography combined with quadrupole time-of-flight mass spectrometry ( UPC2-QTOF/MS) . The Chrial CCA column was used to separate cis-epoxiconazole enantiomers and the chromatography conditions ( mobile phase modifier and proportion, column temperature, automated backpressure regulator, and auxiliary solvent ) were optimized. Samples were extracted by acetonitrile, and respectively purified by Cleanert TPT or Pesti-Carb solid phase extraction ( SPE ) columns, then analyzed by UPC2-QTOF/MS. The optimum conditions were as follows:mobile phase was CO2/isopropanol (95: 5, V/V), flow-rate was 2. 0 mL/min, automated backpressure regulator (ABPR) was 13. 79 MPa, column temperature was 30℃, with a post-column mauxiliary solvent of methanol/water (1:1, V/V) containing 2 mmol/L ammonium formate. The analyte was quantified by matrix external standard method. The results showed that linear range of this method was 0. 01-1. 00 mg/L, and the correlation coefficients were above 0 . 99 . The recoveries of cis-epoxiconazole enantiomers at three spiked levels (0. 005, 0. 025 and 0. 25 mg/kg) in fruit matrix were 67. 9%-92. 8% with relative standard deviations (RSDs, n=6) less than 10%, and the limit of quantification (LOQ) of enantiomers was 0. 005 mg/kg. The recoveries of cis-epoxiconazole enantiomers at three spiked levels (0. 01, 0. 05 and 0. 5 mg/kg) in black tea were 74 . 1% -84 . 0% with RSDs ( n=6 ) less than 8%, and the LOQ for these two enantiomers was 0. 01 mg/kg. This method is rapid, convenient and reliable, and could meet the requirement of residue analysis.
ABSTRACT
A new method for chiral separation and purity inspection of landiolol hydrochloride and its stereoisomers was developed by ultra-performance convergence chromatography ( UPC2 ) . The mobile phase was the mixture of supercritical CO2 and methanol/n-butyl alcohol/acetonitrile (1:1:1, V/V) plus 0. 5%NH3?H2O. The separation was carried out on the Daicel CHIRALPAK? IF column (150 mm × 4. 6 mm, 3 μm) with a flow rate of 2. 8 mL/min at 50℃ using 223 nm as detection wavelength. Under the optimized experimental conditions, for R,R-stereoisomer, R,S-stereoisomer and S,R-stereoisomer, the detection limits (LOD, S/N=3) were 0. 3, 0. 4 and 0. 3 mg/L, the linear ranges were 2-300 mg/L, 5-300 mg/L and 2-300 mg/L, the recoveries of spike samples were 103. 4%±2. 5%, 91. 8%±2. 5% and 101. 7%±1. 5%, and the injection repeatabilities were 0. 06%, 0. 09% and 0. 08% (n=6), respectively. The experimental results demonstrate that the UPC2-based method can be used for the analysis and determination of landiolol hydrochloride and its stereoisomers.
ABSTRACT
An ultra performance convergence chromatographic ( UPC2 ) method was established for the attribution analysis of the main peaks as well as the quantitative determination of echinacoside andβ-ecdyserone in Bushen Jiannao Grains. The samples were extracted with ethanol and separated on Waters ACQUITY UPC2TM BEH column (100 mm × 3. 00 mm, 1. 7 μm), with a gradient supercritical CO2-0. 05%phosphoric acid-methanol solvent system at 40 ℃. The flow rate was 0. 8 mL/min, the detection wavelength was set at 248 nm and the injection volume was 1 μL. Results showed that all the main peaks in the fingerprint were clearly attributed. The peak named 12 wasβ-ecdyserone with the content of 380μg/g and the peak named 15 was echinacoside with the content of 9. 562 mg/g. The method was simple, eco-friendly, accurate and reliable compared with HPLC and UPLC.
ABSTRACT
A rapid method was developed for the determination of 5 common fatty acids, palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid in industrial oleic acid based on ultra_performance convergence chromatography_mass spectrometry ( UPC_MS) . The sample was dissolved by n_hexane, followed by clean_up of extract using 0. 22 μm organic phase filter. The fatty acids were separated in 3 min on the column of Acquity UPC2 BEH 2_EP by gradient elution with carbon dioxide and methanol/acetonitrile (1∶1, V/V) system, and finally detected by MS detector in ESI- mode. Through the optimization of UPC2_MS condition, the reasonable linearity was achieved for all the analytes over the range of 0. 5-100 mg/L with the correlation coefficients ( R2 ) greater than 0. 9985. The recoveries for five fatty acids at three spiked levels were in the range from 89 . 3% to 106 . 67% with relative standard deviations of 0 . 8%-3 . 0%. The limits of detection for target compounds in the method ranged from 0. 07 mg/L to 0. 26 mg/L. The real sample analysis showed that this method was simple,fast and had a good separation effect. There was no need of derivatization for fatty acid samples. This work would provide a fast and effective detection method for UPC2 technology in oil related research field.
ABSTRACT
A new method was developed for the determination of 11 fat_soluble vitamins ( A, D, E and K) and its derivatives in vitamin tablets by ultra performance convergence chromatography ( UPC2 ) . The mobile phase was the mixture of supercritical CO2 and acetonitrile at a flow rate of 1 mL/min. The separation was carried out on the Waters Acquity UPC2 HSS C18 SB 100 mm × 3. 0 mm i. d. , 1. 8 μm column. The UV detector was set at a wavelength of 284 nm. The limits of detection ( LOD) were 1. 5-2. 0 mg/L, and the calibration linear for VK1 , VK2 , VK3 and VB3 was 3-300 mg/L, linear for VA, VA palmitate, VA formic acid, VE, VE acetate, VD2 and VD3 was 5-300 mg/L, respectively. Its spiked recoveries were 97. 31%-98. 76%, and the relative standard deviations ( RSDs) were 0. 41%-0. 96%. The method is applicable for the determination of fat_soluble vitamins ( A, D, E and K) and Their derivatives in vitamin tablets.
ABSTRACT
A method was developed for the determination of bifenthrin in tea by ultra performance convergence chromatography ( UPC2 ) . The samples were extracted with petroleum ether and cleaned up with Waters Sep-Pak:Carbon NH2 , and then detected by UPC2 . The mobile phase was the mixture of supercritical CO2 and acetonitrile at a flow rate of 1. 5 mL/min. The separation was conducted on a column of ACQUITY UPC2 TM BEH (100 mmí3. 0 mm,1. 7 μm). The UV detector was set at a wavelength of 220 nm. The detection limit was 20 μg/L. The linear range of bifenthrin was 0. 32-10. 30 mg/L. The recoveries ranged from 88. 7% to 98. 2%. The relative standard deviations (RSD) were from 1. 4% to 2. 8%. The result showed that the UPC2 was more efficient, rapid and low-cost than GC-MS. The method can meet the testing requirements of bifenthrin in tea. The efficacy of UPC2 on testing the concentration of bifenthrin in tea was compared with GC-MS based on National Proficiency Testing and the results were satisfactory.