Chromatographic method was invented about 80 years ago.Since thengreat development has been made and it is now widely used as an analyti-cal tool in chemistry,biology,medicine and environmental sciences.Since 1970,hig...Chromatographic method was invented about 80 years ago.Since thengreat development has been made and it is now widely used as an analyti-cal tool in chemistry,biology,medicine and environmental sciences.Since 1970,highly precise HPLC(high performance liquid chromatography)pumps,various kinds of columns and high sensitive detectors have beenmanufactured.The computerizing equipment can implement the automaticanalysis under optimal conditions and provide more precise and convenientdata acquisition and processing.The HPLC technique has become moreand more important for the biologists and medical scientists in展开更多
Native glycopeptides are suitable to FAB mass spectrometric analysis due to their high polarity, low volatility and large molecular size. The deficiency in the FAB spectra of glycopeptides is the limited number o...Native glycopeptides are suitable to FAB mass spectrometric analysis due to their high polarity, low volatility and large molecular size. The deficiency in the FAB spectra of glycopeptides is the limited number of peaks and the low abundances of fragments. In order to obtain the information of carbohydrate sequence the permethylation of carbohydrate, a well known method, is recommended here. The L β aspartamido carbohydrate from chicken egg albumin was chosen as the model compound of glycopeptides. Our experiments showed obvious carbohydrate sequence in the spectra of permethylated aspartamido carbohydrates. The key conditions to perform the method are the methylation reagent and purification process for the permethylated derivatives.展开更多
ABSTRACT A quantitative method for the assay of free cholesterol has been described in this paper. The experimental conditions for the determination of cholesterol in serum by Thin-layer chromatography were disscused....ABSTRACT A quantitative method for the assay of free cholesterol has been described in this paper. The experimental conditions for the determination of cholesterol in serum by Thin-layer chromatography were disscused. The solvent System was petroleum ether-ethyl acetate-glacial acetic acid (8o:20:1) and the spra-ying reagent was a solution of sulphuric acid and vanillin. Under the selected con-ditions, the peak area was linearly related to the cholesterol amount for the range between 80～700 ng per spot. The intraplate and interplate coefficients were 2.4% and 7.4% respectively. The recovery of cholesterol was 101.6%. The method presented was simple, rapid and accurate. The results of experi-mental investigation and clinical application were satisfactory.展开更多
A high-performance liquid chromatography was describ-ed to measure the concentration of human 3-methylhistidine in urine witho-phthaldialdehyde pre-column derivatization.This assay system resultedin a clear separation...A high-performance liquid chromatography was describ-ed to measure the concentration of human 3-methylhistidine in urine witho-phthaldialdehyde pre-column derivatization.This assay system resultedin a clear separation of 3-methylhistidine derivative from other derivativ-es in urine within 25 min.Linearity,recovery and coefficients of vari-ation were studied.The method has been successfully applied to routineanalysis for clinical studies and diagnosis.展开更多
Halogenated natural products(HNPs)are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known.Therefore,several persistent and bioaccumulative HNP groups,together w...Halogenated natural products(HNPs)are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known.Therefore,several persistent and bioaccumulative HNP groups,together with manmade polychlorinated biphenyls(PCBs)and polybrominated diphenyl ethers(PBDEs),were quantified in the blubber of nine sperm whales(Physeter macrocephalus)stranded on the coast of the Mediterranean Sea in Italy.The naturally occurring polybrominated hexahydroxanthene derivatives(PBHDs;sum of TetraBHD and TriBHD)were the most prominent substance class with up to 77,000 ng/g blubber.The mean PBHD content(35,800 ng/g blubber)even exceeded the one of PCBs(28,400 ng/g blubber),although the region is known to be highly contaminated with manmade contaminants.Based on mean values,Q1∼PBDEs>MeO-BDEs∼2,2′-diMeO-BB 80 and several other HNPs followed with decreasing amounts.All blubber samples contained an abundant compound whose molecular formula(C_(16)H_(19)Br_(3)O_(2))was verified using high-resolution mass spectrometry.The only plausible matching isomer was(2S,4′S,9R,9′S)-2,7-dibromo-4′-bromomethyl-1,1-dimethyl-2,3,4,4′,9,9′-9,9′-hexahydro-1H-xanthen-9-ol(OH-TriBHD),a hydroxylated secondary metabolite previously detected together with TriBHD and TetraBHD in a sponge known to be a natural producer of PBHDs.The estimated mean amount of the presumed OH-TriBHD was 3000 ng/g blubber,which is unexpectedly high for hydroxylated compounds in the lipids of marine mammals.展开更多
Background:Chinese Danggui(Angelica sinensis)and Japanese Danggui(Angelica acutiloba)are evaluated as the same in using and critical of quality control in Vietnamese Pharmacopoeia.In Vietnam,Japanese Danggui were accl...Background:Chinese Danggui(Angelica sinensis)and Japanese Danggui(Angelica acutiloba)are evaluated as the same in using and critical of quality control in Vietnamese Pharmacopoeia.In Vietnam,Japanese Danggui were acclimatized and cultivated in several regions in recent years.Despite the huge climatic difference between Vietnam and Japan,Japanese Danggui grows very well in Vietnam.However,there are no studies to assess the overall quality of this medicinal herbs.Aims and Objectives:The aim of this study is to develop a method to identify and assay simultaneously 5 component compounds of these crude herbs:chlorogenic acid,ferulic acid,scopoletin,xanthotoxin and ligustilide by high-performance liquid chromatography with photodiode array detector(HPLC-PDA).Materials and Methods:The procedure was optimized by using column Phenomenex Gemini 5μm PR C18,15 x 4,6 mm with the detection wavelength set at 321 nm for detector PDA and mobile phase was composed of(A)ACN and(B)aqueous solution 1%of acid acetic using a gradient elution.Analytes were performed at 30°C with a flow rate of 1.0 mL/min.Results:The developped method were fully validated for linearity,accuracy,recovery and met the validation requirements,proved practical applicability for the quality control of these herbs and related products.Conclusion:The method was successfully applied to the quantification of five markers simultaneously from collected samples.展开更多
文摘Chromatographic method was invented about 80 years ago.Since thengreat development has been made and it is now widely used as an analyti-cal tool in chemistry,biology,medicine and environmental sciences.Since 1970,highly precise HPLC(high performance liquid chromatography)pumps,various kinds of columns and high sensitive detectors have beenmanufactured.The computerizing equipment can implement the automaticanalysis under optimal conditions and provide more precise and convenientdata acquisition and processing.The HPLC technique has become moreand more important for the biologists and medical scientists in
文摘Native glycopeptides are suitable to FAB mass spectrometric analysis due to their high polarity, low volatility and large molecular size. The deficiency in the FAB spectra of glycopeptides is the limited number of peaks and the low abundances of fragments. In order to obtain the information of carbohydrate sequence the permethylation of carbohydrate, a well known method, is recommended here. The L β aspartamido carbohydrate from chicken egg albumin was chosen as the model compound of glycopeptides. Our experiments showed obvious carbohydrate sequence in the spectra of permethylated aspartamido carbohydrates. The key conditions to perform the method are the methylation reagent and purification process for the permethylated derivatives.
文摘ABSTRACT A quantitative method for the assay of free cholesterol has been described in this paper. The experimental conditions for the determination of cholesterol in serum by Thin-layer chromatography were disscused. The solvent System was petroleum ether-ethyl acetate-glacial acetic acid (8o:20:1) and the spra-ying reagent was a solution of sulphuric acid and vanillin. Under the selected con-ditions, the peak area was linearly related to the cholesterol amount for the range between 80～700 ng per spot. The intraplate and interplate coefficients were 2.4% and 7.4% respectively. The recovery of cholesterol was 101.6%. The method presented was simple, rapid and accurate. The results of experi-mental investigation and clinical application were satisfactory.
文摘A high-performance liquid chromatography was describ-ed to measure the concentration of human 3-methylhistidine in urine witho-phthaldialdehyde pre-column derivatization.This assay system resultedin a clear separation of 3-methylhistidine derivative from other derivativ-es in urine within 25 min.Linearity,recovery and coefficients of vari-ation were studied.The method has been successfully applied to routineanalysis for clinical studies and diagnosis.
文摘Halogenated natural products(HNPs)are considered to be emerging contaminants whose environmental distribution and fate are only incompletely known.Therefore,several persistent and bioaccumulative HNP groups,together with manmade polychlorinated biphenyls(PCBs)and polybrominated diphenyl ethers(PBDEs),were quantified in the blubber of nine sperm whales(Physeter macrocephalus)stranded on the coast of the Mediterranean Sea in Italy.The naturally occurring polybrominated hexahydroxanthene derivatives(PBHDs;sum of TetraBHD and TriBHD)were the most prominent substance class with up to 77,000 ng/g blubber.The mean PBHD content(35,800 ng/g blubber)even exceeded the one of PCBs(28,400 ng/g blubber),although the region is known to be highly contaminated with manmade contaminants.Based on mean values,Q1∼PBDEs>MeO-BDEs∼2,2′-diMeO-BB 80 and several other HNPs followed with decreasing amounts.All blubber samples contained an abundant compound whose molecular formula(C_(16)H_(19)Br_(3)O_(2))was verified using high-resolution mass spectrometry.The only plausible matching isomer was(2S,4′S,9R,9′S)-2,7-dibromo-4′-bromomethyl-1,1-dimethyl-2,3,4,4′,9,9′-9,9′-hexahydro-1H-xanthen-9-ol(OH-TriBHD),a hydroxylated secondary metabolite previously detected together with TriBHD and TetraBHD in a sponge known to be a natural producer of PBHDs.The estimated mean amount of the presumed OH-TriBHD was 3000 ng/g blubber,which is unexpectedly high for hydroxylated compounds in the lipids of marine mammals.
文摘Background:Chinese Danggui(Angelica sinensis)and Japanese Danggui(Angelica acutiloba)are evaluated as the same in using and critical of quality control in Vietnamese Pharmacopoeia.In Vietnam,Japanese Danggui were acclimatized and cultivated in several regions in recent years.Despite the huge climatic difference between Vietnam and Japan,Japanese Danggui grows very well in Vietnam.However,there are no studies to assess the overall quality of this medicinal herbs.Aims and Objectives:The aim of this study is to develop a method to identify and assay simultaneously 5 component compounds of these crude herbs:chlorogenic acid,ferulic acid,scopoletin,xanthotoxin and ligustilide by high-performance liquid chromatography with photodiode array detector(HPLC-PDA).Materials and Methods:The procedure was optimized by using column Phenomenex Gemini 5μm PR C18,15 x 4,6 mm with the detection wavelength set at 321 nm for detector PDA and mobile phase was composed of(A)ACN and(B)aqueous solution 1%of acid acetic using a gradient elution.Analytes were performed at 30°C with a flow rate of 1.0 mL/min.Results:The developped method were fully validated for linearity,accuracy,recovery and met the validation requirements,proved practical applicability for the quality control of these herbs and related products.Conclusion:The method was successfully applied to the quantification of five markers simultaneously from collected samples.
