ABSTRACT
Objective To establish the solid phase extraction (SPE) with GC/MS technology for fish poi-soning cases to determine five pesticides in fishpond. Methods By three solid phase extraction column including Oasis HLB cartridge, Bond Elut C18 and SampliQ C18, the recovery rate was compared to ex-tract and purify five pesticides in fishpond. The effects of different kinds and dosages of eluents on ex-tract rate were also reviewed. Results Using Bond Elut C18 as solid phase extraction column and 3 mL benzene as eluent, the linear range of mass concentration of five pesticides in fishpond was 1-50 μg/mL, and the correlation coefficient was 0.996 2-0.999 6. The limit of detection was 3.4-26 μg/L and the re-covery was 61.49%-102.48%. The relative standard deviations was less than or equal to 3.01%. Conclu-sion With high sensitivity, good accuracy and precision, SPE -GC/MS has simple and quick operation and less solvent. It can be applied to determination of five pesticides in fishpond.
ABSTRACT
Objective To develop the accelerated solvent extraction (ASE ) for determ ining pesticides pre-sent in blood sam ples. Methods Pesticides were extracted by ASE with optimized param eters to study recovery rate affected by extraction tem perature, time and agent. GC/MS was used to perform quantita-tive analysis.Results The recovery rates of eight pesticides were 70.6%-92.4%. The coefficient of variation was less than 5.0%. Agood linear relationship was obtained at the concentration range of 0.5-5.0μg/m L . Conclusion The m ethod was fast and sim ple with high recovery rate and good repeatability. It can be applied to analyze pesticides present in the blood specimen.
ABSTRACT
We studied the effects of three inorganic carbon sources, Na2CO3, NaHCO3 and CO2, and their initial concentrations on lipid production of Chlorella vulgaris. Chlorella vulgaris could utilize Na2CO3, NaHCO3 and CO2 to produce lipids. After 10-day cultivation with each of the three inorganic carbon sources, lipid yield of Chlorella vulgaris reached its peak with the concentration increase of the inorganic carbon source, but dropped again by further increase of the concentration. The pH value of the culture medium for Chlorella vulgaris increased after the cultivation on inorganic carbon source. The optimal concentration of both Na2CO3 and NaHCO3 was 40 mmol/L, and their corresponding biomass dry weight was 0.52 g/L and 0.67 g/L with their corresponding lipid yield 0.19 g/L and 0.22 g/L. When the concentration of CO2 was 6%, Chlorella vulgaris grew the fastest and its biomass dry weight was 2.42 g/L with the highest lipid yield of 0.72 g/L. When the concentration of CO2 was too low, the supply of inorganic carbon was insufficient and lipid yield was low. A too high concentration of CO2 caused a low pH and lipid accumulation was inhibited. Na2CO3 and NaHCO3 were more favorable for Chlorella vulgaris to accumulate unsaturated fatty acids than that of CO2.
Subject(s)
Biofuels , Carbon , Metabolism , Carbon Dioxide , Pharmacology , Carbonates , Pharmacology , Chlorella vulgaris , Metabolism , Culture Media , Culture Techniques , Methods , Lipids , Sodium Bicarbonate , PharmacologyABSTRACT
AIM To investigate the effects of trifluoperazine on naloxone precipitated withdrawal symptoms in morphine dependent rats and mice, and its pharmacological mechanisms. METHODS\ Naloxone precipitated tests in morphine dependent rats and mice were used. RESULTS\ Trifluoperazine(2～20 mg?kg -1 ) dose dependently inhibited naloxone precipitated withdrawal jumping, wet dog shakes, paw tremor and weight loss in morphine dependent mice. With ip trifluoperazine (5～20 mg?kg -1 ), most of positive withdrawal symptoms, including jumping, wet dog shakes, defeacation, weight loss, teeth chattering, salivation, diarrhea, ptosis and irritating, induced by naloxone in morphine dependent rats were significantly reduced. Apomorphine (2～8 mg?kg -1 ), a mixed DA 1/DA 2 receptor agonist, did not affect inhibition of trifluoperazine on naloxone precipitated withdrawal symptoms in morphine dependent mice. However, nifedipine(5～20 mg?kg -1 ), a L type voltage sensitive calcium channel blocker, enhanced a pharmacological action of trifluoperazine against naloxone precipitated symptoms in morphine dependent mice. CONCLUSION\ Trifluoperazine attenuates naloxone precipitated withdrawal symptoms in morphine dependent rats and mice by inhibiting the activity of post receptor calmodulin, but it does not antagonizes DA 2 receptor, in central nervous system.