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Sample Preparation Methodology for Environmental and Pharmaceutical Analysis

Author: JiaXiaoYan
Tutor: LuoHongQun
School: Southwestern University
Course: Environmental Science
Keywords: Sample pre-treatment Inverting DLLME Ionic liquids Environmental analysis Pharmaceutical Analysis
CLC: X502
Type: Master's thesis
Year: 2010
Downloads: 330
Quote: 0
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Abstract

The sample pre-treatment is extracted from the sample matrix in the pre-analysis, separation, enrichment of the target compound, is the longest time spent in the sample analysis process, the labor intensity maximum process, and will greatly affect the accuracy and precision of the method . Hence, sample preparation has become a bottleneck in the entire analysis process. In the environment and drugs, in particular medicine analysis, the sample matrix is ??complex, the low concentration of the target analyte; in the sample processing are simultaneously extracted and the eluted matrix compound may enhance or inhibit the analysis signal. Therefore, it is essential to establish the appropriate sample pretreatment methods. In recent years, the sample pre-treatment technology toward miniaturization, automation, high throughput, on-line coupled with the rapid economic development of environmental friendly direction. The ionic liquid used in DLLME process, improve the extraction efficiency, recovery, reduce the use of organic solvents, the extraction process more environmentally friendly; while inverting DLLME method to solve the traditional dispersion and three sample pretreatment method has been successfully used in flavonoids, triterpenoids and phenolic phase microextraction only processing samples in aqueous solution and can not deal with the limitations of the organic solvent in the sample, and to expand the scope of application of the DLLME method; Determination of substances, five experimental system. The main contents are as follows: 1. Ultrasonic extraction RP-HPLC simultaneous determination of the compound Houttuynia Tablets Morin and quercetin ultrasonic extraction and determination of compound Houttuynia film Morin and quercetin RP-HPLC. Using only cross-test, optimize the optimum conditions of the the ultrasonic extraction compound Houttuynia tablets Morin and quercetin. At 40 ~ 45 ℃, 50% ethanol extract liquid ratio 1:20 (g / mL), ultrasound 10 mmin repetitive processing times. Column Shim-PackVP-ODS column (150 × 4.6 mm, 5 μm); mobile phase was methanol -0.3% phosphoric acid (50:50); flow rate of 0.7 mL / min; 260 nm at detection. Morin linear range 0.8 ~ 100.0μg/mL, r = 0.9998. The linear range Hupi cable for 1.5 ~ 50.0μg/mL, r = 0.9993. The method is simple, rapid, accurate and suitable for the compound of Houttuynia film Morin and quercetin separation and determination. DLLME ionic liquid-based high-performance liquid chromatography determination of phenols in the Jialing River water samples ionic liquids for DLLME extraction of the Jialing water samples 2,4 - dichlorophenol 2,4,6 - trichlorophenol, bisphenol A, 4 - nonylphenol, 4 - octylphenol. 1.0mL acetone (dispersing agent) which contains 111μL1-hexyl-3-methylimidazolium hexafluorophosphate (extractant) in 5.0 mL of the sample solution was added, after shaking to form an opacifying system. After centrifugation 1 - hexyl-3-methylimidazolium hexafluoro phosphate deposition to the bottom of the tube, Pipette 20μL determined directly using micro-injector. And some important parameters, such as the proportion of ionic liquid type, the type of dispersant, ionic liquid, and a dispersant, salt effect and pH were optimized. Five analyte in the range of 0.01 ~ 1.0μg/mL good linearity (r = 0.9967-0.9993), the method recoveries between 95.3 to 111.3%. Ionic liquid-based DLLME method has the advantages of simple, rapid, low-cost, high recovery and enrichment effect. Ultrasonic extraction - reverse DLLME HPLC determination of oleanolic acid in Ligustrum establishment of a new micro-extraction technology - reverse DLLME. By orthogonal test, and optimize the ultrasonic extraction conditions. Add 7.0 mL of water was added in 3.0 mL of the sample solution 200μL chloroform, after shaking, opacifying system consisting of an ethanol / water / chloroform is formed at this point. After centrifugation, chloroform deposited onto the bottom of the tube with a tiny injector Pipette 20μL determined directly. And some important parameters such as the type and volume of the extraction agent, the volume of water, extraction time is optimized. The method in the range 10-200μg/mL showing a good linear relationship (r = 0.9997), the recoveries were 98.0-108.5%. Reverse DLLME is a very simple, fast and efficient method of extraction and enrichment of oleanolic acid from Ligustrum lucidum samples. 4 ultrasonic extraction - ionic liquids powerful loquat capsule ursolic acid ionic liquid is used for strong loquat capsule ursolic acid reverse DLLME DLLME High Performance Liquid Chromatography. The ended cross experiments designed to optimize the ultrasound-assisted extraction of experimental conditions. 100μl ionic liquid was added in a 1.5 mL sample solution added 2.5 mL of an acidic aqueous solution (pH 2.0), after shaking to form an opacifying system. After centrifugation, the ionic liquid is deposited on the bottom of the tube, Pipette 20μL determined directly using micro-injector. Performance is based on ionic liquid reverse DLLME described by RP-HPLC determination of ursolic acid in strong loquat capsule. The method in the range 2.0-60.0μg/mL showing a good linear relationship (r = 0.9989), the recoveries were 95.9-105.5%. Ultrasonic extraction - ionic liquid the DLLME HPLC method for the determination of ursolic acid and oleanolic acid jacaranda using ionic liquid-based reverse DLLME method of separation and determination of the blue Jacaranda ursolic acid and oleanolic acid. The ended cross experiments designed to optimize the ultrasound-assisted extraction of experimental conditions. 4.0 mL sample solution to add 200μL ionic liquid shake after adding 9.0 mL of water to form an emulsion system. After centrifugation, the ionic liquid is deposited on the bottom of the tube, Pipette 20μL determined directly using micro-injector. And factors that may affect the efficiency of extraction, such as the volume of the ionic liquids of the type and volume of water, and extraction time were optimized. Ursolic acid concentration within 14.0-50.0μg/mL the 4.0-50.0μg/mL and oleanolic acid concentration showed a good linear relationship, r of 0.9999 and 0.9996, respectively, and the recovery was 83.4. 9-106.2% and 98.3 to 101.4%. The method is simple, rapid, cost-effective, high recovery rate.

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