产品介绍 液体样品自动进样、静态顶空自动进样、大体积顶空进样、自动固相微萃取、自动液-液萃取、在线样品衍生、热解析和直接热解析。支持以下气相： Agilent5890/6890/6850 Thermo Trace2000/GC8000top Varian GC/3400/3600/3800/3900 Shimadzu GC14/17/2010 PE Autosystem XL/Clarus 500 支持以下色谱工作站： Agilent Chemstation DataApex Clarity Dionex Chromeleon EZChrom E lite/Ezstart Justice Software Shromperfect Leco Chrom TOF Shimadzu GC/GCMSsolution Shimadzu Class VP Therom ChromQuest Therom Xcalibur Varian Star/Galaxie Waters Masslynx XYZ进样方式 模块化设计 大体积进样技术无样品定量环 可按需要制 高效率的样品进样无传输管道 各模块更换便捷 与主流GC/GC-MS 无切换阀 系统无缝兼容 Solid phase microextraction, or SPME, is a sample preparation technique used both in the laboratory and on-site. Developed in the early 1990s at the University of Waterloo by Dr. Pawliszyn's group, it is a simple and inexpensive technique where the use of solvents is not necessary. SPME can be thought of as a very short gas chromatography column turned inside out. SPME involves the use of a fiber coated with an extracting phase, that can be a liquid (polymer) or a solid (sorbent), which extracts different kinds of analytes (including both volatile and non-volatile) from different kinds of media, that can be in liquid or gas phase. The quantity of analyte extracted by the fiber is proportional to its concentration in the sample so long as equilibrium is reached or, in case of short time pre-equilibrium, with help of convection or agitation. After extraction, the SPME fiber is transferred to the injection port of separating instruments, such as a Gas Chromatograph, where desorption of the analyte takes place and analysis is carried out. The attraction of SPME is that the extraction is fast and simple and can be done without solvents, and detection limits can reach parts per trillion (ppt) levels for certain compounds. SPME also has great potential for field applications; on-site sampling can be done even by nonscientists without the need to have a GC-MS at each location. When properly stored, samples can be analyzed days later in the laboratory without significant loss of volatiles. Solid phase microextraction is a fast, solvent less alternative to conventional sample extraction techniques. In SPME, analytes establish equilibria among the sample matrix, the headspace above the sample, and a polymer-coated fused fiber, then are desorbed from the fiber to a chromatography column. Because analytes are concentrated on the fiber, and are rapidly delivered to the column, minimum detection limits are improved and resolution is maintained. SPME is compatible with analyte separation/detection by gas chromatography or HPLC, and provides linear results for wide concentrations of analytes. SPME is an equilibrium process based upon Fick’s 1st law of diffusion SPME is a technique where the sample is incubated or agitated to equilibrate the headspace. A SPME fiber is then introduced to the headspace for a predetermined period of time. The SPME fiber is then transferred to a hot GC injection port. Analytes that were adsorbed to the fiber from the sample headspace are desorbed directly in the GC inlet. SPME fibers are a distributed by Supleco and are available in a wide variety of polarities. By matching fiber polarity with target analyte characteristics, the analysis can be optimized for improved sensitivity and performance. SPME
extraction for heated and agitated samples
SPME offers some important advantages:
Comparison of SPME to SPESPE exhaustively extracts all of the analytes, but they are diluted during elution 1mL of sample containing 1µg/mL of analyte passed through tube, eluted with 1mL of solvent = 1µg/mL X 1µl injection = 1ng (Concentrating to 100µl or injecting 10µl = 10ng on column SPME partially extracts analytes but desorbs the
entire amount 1mL sample containing 1µg/mL of analyte extracted with fiber. 1%
goes on fiber. 0.01 x 1µg = 10ng desorbed on column |
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