Design Of A Novel Apparatus To Enrich Analytes Via A Diffuse-Evaporation Process For HPLC-FTIR Analysis

Mixed sample analysis is applied to various aspects.HPLC can be a good separation method to separate mixed samples.However,many substances have no absorption peaks in the UV-Vis spectra region,so that the HPLC cannot give a certain result in the qualitative analysis.Since most organic compounds have their unique absorption peaks in the IR region,IR spectroscopy can be used as a good method for identification.Therefore,HPLC-IR can be used as a good separation and analysis method.The mixture could be separated by high performance liquid chromatography,and the sample was detected on the IR spectrometer.HPLC-IR has been lacking suitable interfaces.The literature has been reported that the germanium can be used as the interface,but the solvent cannot be volatile timely after collected from HPLC,so that the IR absorbance is particularly low and some IR fingerprint area peak cannot be observed.Therefore,this experiment tries to design a kind of interface to keep the sample area from spreading while it can concentrate the effluent.A novel apparatus using CuO powder as the interface of HPLC-FTIR analysis is reported.After improvement,a device which similar to a funnel was finally determined.The device can be used to store the effluent of HPLC,in which the solvent in the effluent is continuously volatile,so that the solute is enriched in the surface.When choosing the range of the matrix,we should choose from the transition metal oxide,which is generally selected with oxides such as CuO and Ni O.The system used in this experiment did not have strong acidic substance,and copper oxide was used as the substrate after consideration.CuO has the following advantages:1.CuO is transparent in the 4000 cm~-11 to 1000 cm~-11 IR region;2.Methanol,ethanol and water can be completely removed on the surface of copper oxide.The sample size of the device is about 200?m,which can be applied to the probe of the micro-IR spectrometer.The feasibility of the new device was verified by using benzamide and SDBS as an example.