Preparation Of Amino Acid Ionic Liquids And Its Application In Spectral Analysis

With the gradual expansion of the types and applications of functionalized ionic liquids,the environmental toxicity and bio-affinity has been criticized.The use of biological molecules such as amino acids as a functional ionic liquid part will effectively improve the environment and biological compatibility.At present,amino acid ionic liquids have been widely used in separation and enrichment,chromatographic modification,and chiral enantiomeric recognition.This paper mainly explores the application of amino acid ionic liquids in improving spectral selectivity and sensitivity.1 1-octyl-3methylimidazolium ionic liquid[Csmin][Ala]was synthesised and as a fluorescence spectroscopy additive as an additive synchronous fluorescencespectrometry is proposed for simultaneous determination of magnolol(MN)and honokiol(HN)in traditional Chinese medicine Houpu.The overlapping fluorescence spectrum of MN and HN could be completely separated in the AAILs medium.Experiment parameters(the type and concentration of AAILs,pH values and temperature)were discussed.The detection limits of MN and HN reached 1.46 ?g/L,0.92 ?g/L and the recovery rates ranged from 98.6%-100.7%,99.7%-100.6%,respectively.Thismethods wassuccessfully employed for simultaneously determination of MN and HN in real samples.No significant differencescould befoundintheresults of this method and the pharmacopoeia of People's Republic of China 2015(Ch.P.2015).The experiment mechanisms were discussed by the Gaussian simulation and fluorescence quantum yield.2 1-hexyl-3-methylimidazolium tryptophan ionic liquid(TryIL)was synthesised and studied as a medium.It was showed that TryIL could self-aggregate into water/oil micellar in aqueous solution and N-GQD was assembled on hydrophilic part of TryIL micelle to construct a novel fluorescence "turn on-off' probe(N-GQD-TryIL).the fluorescence intensity was quenched through the formation of N-GQD-TryIL-Cu(II)complex due to the strong binding ability between Cu(II)and N-GQD-TryIL.In the following fluorescence "turn-on" step,the chiral ligand exchange between levodopa(LD)and Cu(II)-N-GQD-TryIL to partly recovery the fluorescence intensity.Corresponding influencing factors and mechanisms in fluorescence "turn-off" and"turn-on" process were discussed.Thus,a sensitive and selective fluorescence "turn off" and"turn on" platform for assay Cu(II)and LD was designed.Under the optimal conditions,Cu(II)and LD exhibited good linear relationship in the range of 0.051-16.00 ?g/mL and 0.55-5.00?g/mL.The LOD of them was 0.017 ?g/mL and 0.16 ?g/mL respectively.This method was successfully applied to the determination of Cu(II)and LD in real samples.Moreover,N-GQD-TryIL performed application prospects in bio-imaging due to protein affinity of the hydrophilic part.3 Poly amino acid ionic liquid:poly-1-vinyl-3-butylimidazolium glutamic acid(p-1-VbmGlu)was prepared for the first time and the synthesis conditions were optimized.It was founded up-conversion.fluorescence property from the three-dimensional fluorescence properties of p-1-VbmGlu.The fluorescence could be selectively quenched by Fe(III)but not responded to Fe(II).In H2O2 medium,Fe(II)and H2O2 have a strong quenching effect on the probe.Under the control of H2O2,p-1-VbmGlu was employed as a fluorescent probe for Fe(II)/Fe(III)speciation analysis.The detection limits were as low as 0.11 and 0.08 ?mol/L and the relative standard deviations was 1.1%and 2.0%.The method was successfully applied to the morphological analysis of Fe(?)/Fe(?)in serum and plant samples,with the satisfactory analytical results.4 A novel method based on amino acid ionic liquids aqueous bi-phase system([C6mim][Gly]-K3PO4)coupled with inductively coupled plasma-atom emission spectrometry(ICP-AES)to extract/analysis Co(II)-EDTA was developed.Conditions of phase formation were established by phase diagrams.Extraction conditions,including pH,EDTA volume and temperature,were optimized by response surface methodology(RSM).The results indicated that Co(II)-EDTA could be enriched in[C6mim][Gly]phase with a satisfying extraction rate 96.1%.Limits of detection(LOD)and limit of quantification(LOQ)were 0.64?g/L and 2.13?g/L respectively.This method emerged lots of advantages,such as more environmentally friendly,larger extraction capacity,shorter extraction time and higher sensitivity.It has been successfully applied to analysis trace cobalt in multiple real samples.