Histidine-tagged shiga toxin B subunit binding assay: simple and specific determination of gb3 content in mammalian cells

A two-step binding assay for globotriaosylceramide (Gb3) content was developed by histidine-tagging strategy, which is a well-established method for the purification of recombinant proteins. The complete binding of the recombinant His-tagged Shiga toxin 1B subunit (1B-His) (1 microg/ml) to the standard Gb3 adsorbed on a multi-well H type plate was observed within 30 min at 37 degrees C; and its binding could be visualized by the following applications of HisProbe-HRP (8 microg/ml) and tetramethylbenzidine (TMB) peroxidase substrate. The 1B-His binding assay was linear over the range of 1 to 100 ng of Gb3 per well. The binding of 1B-His was specific to Gb3 separated from HeLa cells, and no major cross-reactivity of other glycolipids in Folch's lower fractions extracted from HeLa cells was detected. The glycolipids in Folch's lower fractions from HeLa cells, human fibroblasts and mouse heart were suitable for this assay, but the further purification was needed for glycolipids from human plasma, thus sample preparation is critical factor for the reliable determination of Gb3 content. The 1B-His binding to Gb3 was inhibited by the addition of galactose, but not mannose. This 1B-His binding assay will be useful not only for the determination of Gb3 content, but also for screening for the compounds which inhibit the toxin-binding to Gb3. The strategy of our present method may be applicable for other binding assay, such as Cholera toxin B-subunit for ganglioside GM1.     

Synthesis, a case of isostructural packing, and antimicrobial activity of silver(I)quinoxaline nitrate, silver(I)(2,5-dimethylpyrazine) nitrate and two related silver aminopyridine compounds

The synthesis and low temperature crystal structures of [Ag(quinoxaline)]n(NO3)n, 1, [Ag(2,5-dimethylpyrazine)(NO3)]n, 2 and [Ag4(3-aminopyridine)4(NO3)4]n 3 are presented. The quinoxaline compound forms a 1D coordination polymer with the characteristic linear 2-coordination figure of silver(I), the N-Ag-N angle being 164.2(1) degrees, and only weak silver-nitrate interactions. In addition there is an interaction giving pairs of parallel chains as the main structural theme. The 2,5-dimethylpyrazine compound has approximately trigonal-planar coordination, also binding one nitrate at the relatively short Ag-O distances 2.444(3) angstroms and 2.484(3) angstroms, respectively, for the two crystallographically different silver atoms. This also results in a 1D coordination polymer that, despite the large differences in the Ag(I) coordination environment, is isostructural with 1. [Ag4(3-aminopyridine)4(NO3)4]n 3 forms a 2D coordination polymer by bridging nitrate ions. The antimicrobial activity of 1-3, and also of [Ag3(2-aminopyridine)4](NO3)3, 4 was screened for 13 different pathogens and substantial activity was shown for 1 against Escherichia coli and Pseudomonas aeruginosa (MIC 4 microg cm(-3)) and somewhat lower activity was registered against Sarcina lutea and Salmonella typhi for 1, Bordetella bronchiseptica for 2, Salmonella typhi and Pseudomonas aeruginosa for 3, and Escherichia coli and Shigella sonnie for 3 (MIC 8 microg cm(-3)). Only low activity was shown against the yeast Candida albicans for 1, 2 and 4 whereas no activity against this pathogen was registered for 3.     

钙钛矿型稀土复合氧化物催化剂上一氧化碳的选择氧化

考察了在钙钛矿型稀土复合氧化物催化剂上，氢气中一氧化碳选择氧化的催化性能，发现该催化剂具有优良的催化活性和选择性。LaMnO3中的锰被铜部分取代后可以提高其催化活性，当其中的镧再被锶或钡部分取代后所得的催化剂的催化活性进一步提高。其中以La0.8Sr0.2Mn0.5Cu0.5O3的催化活性为最佳，在该催化剂上，在40 000 mL·g－1·h－1下，155 ℃时CO可被完全转化为CO2，此时的选择性达54%，与铂催化剂的性能相近。反应气中加入CO2时，CO转化率下降，但选择性有所提高；加入水蒸气则使CO的转化率和反应选择性均下降。     

Affinity adsorption of recombinant human interferon-α on a porous dye-affinity adsorbent

Interferons are potent biologically active proteins synthesized and secreted by somatic cells of all mammalian species. Dye-affinity adsorption is increasingly used for protein separation. Hollow fibers have several advantages as adsorbents in comparison to conventional bead supports because they are not compressible and they eliminate internal diffusion limitations. The aim of this study was to explore in detail the performance of polyamide hollow fibers to which Cibacron Blue F3GA was attached for adsorption of recombinant interferon-α (rHuIFN-α). The hollow fiber was characterized by scanning electron microscopy. These dye-carrying hollow fibers (35.8 μmol/g) were used in the rHuIFN-α adsorption-elution studies. The effects of initial concentration of rHuIFN-α, medium pH, ionic strength and temperature on the adsorption efficiency of dye-attached hollow fibers were studied in a batch system. The non-specific adsorption of rHuIFN-α on the hollow fibers was 1.2 mg/g. Cibacron Blue F3GA attachment significantly increased the rHuIFN-α adsorption up to 99.8 mg/g. Significant amount of the adsorbed rHuIFN-α (up to 94.8%) was eluted in 1 h in the elution medium containing 1.0 M NaCl. In order to determine the effects of adsorption conditions on possible conformational changes of rHuIFN-α structure, fluorescence spectrophotometry was employed. We resulted that dye-affinity hollow fibers can be applied for rHuIFN-α adsorption without causing any significant conformational changes. Repeated adsorption/elution processes showed that these dye-attached hollow fibers are suitable for rHuIFN-α adsorption.     

Direct immersion solid‐phase microextraction with gas chromatography and mass spectrometry for the determination of specific biomarkers of human sweat in melted snow

To provide a reliable tool for investigating diffusion processes of the specific components of the human odor 3‐hydroxy‐3‐methylhexanoic acid and 3‐methyl‐3‐sulfanylhexan‐1‐ol through the snowpack, we developed and optimized an analytical method based on direct immersion solid‐phase microextraction followed by gas chromatography with mass spectrometry. Direct immersion solid‐phase microextraction was performed using polyacrylate fibers placed in aqueous solutions containing 3‐hydroxy‐3‐methylhexanoic acid and 3‐methyl‐3‐sulfanylhexan‐1‐ol. After optimization, absorption times of 120 min provided a good balance to shorten the analysis time and to obtain suitable amounts of extractable analytes. The extraction efficiency was improved by increasing the ionic strength of the solution. Although the absolute extraction efficiency ranged between 10 and 12% for 3‐hydroxy‐3‐methylhexanoic acid and 2–3% for 3‐methyl‐3‐sulfanylhexan‐1‐ol, this method was suitable for analyzing 3‐hydroxy‐3‐methylhexanoic acid and 3‐methyl‐3‐sulfanylhexan‐1‐ol concentrations of at least 0.04 and 0.20 ng/mL, respectively. The precision of the direct immersion solid‐phase microextraction method ranged between 8 and 16%. The variability within a batch of six fibers was 10–18%. The accuracy of the method provided values of 88–95 and 86–101% for 3‐hydroxy‐3‐methylhexanoic acid and 3‐methyl‐3‐sulfanylhexan‐1‐ol, respectively. The limit of detection (and quantification) was 0.01 ng/mL (0.04 ng/mL) for 3‐hydroxy‐3‐methylhexanoic acid and 0.06 ng/mL (0.20 ng/mL) for 3‐methyl‐3‐sulfanylhexan‐1‐ol. The signal versus concentration was linear for both compounds (r² = 0.973–0.979). The stability of these two compounds showed that 3‐hydroxy‐3‐methylhexanoic acid was more stable in water than 3‐methyl‐3‐sulfanylhexan‐1‐ol. We applied the method to environmental samples in correspondence with an olfactory target buried previously.     

Total synthesis and proof of relative stereochemistry of (-)-aureonitol

Two trisubstituted epimeric tetrahydrofurans, 1 and 2, have been synthesized in order to confirm the relative stereochemistry in the natural product aureonitol. The key step in the synthesis of 1 and 2 involved a stereoselective intramolecular allylation of an allylsilane with an aldehyde, which introduced the stereotriad in the five-membered ring. The major tetrahydrofuran diastereoisomer 18 from this cyclization reaction was subsequently elaborated to tetrahydrofuran 1. Its 3-epimer (2) was then prepared from 1 via an oxidation-reduction sequence. Compound 1 exhibits identical (1)H NMR data to those reported for aureonitol, which was isolated from Helichrysum aureonitons by Bohlmann in 1979, whereas the (1)H NMR data for 2 are markedly different. The (1)H NMR data (in CDCl3, CD3OD, and C6D6) and (13)C NMR data (in CDCl3) for 1 are also identical with those reported for a natural product isolated from various Chaetomium sp. by Abraham, Seto, and Teuscher. These findings support Abraham's conclusion that the structure of aureonitol should be revised from 2 to 1. The enantioselective synthesis of 1 has also confirmed that (-)-aureonitol isolated by Abraham contains the (2S,3R,4S) absolute configuration of stereocenters on the tetrahydrofuran ring.     

Kinetic study of the daytime atmospheric fate of (z)-3-hexenal

Rate coefficients for three daytime atmospheric reactions of (Z)-3-hexenal (3HA)-photolysis (J(1)), reaction with OH radicals (k(2)), and reaction with ozone (k(3))-were measured at 760 Torr and 298 K using a 6 m(3) photochemical reaction chamber. The UV absorption cross sections (σ(3HA)(λ)) were obtained in the wavelength range 240-350 nm. The photodissociation rate of 3HA relative to that of NO(2) was measured by a solar simulator at 760 Torr and was determined to be J(1)/J(NO2) = (4.7 ± 0.4) × 10(-3). Using the obtained σ(3HA)(λ) and J(1)/J(NO2), the effective photodissociation quantum yield was calculated to be Φ(3HA) = 0.25 ± 0.06. The rate coefficient for the reaction with OH radicals was measured by the relative rate method with three reference compounds and was determined to be k(2) = (6.9 ± 0.9) × 10(-11) cm(3) molecule(-1) s(-1). The rate coefficient for the reaction with ozone was measured by an absolute method and was determined to be k(3) = (3.5 ± 0.2) × 10(-17) cm(3) molecule(-1) s(-1). Using the obtained rate coefficients, the daytime atmospheric lifetime of 3HA was estimated.     

Evaluation of ammonia as diluent for serum sample preparation and determination of selenium by graphite furnace atomic absorption spectrometry

A method for the determination of total selenium in serum samples by graphite furnace atomic absorption spectrometry was evaluated. The method involved direct introduction of 1:5 diluted serum samples (1% v/v NH₄OH+0.05% w/v Triton X-100^®) into transversely heated graphite tubes, and the use of 10 μg Pd+3 μg Mg(NO₃)₂ as chemical modifier. Optimization of the modifier mass and the atomization temperature was conducted by simultaneously varying such parameters and evaluating both the integrated absorbance and the peak height/peak area ratio. The latter allowed the selection of compromise conditions rendering good sensitivity and adequate analyte peak profiles. A characteristic mass of 49 pg and a detection limit (3s) of 6 μg 1⁻¹ Se, corresponding to 30 μg l⁻¹ Se in the serum sample, were obtained. The analyte addition technique was used for calibration. The accuracy was assessed by the determination of total selenium in Seronorm™ Trace Elements Serum Batch 116 (Nycomed Pharma AS). The method was applied for the determination of total selenium in ten serum samples taken from individuals with no known physical affection. The selenium concentration ranged between 79 and 147 μg l⁻¹, with a mean value of 114±22 μg l⁻¹.     

Gas chromatographic determination of some alkoxysilanes for use in occupational exposure assessment

The manufacture and application of organosilicon compounds, especially silanes, have increased dramatically during recent decades. This has led to an increase in the number of exposed workers in different areas of industry. Therefore, there is an urgent need for an analytical method which can assess exposure to these compounds. A capillary column gas chromatographic (GC) method was developed for detecting 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane and 3-aminopropyltriethoxysilane. The silanes diluted in heptane were analysed by GC using flame ionisation detection. Gas chromatography-mass spectrometry was used to confirm the identity of the GC peaks. The analytical range of the method varied from 1 or 5 micrograms ml-1 to 500 micrograms ml-1 depending on the silane being studied. The detection limits were 1 microgram ml-1 for 3-methacryloxypropyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane and 5 micrograms ml-1 for 3-aminopropyltriethoxysilane. The mean recovery of silanes tested with patch samples was > 95% for all of the silanes. The repeatability of the patch sample method for silanes varied from 6.5 to 10.1%. This new GC method allows the simultaneous determination of three organosilicon compounds for occupational exposure assessment.     

Determination of vitamins D2, D3, K1 and K3 and some hydroxy metabolites of vitamin D3 in plasma using a continuous clean-up-preconcentration procedure coupled on-line with liquid chromatography-UV detection

A semi-automatic procedure for the continuous clean-up and concentration of several fat-soluble vitamins prior to their separation by HPLC and UV detection is reported. The procedure is based on the use of a minicolumn packed with aminopropylsilica as sorbent located prior to the chromatographic detection system. The overall process was developed and applied to the main liposoluble vitamins (A, D2, D3, E, K1, K3) and several hydroxy metabolites of vitamin D3 [25-(OH)-D3,24,25-(OH)2-D3 and 1,25-(OH)2-D3]. All the analytes were monitored at a compromise wavelength of 270 nm. Calibration graphs were constructed between 0.01 and 100 ng ml-1 for vitamin D2 and D3 and their hydroxy metabolites, between 0.1 and 100 ng ml-1 for vitamin A, K1 and K3 and between 1 and 100 ng ml-1 for vitamin E, with excellent regression coefficients (> or = 0.9901) in all cases. The precision was established at two concentration levels with acceptable RSDs in all instances (between 3.6 and 8.7%). The method was appropriate for the determination of vitamin D2, D3, K1 and K3 and the 24,25-dihydroxy and 25-hydroxy metabolites of vitamin D3 in human plasma. The method was applied to plasma samples spiked with the target analytes and the recoveries ranged between 78 and 109%.     

可见光下改性的纳米孔二氧化硅(LUS-1)光催化苯直接羟基化合成苯酚(英文)

Fe-g-C3N4-LUS-1 was prepared by the thermal decomposition of dicyandiamide inside the pores of LUS-1 under an inert atmosphere.It was used as a photocatalyst for the hydroxylation of benzene to phenol in sunlight.The catalysts were characterized by Fourier transform infrared spectroscopy,N2 adsorption-desorption,X-ray diffraction,and scanning electron microscopy.In Fe-g-C3N4-LUS-1,a single layer of graphitic carbon nitride(g-C3N4) was formed on the surface of LUS-1.The photocatalytic activity of the iron containing g-C3N4 based catalysts was investigated,and the catalytic activity was remarkably enhanced when the reaction condition was changed from dark to sunlight.The best result was obtained with 20%Fe-g-C3N4-LUS-1 in sunlight.     

Synthesis and evaluation of new potential HIV-1 non-nucleoside reverse transcriptase inhibitors. New analogues of MKC-442 containing Michael acceptors in the C-6 position

Analogues of MKC-442 capable of undergoing Michael addition reactions were synthesised in order to investigate the activity against the HIV-1 mutant (Y181C). An improved activity was postulated on the basis of a possible covalent binding to the mercapto group of Cys181. Lithiation of the C-6 position of 1-ethoxymethyl-5-ethyl-1H-pyrimidine-2,4-dione (5) was followed by reaction with alpha,beta-unsaturated aldehydes and oxidation of the alcohols formed to give the alkenoyl analogues 1a-3a. Analogues 1b-3b containing an allyloxymethyl group in the N-1 position instead of the ethoxymethyl group could not be synthesised due to isomerisation of the allylic group during the metallation reaction. The NMR data for compounds 1a-3a showed a hindered rotation, which was more pronounced for the 6-cyclohexenylcarbonyl derivative 3a than for the propenyl derivatives 1a and 2a. Moderate activity against wild type HIV-1 was observed for the alcohol 8 and the ketones 2a-3a. However, no activity was observed against the Y181C mutant.     

O(1D)+Si(CH3)3Cl反应生成振动激发的OH(ν≤3)

The vibrationally excited OH(v) from the reaction of O(~1D)+Si(CH_3)_3Cl was observed by UV laser photolysis/FTIR emission spectroscopy. The vibrational number was only up to 3 with a ratio of 1:0.8:0.1 for v=1:2:3. Comparing this result with the similar reaction of O(~1D)+Si(CH_3)_4 which OH(v) vibrational number was high up to 4 with a ratio of 1:1:1:0.3 for v=1:2:3:4 under the same experimental conditions, it was found that the substitution of Cl for CH_3 affected the extent of heavy Si atom blocking the energy migration in a molecule. This results identifies the prediction that the characteristic of electrons in central atom plays an important role in intramolecular energy transfer.     

Ce3+对大白鼠和豚鼠心肌的影响

研究了Ｃｅ＾３＋对离体豚鼠心房收缩,离体豚鼠乳头肌及在体大白鼠心肌动作电位的影响。浓度为０．０５ｍｍｏｌ．Ｌ＾－１的Ｃｅ＾３＋溶液可抑制豚鼠右心房的自律性和左心房的收缩。０．１和０．２ｍｍｏｌ．Ｌ＾－１Ｃｅ＾３＋溶液对豚鼠乳头肌动作电位时程影响不显著。     

Determination of atmospheric nitrobenzanthrones by high-performance liquid chromatography with chemiluminescence detection.

A method using high-performance liquid chromatography with chemiluminescence detection was developed for analyzing mutagenic nitrobenzanthrone (NBA) isomers in airborne particulates. The method was a modification of our previously described method for analyzing nitropolycyclic aromatic hydrocarbons (NPAHs). The pretreatment and reducing conditions for 1-, 2-, 3- and 10-NBAs were the same as those for NPAHs. In order to separate these NBA isomers, we used a polymeric-type ODS column (Cosmosil 5C-18MS); a mixture of 40% acetonitrile and 60% 10 mM imidazole-HClO4 buffer was employed as the mobile phase at a flow rate of 1 mL/min. The isomers of 1-, 2-, 3- and 10-NBA were determined in chemiluminescence with linear calibration graphs from 0.1 to 4 pmol, from 200 to 4000 pmol, from 1 to 50 pmol and from 10 to 400 pmol, respectively. The detection limits (S/N = 3) of 1-, 2-, 3- and 10-NBA isomers were 0.02 pmol, 35 pmol, 0.3 pmol and 3 pmol, respectively. The method was used to analyze airborne particulates at a heavy traffic site in Kanazawa. 2- and 3-NBAs were detected in the extracts of the particulates, while 1-NBA and 10-NBA were not detected. The atmospheric concentrations of 2- and 3-NBAs were 1.83 pmol/m3 and 24.7 fmol/m3, respectively.     

水合偏硼酸钾的热化学研究

Hydrated potassium monoborate(KBO₂·4/3H₂O) was obtained from an aqueous solution in a mole ratio of K₂O∶B₂O₃=2∶1 and characterized by powder X-ray diffraction(XRD)， infrared spectroscopy(FT-IR) and Raman spectroscopy. The enthalpy of solution of hydrated potassium monoborate， KBO₂·4/3H₂O， in approximately 1mol·dm^-3 aqueous hydrochloric acid was determined. Together with the previously determined enthalpies of so-lution of H₃BO₃ in approximately 1mol·dm^-3 HCl(aq) ，and of KCl in aqueous(hydrochloric acid+boric acid)， the standard molar enthalpy of formation of -(1411.11±0.84)kJ·mol^-1 for KBO₂·4/3H₂O was obtained from the standard molar enthalpies of formation of KCl(s)， H₃BO₃(s)， and H₂O(l). The standard molar entropy of formation of -422.94J·K^-1·mol^-1 and standard molar entropy of 163.47J·K^-1·mol^-1 for KBO₂·4/3H₂O were calculated from the thermodynamic relations. A group contribution method is applicable to KBO₂·4/3H₂O.     

Mapping the triplet potential energy surface of 1-methyl-8-nitronaphthalene

Spin-unrestricted calculations and time-dependent DFT were used to characterize structure and reactivity of 1-methyl-8-nitronaphthalene (1) in the triplet state. Four hybrid models (B3LYP, PBE0, MPW1K, BHLYP) with significantly different amount of the exact exchange were employed. The triplet potential energy surface of 1 was mapped by using the UB3LYP and UMPW1K techniques. Both hybrid models provided qualitatively consistent pictures for the potential energy landscape. Thirty-one stationary points, of which 15 were minima, were found at the UB3LYP level of theory. Three minima corresponding to the nitro form of 1 were located on the triplet surface; just one was found for the singlet ground state. Two reaction paths leading from 1 either to a nitrite-type intermediate (2) or to the aci-form (3) were characterized. For both paths, reaction products were of diradical nature. The lower activation energy was obtained for the triplet-state tautomerization affording 3. The ground state of triplet multiplicity was predicted for two isomers of the aci-form. The triplet diradical 3 is expected to react through the thermal population of a close-lying singlet excited state. The results are discussed in relation to mechanisms of photoinduced rearrangements of peri-substituted nitronaphthalenes that can be used to develop novel photolabile protecting groups.     

Mechanised flow system for on-line microwave digestion of food samples with off-line catalytic spectrophotometric determination of cobalt at ng l-1 levels

A mechanised system for on-line slurry food sample digestion was developed and an off-line cobalt determination was performed. The stabilised slurry sample was introduced into an air carrier stream until reaching the digestion coils located inside a household microwave oven. Software written in Visual Basic 3.0 was developed to permit the transport of the slurry samples and the programming of the microwave oven and also the control of the mineralization valve. The proposed system was optimized for determination of cobalt in certified samples such as mussels, bovine liver and fish and also uncertified fish samples. The digestion parameters were established as 3 mol l-1 HNO3 for mussels, 3 mol l-1 HNO3 plus 0.16% v/v H2O2 for bovine liver and 12 mol l-1 HNO3 for fish employing maximum power for 5 min of microwave actuation. In the subsequent spectrophotometric method for the catalytic determination of cobalt, the Tiron and hydrogen peroxide concentrations were 1.8 x 10(-3) and 3.0 x 10(-4) mol l-1, respectively, and the sample residence time was 300 s as determined by an optimisation process. The proposed method features a linear range from 10 to 200 ng l-1 Co (r > 0.996) with detection and quantification limits of 1.7 and 5.5 ng l-1 Co, respectively. The precision, expressed as RSD, was 2.4% (n = 12) for repeatability and 5.2% (n = 10) for reproducibility and the accuracy of the proposed method was assessed by using certified samples and an alternative technique (ETAAS).     

Specific binding of GM1-binding peptides to high-density GM1 in lipid membranes

The ganglioside Galbeta1-3GalNAcbeta1-4(Neu5Acalpha2-3)Galbeta1-4Glcbeta1-1'Cer (GM1) is an important receptor. We have previously identified GM1-binding peptides based on affinity selection from a random peptide library. In the present study, we determined the amino acids essential for binding GM1 and investigated the specific interaction with GM1 in the lipid membrane. Arginines and aromatic amino acids in the consensus sequence (W/F)RxL(xP/Px)xFxx(Rx/xR)xP contributed to the ability of the peptides to bind GM1. The peptide p3, VWRLLAPPFSNRLLP, having the consensus sequence, showed high affinity for GM1 with a dissociation constant of 1.2 microM. Furthermore, the density-dependent binding of p3 was investigated using mixed monolayers of GM1 and Glcbeta1-1'Cer (GlcCer). p3 binds preferentially to high-density GM1, and its interaction with GM1 was found to be cooperative based on a Hill plot. These results indicated that a lateral assembly of GM1 molecules was required for the recognition of carbohydrates by p3. The GM1-binding peptide played a role as a unique anti-GM1 probe differing from the cholera toxin B subunit or antibodies.     

Property of ionic liquid in electrophoresis and its application in chiral separation on microchips

The aqueous solution of a kind of room-temperature ionic liquids (RTILs), 1-ethyl-3-methylimidazolium-tetrafluoroborate (1E-3MI-TFB), demonstrated its exclusive electroosmotic property in microchip electrophoresis. It was applied as the working electrolyte for chiral separation in glass microchip electrophoresis. Compared with boric acid buffer, 1E-3MI-TFB aqueous solution exhibited a broader separation window for enantiomers of dipeptides. Then the influences of chiral selector, pH and concentration on efficiency of chiral separation were discussed in detail. The unique mechanism of the generation of EOF was explored in a glass microchannel using 1E-3MI-TFB aqueous solution as working electrolyte. A possible status of 1E-3MI cation in water was suggested at the first time, which facilitated the explanation of EOF and its characteristics in glass microchannel. Additionally, microchip electrophoresis using 1E-3MI-TFB aqueous solution was successfully applied to the chiral separation of complex enantiomers of dipeptides. RTILs aqueous solution, as the electrolyte for the separation of complicated optical isomers, could lead to a revolution in the analytical methods of chiral or conformational analysis for biomolecules.