The Use of Poly(Sodium N-Undecanoyl-l-Leucylvalinate), Poly(Sodium N-Undecanoyl-l-Leucinate) and Poly(Sodium N-Undecanoyl-l-Valinate) Surfactants as Chiral Selectors for Determination of Enantiomeric Composition of Samples by Multivariate Regression Modeling of Fluorescence Spectral Data

Abstract

Steady-state fluorescence spectroscopy was employed to investigate the use of chiral polymeric surfactants as chiral selectors in chiral analysis by multivariate regression modeling of spectral data. Partial-least-squares regression modeling (PLS-1) was used to correlate changes in the fluorescence spectral data of 1,1'-bi-2-naphthol (BOH), 1,1'-binaphthyl-2,2'-diamine (BNA), or 2,2,2-trifluoroanthrylethanol (TFA) in the presence of poly(sodium N-undecanoyl-L-leucylvalinate), poly(sodium N-undecanoyl-L-leucinate) or poly(sodium N-undecanoyl-L-valinate) as the enantiomeric composition of the chiral analytes was varied. The regression models produced from the spectral data were validated by determining the enantiomeric composition of independently prepared test solutions. The ability of the model to correctly predict the enantiomeric composition of future samples was evaluated using the root-mean-square percent-relative error (RMS%RE) of prediction. In terms of RMS%RE, the ability of the model to accurately predict the enantiomeric composition of future samples was dependent on the chiral analyte, the polymeric surfactant used, and the surfactant medium, and ranged between 1.57 and 6.10%. Chiral analyte concentrations as low as 5 x 10(-6) M were found to give regression models with good predictability.

Determination of Enantiomeric Compositions of Analytes Using Novel Fluorescent Chiral Molecular Micelles and Steady State Fluorescence Measurements

“…A recent study in our laboratory has demonstrated the utility of molecular micelles as chiral selectors for determining the enantiomeric composition of three highly hydrophobic fluorescent chiral molecules using steady-state fluorescence spectroscopy and multivariate regression analysis of spectral changes in chiral guest-host complexes [26]. In this study, differences in analyte fluorescence emission were observed due to the formation of diastereomeric complexes between the chiral molecular micelle and chiral analyte.…”

“…We have previously reported that the extent of spectral variation will determine the prediction accuracy for enantiomeric composition [26]. Serine had the highest RMS%RE value and the lowest degree of spectral variation.…”

“…As a result, this FCMM was chosen for enantiomeric composition studies with these three analytes. Several studies have shown enantiomeric purity can be determined by partial-least-square-regression modeling of steadystate fluorescence spectral data of fluorescent chiral analytes [26,34,35]. Multivariate regression modeling for enantiomeric composition prediction is a two-phase process.…”

A versatile chiral selector for determination of enantiomeric composition of fluorescent and nonfluorescent chiral molecules using steady‐state fluorescence spectroscopy

“…Previous studies in our laboratory with nonfluorescent molecular micelles confirmed that the ability of the calibration model to accurately predict the enantiomeric composition of future samples depends on the extent of the spectral variation. 11 All analytes have the same total concentration (1.0 3 10 25 M), but different emission spectra with varying enantiomeric compositions in the presence of poly-L-SUF. Table 1 shows the compositions of 12 solutions prepared for the calibration of all eight analytes.…”

Synthesis and characterization of novel chiral ionic liquids and investigation of their enantiomeric recognition properties

“…Various chiral selectors, such as cyclodextrins, molecular micelles, antibody, and crown ethers have been widely used because of their chiral recognition abilities. [21][22][23][24] However, the use of many current chiral selectors is often limited because of low solubility, difficult organic syntheses, instability at high temperature, as well as high cost. In addition, many currently available chiral selectors require the use of another solvent and sometimes more than one solvent system if the analyte and the chiral selector are not soluble in the same solvent.…”