On‐chip chiral separation based on bovine serum albumin‐conjugated carbon nanotubes as stationary phase in a microchannel

Abstract

A novel method of chiral separation based on protein-stationary phase immobilized in a poly(methyl methacrylate) microfluidic chip was developed. BSA conjugated with the shortened carboxylic single-walled carbon nanotubes (SWNTs) was employed as the chiral selector. Successful separation of tryptophan enantiomers was achieved in less than 70 s with a resolution factor of 1.35 utilizing a separation length of 32 mm. This is the first example of chiral separation based on SWNTs-BSA conjugates as stationary phase immobilized in microchip channel. The stability of the stationary phase in the channel was examined by microchip electrophoresis with laser-induced fluorescence detection. Factors that influenced the chiral separation resolution were examined. Under the optimized conditions, the proposed modified chip revealed adequate repeatability concerning run-to-run. These results show that the use of SWNTs-BSA conjugates within microfluidic channels hold great promise for a variety of analytical schemes.

Application of Carbon Nanotubes in Chiral and Achiral Separations of Pharmaceuticals, Biologics and Chemicals

“…The stability of this novel protein-SWCNTsstationary phase was confirmed using microchip electrophoresis MCE [60]. There was no separation of the racemic mixture of tryptophan in the absence of SWCNTs-BSA [60]. Upon adding 0.075-0.1 mg/ml of SWCNT-BSA conjugates, however, baseline separation was observed and then enhanced by increasing the concentration of SWCNT-BSA conjugates.…”

“…The schematic flow for the production of SWCNTs-BSA is shown in Figure 8. [60] SWCNTs conjugated BSA was immobilized in a PMMA microchannel for the separation of tryptophan using microchip electrophoresis (MCE) [60]. The stability of this novel protein-SWCNTsstationary phase was confirmed using microchip electrophoresis MCE [60].…”

“…[60] SWCNTs conjugated BSA was immobilized in a PMMA microchannel for the separation of tryptophan using microchip electrophoresis (MCE) [60]. The stability of this novel protein-SWCNTsstationary phase was confirmed using microchip electrophoresis MCE [60]. There was no separation of the racemic mixture of tryptophan in the absence of SWCNTs-BSA [60].…”

“…FT-IR spectroscopy was used for the identification of the carboxylic SWCNTs. Then, the short carboxylic SWCNTs were dispersed in water using ultrasonic agitation [60]. The carboxylic SWCNTs were then attached with BSA via a diimide-activated amidation reaction in the presence of EDAC under ultrasonication [119].…”

Chiral Carbon Nanotubes and Carbon Nanotube Chiral Composites: Preparation and Applications

“…A successful chiral separation was performed by using bovine serum albumin (BSA) functionalized shortened carboxylic SWNTs as stationary phase. 49 The SWNTs-BSA was immobilized in a poly(methyl methacrylate) micro°uidic chip as chiral selectors, and e±cient separation of tryptophan enantiomers was achieved in less than 70 s with a resolution factor of 1.35 by microchip electrophoresis, indicating the promising application of SWNTs in chiral separations. A mixture of SWNTs and cellulose trisphenylcarbamate or SWNTs inked to the 6-position of cellulose 2, 3-bisphenylcarbamate were found to possess high enantioseparation ability in high-performance liquid chromatography (HPLC).…”