| Autor: |
Shelor CP; Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, Texas 76019-0065, United States., Yoshikawa K; Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, Texas 76019-0065, United States., Dasgupta PK; Department of Chemistry and Biochemistry, University of Texas at Arlington, Arlington, Texas 76019-0065, United States. |
| Jazyk: |
angličtina |
| Zdroj: |
Analytical chemistry [Anal Chem] 2021 Apr 06; Vol. 93 (13), pp. 5442-5450. Date of Electronic Publication: 2021 Mar 24. |
| DOI: |
10.1021/acs.analchem.0c05089 |
| Abstrakt: |
Many of the universal detectors in liquid chromatography, including mass spectrometry, must completely volatilize the chromatographic eluent first before further processing and detection of the analytes. A basic requirement is that the eluent does not contain a nonvolatile dissolved component. However, separation of biomolecules must be conducted in mostly aqueous media of compatible pH and ionic strength if their biological activity must survive the separation process. Combinations of ammonia with acetic and formic acids are commonly used as eluent for this purpose but generally maximum concentrations that can be tolerated are relatively low. Further, buffering is good only over a limited pH range. We describe a system where the eluent is generated in an automated pressure-programmed manner from high-purity gaseous NH 3 and CO 2 through gas-permeable membrane devices. This can be aided by the prior presence of formic/acetic acids in the mobile phase to extend the attainable low pH limit. We outline the fundamental pH, ionic strength, and buffer intensity considerations and demonstrate the application of such eluents in the separation of amino acids, proteins, and monoclonal antibodies. We also demonstrate the use of dissolved CO 2 as an ion-pairing agent in the separation of chiral amines. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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