Continuous lipase B-catalyzed isoamyl acetate synthesis in a two-liquid phase system using corning® AFR™ module coupled with a membrane separator enabling biocatalyst recycle

In this article, a comprehensive review of applications of the hollow fibre-liquid phase microextraction (HF-LPME) for the isolation and pre-concentration of pharmaceuticals in water samples is presented. HF-LPME is simple, affordable, selective, and sensitive with high enrichment factors of up to 27,000-fold reported for pharmaceutical analysis. Both configurations (two- and three-phase extraction systems) of HF-LPME have been applied in the extraction of pharmaceuticals from water, with the three-phase system being more prominent. When compared to most common sample preparation techniques such as solid phase extraction, HF-LPME is a greener analytical chemistry process due to reduced solvent consumption, miniaturization, and the ability to automate. However, the automation comes at an added cost related to instrumental set-up, but a reduced cost is associated with lower reagent consumption as well as shortened overall workload and time. Currently, many researchers are investigating ionic liquids and deep eutectic solvents as environmentally friendly chemicals that could lead to full classification of HF-LPME as a green analytical procedure.

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Correlation of biocatalytic activity in an organic-aqueous two-liquid phase system with solvent concentration in the cell membrane

Enzyme and Microbial Technology ◽

10.1016/0141-0229(90)90100-5 ◽

1990 ◽

Vol 12 (4) ◽

pp. 281-291 ◽

Cited By ~ 104

Author(s):

S.J. Osborne ◽

J. Leaver ◽

M.K. Turner ◽

P. Dunnill

Keyword(s):

Liquid Phase ◽

Cell Membrane ◽

Phase System ◽

Solvent Concentration

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The two liquid phase system NaAl(ethyl)4 – benzene–HMPA

Canadian Journal of Chemistry ◽

10.1139/v85-482 ◽

1985 ◽

Vol 63 (11) ◽

pp. 2906-2914 ◽

Cited By ~ 4

Author(s):

James H. Medley ◽

Naseer Ahmad ◽

Marion C. Day

Keyword(s):

Liquid Phase ◽

Nmr Spectra ◽

Sodium Ion ◽

Phase System ◽

Quadrupole Relaxation ◽

Lower Phase ◽

Molar Ratios ◽

H Nmr ◽

Liquid Phases ◽

Solute Species

A detailed study of complexation of the sodium ion by HMPA2 has been made using the system[Formula: see text]where HMPA is observed to be a strong donor towards Na+ but does not complex AlEt4−. This system forms two liquid phases at low HMPA:Na+ molar ratios with the salt and the HMPA, up to a 4:1 HMPA:Na+ ratio, occurring only in the lower phase. Based on a variety of experimental techniques, reasonable proposals of the solute species in the lower phase as a function of HMPA:Na+ ratio are presented. A 2.5:1 ratio of HMPA:Na+ is observed to be particularly significant. This ratio is rationalized in terms of a bridging HMPA molecule resulting in a cationic species with the stoichiometry [2Na•5HMPA]2+. It is found that the 27Al and 1H nmr spectra are determined primarily by quadrupole relaxation of the 27Al nucleus rather than by exchange.

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