scholarly journals The identification of a lipid-mobilizing factor from sheep midbrain

1972 ◽  
Vol 130 (2) ◽  
pp. 467-473
Author(s):  
P. P. Shah ◽  
A. R. Tee ◽  
P. D. English ◽  
B. T. Redman ◽  
J. Bunyan

The mass spectrum of a lipolytic substance from purified sheep midbrain extract indicated that it was isoprenaline, not N-n-propylnoradrenaline, noradrenaline or adrenaline. The identification of the lipid-mobilizing factor as isoprenaline was confirmed qualitatively by t.l.c. and g.l.c. and quantitatively by determination of its lipolytic activity and u.v. absorption and by fluorimetric determination of its catecholamine content.

1989 ◽  
Vol 54 (3) ◽  
pp. 616-621 ◽  
Author(s):  
Záviš Holzbecher

It has been found that phosphoric acid decreases the first excitation maximum of Ce(III) at 256 nm, increases the second excitation maximum at 297 nm and shifts the fluorescence maximum from 350 to 346 nm. Under optimum conditions, with λexc = 297 nm and λem = 346 nm, Ce(III) can be determined fluorimetrically with a detection limit of 1.2 ng ml-1 in 12M-H3PO4 medium. No interference was observed from a 20-200 fold excess of HCl, H2SO4, Na, K, NH4+, Al and the rare earth elements. HNO3 interferes and Ce(IV) and Fe(III) interfere strongly. It follows from the stereofluorograms of Ce and Tb that the spectra of the two elements are practically independent. The detection limit for Tb(III) in 0.02-2.5M-H2SO4 medium for λexc = 222 nm and λem = 494 nm is 33 ng ml-1. No interference was observed from a 5-20 fold excess of Al3+ and the other rare earth elements. The determination is slightly less sensitive in H3PO4 or HCl medium. The relative standard deviation of the measurement for 10 ng ml-1 Ce(III) or 50 ng ml-1 Tb(III) is about 3%.


1994 ◽  
Vol 27 (5) ◽  
pp. 867-878 ◽  
Author(s):  
D. W. Bryce ◽  
J. M. Fernández-Romero ◽  
M. D. Luque de Castro

The Analyst ◽  
1985 ◽  
Vol 110 (1) ◽  
pp. 43-45 ◽  
Author(s):  
Soledad Rubio ◽  
Agustina Gómez-Hens ◽  
Miguel Valcárcel

2011 ◽  
Vol 54 (1) ◽  
pp. 57-65 ◽  
Author(s):  
N. V. Maksimenko ◽  
S. M. Kuchin
Keyword(s):  

Talanta ◽  
1999 ◽  
Vol 50 (1) ◽  
pp. 49-56 ◽  
Author(s):  
Tomás Pérez-Ruiz ◽  
Carmen Martı́nez-Lozano ◽  
Virginia Tomás ◽  
Jesús Martı́n

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