The analytical performance of sample preparation procedure (A) consisting of simple PP with TCA is considered to be superior to procedure (B) and similarly as good as performing a SPE cleanup, procedure (C) in quantifying L-arginine, ADMA, and SDMA in human plasma using HPLC-FLD
. The developed HPLC-FLD
method with sample preparation procedure (A) proved to be both accurate with recoveries ranging from 91.5 [+ or -] 3.03% to 113 [+ or -] 8.21% and precise with CVs of no more than 5%.
Para la determinacion del limite de deteccion de las aflatoxinas totales, se utilizo el metodo HPLC-FLD
, basado en que las aflatoxinas [B.sub.1], [B.sub.2], [G.sub.1] y [G.sub.2] muestran fluorescencia natural, aunque las de tipo B1 y G1 muestran fluorescencia escasa, por ello se utilizo una celda electroquimica post-columna (KOBRA[R] CELL R-BIOPHARM RHONE Ltd, EUA) acoplada al HPLC, donde la muestra se hizo reaccionar con KBr (agente derivatizante).
Supernatants were transferred into vials for analysis using HPLC-FLD.
A specific, sensitive, and reproducible HPLC-FLD method was newly developed for the simultaneous determination of bergapten, imperatorin, notopterol, and isoimperatorin and this was in turn applied to the pharmacokinetic and excretion study of bergapten, imperatorin, notopterol, and isoimperatorin in rats after oral administration of N.
Using the HPLC-FLD method, each type of GOS gave rise to a distinct GOS profile Figure 1) except those from the same supplier which had identical profiles (data not shown).
The GOS content of the GOS-1A and B products seems to be overestimated (117-120%) using the new HPLC-FLD method, and the GOS content of the GOS-5 product seems to be underestimated (84%) using the HPLC-FLD method.
Spiked formulae were also analysed using the HPLC-FLD method (Table 2); in this case, recoveries were in the range 92-102%.
The precision of the HPLC-FLD method applied to GOS ingredients was determined by analysing each ingredient in duplicate on six different days on the same instrument by the same operator.
The precision of the HPLC-FLD method applied to the analysis of GOS containing infant formulae was determined by analysing two commercially available formulae on eight different days in duplicate, on two different instruments using two different columns, and by two different operators (Table 5).
However, using the HPLC-FLD method described here, it is possible to differentiate the GOS fraction having a DP [greater than or equal to] 3 from the GOS disaccharides and thus the contribution of the GOS to TDF can be accurately assessed.
The HPLC-FLD method has the advantage that only a single run is required and the analysing laboratory does not need access to the GOS ingredient.
The performance of the HPLC-FLD method is quite good for most products (both formula and GOS ingredients) with a few exceptions.