... based on the forced transport of the polymer molecules through the porous
stationary-phase media under the conditions of suppressed interactions of the
263
HPLC for Pharmaceutical Scientists, ... in
reversed-phase chromatography applications for example, if the area% does
not agree with the assay% value for pharmaceutical analysis of a particular
active pharmaceutical ingredient...
... metabolites are
important biotransformation pathways for many drugs and xenobiotics [127,
132, 133]. For example, the formation of acyl glucuronide conjugate forced the
withdrawal of four marketed ... intermediates
for formation of the keto acid, were also observed in the radiochromatogram
of rat plasma (spectrum not shown) [131].
PRACTICAL APPLICATIONS 335
Scheme 11. Mechanism for th...
... addition, forced decomposition studies must also be performed for dif-
ferent dosage forms (capsule, tablet, suspension, injectable, etc.) of the same
drug substance.
688 ROLE OF HPLC DURING FORMULATION ... (capsule dosage form) of
the development compound A with aspirin was proposed. The preformulation
TEST METHODS FOR MOST COMMON DOSAGE FORMS 689
Figure 15-2. HPLC chromatogram obtai...
... (17+,18+,
19+,20+) for the reduced form, indicating a more open form of protein struc-
ture for protonations upon disulfide-bonds reduction. Furthermore, the mol-
ecular weight information obtained ... several
isoforms in addition to the target protein, as shown in its reversed-phase
APPLICATIONS FOR BIOTECHNOLOGY PRODUCTS AND DRUG TARGETS 851
HPLC chromatogram (Figure 19 -6). Two of t...
... by the pressure limitation
of the HPLC equipment. For more information on gradient separation and
developing fast HPLC methods, see Chapter 17 and Practical HPLC Method
Development from Synder ... 0.2- or 0.45-µm-pore-size
filter is generally recommend for removal of particulates [15]. Filtration as a
preventive maintenance tool for HPLC analyses is well-documented in the lit-
er...
... The experiments for
w
w
pH 2–4 were performed on day
1, and those for
w
w
pH 5–7 were performed on day 2 (≈36 hr after initial prepa-
ration).A further investigation was performed by preparing ... height) for peak B ≤ 1.5
•
Tailing factor (5% peak height) for peak A ≤ 1.5
•
Rt for peak A must be 12.0 ± 1.3 min
•
Rt for peak B must be 21 ± 1.0 min
•
The S/N of the LOQ solution (0...