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ANANBIOANAL - 2010
Pharmaceutical R & D Summit
doi:10.4172/2155-9872.1000070
ICP-MS Coupling to HPLC to Quantify Unknown Metabolite of
Drugs in Biological Fluids
Simona Rizea Savu1
, Martin Maurer1
, Luigi Silvestro1
Pharma Serv International SRL, Bucharest, Romania
, Ariana Tudoroniu2
13S-Pharmacological Consultation & Research GmbH, Harpstedt, Gernany
2
Introduction: The application of HPLC-MS/MS in pharmacokinetic studies has
been extremely helpful permitting to solve complex metabolism problems; it
remains however a main problem to quantify the newly identified metabolites until
a quantitative standard is available. Aiming to quantitate the concentrations of
unknown metabolites in absence of adequate quantitative standards, ICP-MS has
been combined to HPLC and, as an example, experimental results obtained on
clopidogrel, a potent antiaggregant and antithrombotic drug characterized by an
extensive metabolization, are here presented.
Materials and methods: This research was carried out using triple quadrupole
MS/MS systems (API-4000 and API 5000 Applied Biosystems) and a quadrupolar
ICP-MS (ELAN 6100 Perkin Elmer). HPLC separations were carried out (Agilent or
Perkin ELmer HPLC pumps) on reversed phase or ion exchange columns eluted
with different mobile phases in gradient or isocratic conditions. HPLC-MS and MS/
MS analyses were performed in positive or negative ions mode in order to get the
maximum of chemical structure information; in case of ICP-MS chromatographic
traces with masses characteristic of sulfur were acquired. Plasma samples collected
from subjects treated orally with clopidogrel as well samples obtained by “in vitro”
metabolization of clopidogrel were analyzed and compared with a few synthetic
clopidogrel metabolite standards.
Results and conclusions: Results obtained using different models of HPLC-
ICP interfaces and mobile phase composition will be presented. Under adequate
conditions of mobile phase composition and flow rate the application of ICP-MS to
HPLC proved to be an effective tool to quantify known and unknown clopidogrel
metabolites.
, Adriana Iordachescu2
, Constanta Dulea2
ANALBIOANAL-2010
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