4th EucheMs chemistry congress

Poster Session 2
s1139
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - Analytical Chemistry
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deterMinAtion of BroMhexine on CArBon
PASte eLeCtrode uSinG differentiAL PuLSe
voLtAMMetry And fiA with AMPeroMetriC
deteCtion
J. MiKA 1 , A. neMeCKovA 1 , J. ziMA 1 , J. BAreK 1 ,
h. deJMKovA 1
1 Charles University in Prague Faculty of Science, Department
of Analytical Chemistry, Prague, Czech Republic
Bromhexine is frequentlyused mucolytic agent and
therefore, there is a demand for its fast and reliabledetermination.
Thanks to its chemical structure, bromhexine is a suitablecandidate
for electrochemical determination.
This fact was used for the development of new methods of
determinationbased on differential pulse voltammetry (DPV) and
flow injection analysis (FIA)with amperometric detection on
glassy carbon paste electrode (GCPE) in a wall-jetarrangement.
Optimum determination conditions of analysis were found.
Incase of DPV, the optimum supporting electrolyteconsists of
methanol and Britton-Robinson (B-R) buffer pH 9.0 (80:20, v/v).
Theoptimum conditions for the FIA determination are: carrier
solutionconsisting of methanol and ten times diluted B-R buffer
pH 9.0 (80:20, v/v),detection potential +1.1 V, flow rate
1.5 mL min –1 ,the injected volume 100 μL, The possibility to
increase sensitivity of DPV by preliminary adsorptionstep was
tested with 5 min accumulation time, but significant decrease of
detectionlimit was not obtained. The limit of detection for FIA
was 0.9×10 –8 mol L –1and for DPV 5.8×10 –7 mol L –1 . Applicability
of the methods was tested by determination of realsamples of
pharmaceutical preparations.
Acknowledgement: The researchwas supported by the Ministry
of Education, Youth and Sports of the Czech Republic (Project
MSM 0021620857), Charles University in Prague (Project SVV
2012-265201) and Grant Agencyof the Czech Republic(Project
P206/12/G151).
Keywords: Bromhexine; Glassy carbon paste electrode;
Differential pulse voltammetry; Flow injection analysis;
Amperometric detection;
4 th EucheMs chemistry congress
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hPLC/uv Method for deterMinAtion of
SeLeCted BenzodiAzePineS
M. MuChA 1 , J. KALinA 1 , P. KurKA 2
1 University of Ostrava Faculty of Science, Chemistry, Ostrava,
Czech Republic
2 University Hospital Ostrava, Department of Forensic
Medicine, Ostrava, Czech Republic
introduction: Benzodiazepines are the most popular
psychotropic drugs by doctors and drug addicts in the present. They
are used mainly as sedatives, anxiolytics or as premedication before
elective surgery due to its depressant effects on central nervous
system. The side effects are mainly fatigue and sleepiness [1, 2] . The
aim of this work was to developed HPLC/UV method for
determination of six benzodiazepines (Alprazolam, Bromazepam,
Clonazepam, Diazepam, Chlordiazepoxide and Oxazepam).
experimental part: It was used ammonium acetate and
formic acid for the preparation of mobile phase A. Acetonitrile
was used as mobile phase B. Six powder standards of
benzodiazepines, which were dissolved in methanol, was used
further. The method was developed on the instrument Agilent
1200, which was equipped with a column Gemini 5μ C18 110A.
The developed method was tested (its limits of detection (LOD)
and quantification (LOQ), linearity, reproducibility, repeatability,
precision and accuracy were determined).
results: The developed method had following parameters:
mobile phase A – 0.01M ammonium acetate + 0.1% (v/v)
formic acid, mobile phase B – acetonitrile, total flow of mobile
phase – 0,34 – 0,17 μl/min, mobile phase B gradient – 15 – 90%
(0 – 17 min), column temperature – 20°C and spray – 20 μl.
The parameters of method were following: LOD – 0,1 μl/min,
LOQ – 0,2 μl/min, correlation linearity coefficients higher than
0,985, deviation of reproducibility and repeatability better
than ±7% and deviation in precision and accuracy better
than ±7%.
Conclusion: The obtained HPLC/UV method for
determination of six benzodiazepines is suitable for introduction
into practical usage in hospital laboratories.
references:
1. Lüllmann, Heinz, Klaus Mohr a Martin Wehling.
Farmakologie a toxikologie. Praha: Grada Publishing, a.s.,
2004. ISBN 80-247-0836-1.
2. Rasková, Helena, Jirí Vanecek, Zdenek Votava a Max
Wenke. Farmakologie: učebnice pro lékařské fakulty.
2. edition. Praha: Avicenum, 1970.
Keywords: Liquid chromatography; Medicinal chemistry;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc