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Current Pharmaceutical
Analysis
ISSN: 1573-4129
Current Pharmaceutical
Analysis
Volume 2, Number 1, February 2006
Contents
Applications of Stripping Voltammetry at Carbon Paste
and Chemically Modified Carbon Paste Electrodes to Pharmaceutical
Analysis Pp. 1-8
Abd-Elgawad Radi
[Abstract]
Review: Sample Concentration Based on Inclusion of Organic
Solvents in Capillary Zone Electrophoresis Pp. 9-15
Zak Shihabi
[Abstract]
Method Development and Validation for the Direct Determination
of Cefepime in Human Serum by Micellar Electrokinetic Capillary
Chromatography Pp. 17-21
Toshihiro Kitahashi and Itaru Furuta
[Abstract]
Alkyl Chloroformates in Sample Derivatization Strategies for
GC Analysis Review on a Decade Use of the Reagents as Esterifying
Agents Pp. 23-43
Petr Hušek
and Petr Šimek
[Abstract]
Biochemical Micro-Techniques in the Diagnosis and
Classification of Amyloidosis Pp. 45-52
Batia Kaplan, Brian M. Martin, Avi Livneh, Mordechai PRAS
and Gloria Gallo
[Abstract]
Analytical Methodologies for Chloramphenicol Residues Determination
in Food Matrixes: A Brief Review Pp. 53-57
Lúcia Santos and Fernando Ramos
[Abstract]
Main Active Components of St. John’s Wort (Hypericum
Perforatum) Extracts: Current Analytical Procedures for
Pharmacokinetics and Concentration-Response Studies Pp.
59-68
Silvio Caccia
[Abstract]
F2-Isoprostanes: Review of Analytical Methods
Pp. 69-78
Olivier Berdeaux, Olivier Scruel, Jean Luc Cracowski
and Thierry Durand
[Abstract]
The impact of Self-Assembly in Medicine and Pharmacology
Pp. 79-83
Mahnaz Derakhshan, Hamid Reza Ansarian, Makoto Takafuji,Toshihiko
Sakurai and Hirotaka Ihara
[Abstract]
Establishment of Conditionally Immortalized Cell Lines
with Specific Functions and its Application to Differential
Gene Expression Analysis by DNA Microarray Technology
Pp. 85-93
Yoshiaki Tabuchi, Takashi Kondo and Masuo Obinata
[Abstract]
Abstracts
[Back to top]
Applications of Stripping Voltammetry at Carbon Paste
and Chemically Modified Carbon Paste Electrodes to Pharmaceutical
Analysis
Abd-Elgawad Radi
In this review, the analytical applications of carbon paste
electrodes for pharmaceutical analysis are summarized, and
future prospects examined, especially in connection with chemically
and biologically modified carbon paste electrodes.
[Back to top]
Review: Sample Concentration Based on Inclusion of Organic
Solvents in Capillary Zone Electrophoresis
Zak Shihabi
Capillary electrophoresis, as an analytical tool for drugs,
offers several advantages for pharmaceuticals and clinical
applications; however, it suffers from poor detection limits.
Concentration on the capillary (stacking) improves greatly
this problem and is very easy to perform. One of the simple
and practical methods to perform stacking is dissolving the
sample in organic solvents and injecting a large volume of
sample on the capillary. This leads to concentration of the
sample 10-30 folds directly on the capillary, removes the
excess of proteins found in biological fluids and overcomes
the deleterious effects of salts. The stacking can be performed
in both the hydrodynamic and electroinjection. This stacking
brings the detection limits of the CE closer to that of the
HPLC. The mechanism, practical applications, different factors,
and optimum conditions for this type of stacking are reviewed
and discussed.
[Back to top]
Method Development and Validation for the Direct Determination
of Cefepime in Human Serum by Micellar Electrokinetic Capillary
Chromatography
Toshihiro Kitahashi and Itaru Furuta
A method for determining the concentration of cefepime,
a cephem anti-microbial agent, by direct serum injection using
micellar electrokinetic capillary chromatography is developed
and its validation of the assay is studied. A borate buffer
(100 mM; pH 8.0) containing sodium dodecyl sulfate (80 mM)
is used as a run buffer. Ultraviolet detection is carried
out at 260 nm. The migration time of cefepime is about 5.2
min. The limit of detection is 0.5 mg/l (S/N=3). The RSD’s
of intra-day and inter-day precisions are 1.57-4.08 % (6.8-94.2
mg/l) and 1.47-2.75 % (10.2-81.5 mg/l), respectively, and
the recovery rate is 94-108%. 13 other cephem anti-microbial
agents are measured under the analytical conditions of this
method and the results show that cefatrizine, whose migration
time coincides with that of cefepime, interferes with the
determination of cefepime. This method is characterized by
the ability of allowing analysis by the direct injection of
serum samples of micro-quantities into the capillary.
[Back to top]
Alkyl Chloroformates in Sample Derivatization Strategies
for GC Analysis Review on a Decade Use of the Reagents as
Esterifying Agents
Petr Hušek
and Petr Šimek
The neccessity to derivatize polar analytes prior to separation
often disqualifies gas chromatography (GC) as a method of
choice in the field of biomedical/pharmaceutical analysis.
Laborious and lengthy protocols for treating compounds prior
to the analysis were discouraging. Only few derivatization
approaches were well-established over decades, primarily silylations.
To its assets belongs universality and efficacy, to shortcomings
necessity for dry residue and prolonged reaction time, often
under heating. Similarly, the next field-proven esterification-acylation
two-step procedures suffered from the same pre-requisites.
Current investigations in the field of derivatization turned
attention to chemical reactions proceeding in aqueous environment
and obviating multiple reaction steps and heating. Application
of alkyl chloroformates (RCF), under conditions discovered
more than a decade ago, met such criteria. Instantaneous conversion
of hydrophilic compounds to organophilic ones became often
an integral part of sample preparation procedures with neg-ligible
time and costs required. This review attempts to bring forward
some of the most important studies on RCF-mediated derivatizations
in the last decade and to figure out general utility of the
approach in analyzing polar organic compounds by GC, with
particular attention to polyfunctional organic acids, especially
amino acids (AAs).
[Back to top]
Biochemical Micro-Techniques in the Diagnosis and
Classification of Amyloidosis
Batia Kaplan, Brian M. Martin, Avi Livneh, Mordechai PRAS
and Gloria Gallo
Amyloidosis refers to a heterogeneous group of disorders
characterized by the extracellular deposition of amyloid proteins
in various tissues of the body. About 25 different amyloid
proteins originating from presumably normal precursor proteins
have been described so far. Identification of the chemical
nature of amyloid is necessary in clinical practice, since
both prognosis and treatment regimens are different in the
various amyloidoses. This review is aimed at summarizing the
new biochemical micro-techniques for precise typing of amyloid
proteins in diagnostic biopsy specimens. The reported micro-techniques
vary with respect to the state of the amyloid-bearing tissue,
i.e., unfixed-frozen or formalin-fixed, the purification strategy
(chromatographic or electrophoretic) and the analytical method
used (ELISA, Western blotting, amino acid sequencing, mass
spectroscopy). The utility and advantages of the described
protocols are discussed with regard to tissue state, sample
size, amyloid content, simplicity of procedures and possible
applicability in diagnostic laboratories.
[Back to top]
Analytical Methodologies for Chloramphenicol Residues Determination
in Food Matrixes: A Brief Review
Lúcia Santos and Fernando Ramos
Chloramphenicol (CAP) is a broad-spectrum antibiotic, effective
against a wide range of microorganisms, and has widely been
used since the 1950’s to treat food-producing animals.
However, CAP has been rapidly associated to serious toxic
effects, especially bone marrow depression, particularly severe
when it assumes the form of the dose-independent and fatal
aplastic anaemia.
The well-known risk of irreversible bone marrow disorders
and the absence of safe residue levels has determined European
Union (EU) prohibition for veterinary use, in 1994, and no
maximum residue limit (MRL) has been established for this
antibiotic. Despite this legal ban, CAP has recently been
found in several animal-derived foods, mainly aquaculture
products.
In order to prevent illegal use, it is important to develop
analytical methodologies that provide performance limits capable
of detecting and quantifying residual levels of this antibiotic.
In this paper, the authors present a review of the most relevant
procedures for sampling, pre-treatment, extraction/purification
and determination of CAP residues in different food matrixes,
published in the literature for the past decade. A special
focus will be given to gas chromatography – mass spectrometry
(GC-MS) and liquid chromatography – tandem mass spectrometry
(LC-MS/MS), as they represent the most modern and reliable
analytical methodologies for determination of CAP residues.
[Back to top]
Main Active Components of St. John’s Wort (Hypericum
Perforatum) Extracts: Current Analytical Procedures for
Pharmacokinetics and Concentration-Response Studies
Silvio Caccia
The complete spectrum of active compounds of Hypericum
perforatum (St. John’s wort) has not yet been fully
elucidated, but some naphthodianthrones (hypericin and pseudohypericin),
phloroglucinols (hyperforin) and flavonoids (primarily quercetin
glycosides) are thought to be essential for the antidepressant
activity of its extracts. Some of these compounds modulate
the expression of the P-glycoprotein transporter or of cytochrome
P450 enzymes or both although, again, their real role in clinically
relevant interactions involving the extracts and conventional
drugs is still not clear. Analysis of main components in body
fluids and tissues has thus become of interest in studies
to identify and characterize those accounting for the primary
and secondary pharmacological effects, which can help in providing
safe and effective dosing regimens with the appropriate extracts.
Selective procedures such as high-performance liquid chromatography
with fluorimetric, electrochemical, ultraviolet or photodiode
detection or coupled with mass spectrometry, depending on
the constituent, have been frequently used. This review provides
an overview of these methods, and the related sample pre-treatment
procedures. The focus is also on their sensitivity and precision
and consequently their reliability for pharmacokinetic studies
in relation to the blood and, when animal data are available,
brain concentrations of the main active components of Hypericum
perforatum extracts.
[Back to top]
F2-Isoprostanes: Review of Analytical Methods
Olivier Berdeaux, Olivier Scruel, Jean Luc Cracowski
and Thierry Durand
F2-isoprostanes (F2-isoPs) represent
a new family of biomarkers for oxidative stress generated
by free radical attack of membrane-bounded arachidonic acid.
Esterified F2-isoPs can be found in tissue or plasma
lipids whereas the free form F2-isoPs, hydrolyzed
by phospholipase, is mainly present in body fluids. The extent
of systematic damage due to oxidative stress within the body
can be assessed by the determination of plasma or urine F2-isoPs.
The determination of F2-isoPs in clinical practice
is not often used due to the complexity to extract the compounds
from their biologic matrixes before the analysis step. In
most of published protocols, extraction procedure is critical
and time-consuming, requiring successive chromatographic steps.
Moreover, some of these procedures lead to a substantial loss
of target compounds. In order to improve sample preparation
steps and final recovery, others methods have been developed
and optimized. For detection of F2-isoPs, two main
analytical approaches have been adopted. The first one involves
immunological methods and the second approach is based on
chromatographic separation and detection by mass spectrometry.
A large amount of works has been done in the field of isoprostane
analysis, but until now, no standardized method seems to emerge.
Indeed, described methodologies differ either in the sample
preparation steps or in the detection techniques or both.
In the present review, the most commonly used methods are
presented and compared in terms of extraction, purification,
and analysis of F2-isoPs, taking into account the
various origins of biological samples.
[Back to top]
The impact of Self-Assembly in Medicine and Pharmacology
Mahnaz Derakhshan, Hamid Reza Ansarian, Makoto Takafuji,Toshihiko
Sakurai and Hirotaka Ihara
The concept, molecular self-assembly, especially considering
molecule-molecule interaction as an information-processing
phenomenon, have a profoundly novel effect on thoughts and
efforts related to Medicine and Pharmacology. This new style
of thinking is still too novice to be used solely and independently
for explanation of disease mechanisms and appropriate treatment
strategies. However it calls for a range of new researches
based on new predictions about disease mechanisms (especially
Autoimmune diseases, Endocrinopathies, and Neoplasms) and
relevant treatment strategies (superstructural drugs).
[Back to top]
Establishment of Conditionally Immortalized Cell Lines
with Specific Functions and its Application to Differential
Gene Expression Analysis by DNA Microarray Technology
Yoshiaki Tabuchi, Takashi Kondo and Masuo Obinata
Immortalized cell lines that retain differentiated functions
are required to study tissue functions at cellular and molecular
levels. Transgenic animals, mice and rats, harboring temperature-sensitive
simian virus 40 large T-antigen have been found to be very
useful for establishing conditionally immortalized cell lines
from tissues that have proved difficult to culture in
vitro. Thus far we have succeeded in establishing many
kinds of conditionally immortalized cell lines with differentiated
functions from the transgenic animals. Novel DNA microarray
technologies allow the simultaneous measurement of changes
in expression of many hundreds or many thousands of genes.
Using established cell lines and DNA microarrays, we have
identified many genes that are differentially expressed in
the process of cell differentiation and cell death. In this
review, we would like to introduce the characteristics of
established gastrointestinal and testicular cell lines and
discuss possible applications of these cell lines to differential
gene expression analysis by DNA microarray technology.
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