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Current Analytical Chemistry
ISSN: 1573-4110
Current Analytical Chemistry
Volume 2, Number 4, October 2006
Contents
Determination of Disulfide Functionality in Underivatised
Peptides Using Negative Ion Mass Spectrometry: An Aid to Structure
Determination Pp. 341-352
Daniel Bilusich and John H. Bowie
[Abstract]
Speciation Analysis of Non-Metallic Elements Using
Plasma Based Atomic Spectrometry for Detection Pp.
353-377
Rodolfo G. Wuilloud and Jorgelina C. Altamirano
[Abstract]
Analytical Procedures for the Preparation, Isolation,
Analysis and Preservation of Reduced Nicotinamides Pp.
379-388
Kelli A. Markham and Amnon Kohen
[Abstract]
Separation of Inorganic Anions and Cations by
High-Speed Ion Chromatography Pp. 389-396
Shiyun Ai and Qun Xu
[Abstract]
Design of Lanthanide Complex Probes for Highly
Sensitive Time Resolved Fluorometric Detection Methods and
Its Application to Biochemical, Environmental and Clinical
Analyses Pp. 397-410
Takeshi Matsuya, Nobuhiro Hoshino and Tsuneo Okuyama
[Abstract]
The Capillary Electrophoresis Based on Ionic Liquids
Pp. 411-419
Xingguo Chen and Shengda Qi
[Abstract]
Analysis of Phosphorus and Phosphorylated Compounds
in the Context of Plant Physiology and Global Phosphorus Management:
A Review Pp. 421-430
Henrik Brinch-Pedersen and Frank Hatzack
[Abstract]
Abstracts
[Back to top]
Determination of Disulfide Functionality in Underivatised
Peptides Using Negative Ion Mass Spectrometry: An Aid to Structure
Determination
Daniel Bilusich and John H. Bowie
This review outlines the mass spectrometric methods used
to identify disulfide functionality in peptides, particularly
cleavages from peptide (M-H)- parent anions. A
brief introduction to characteristic negative ion fragmentations
of peptides is given, including (i) the α
and β
cleavages which provide data analogous to that provided by
Y+2 and B cleavages of MH+
ions, (ii) characteristic side chain cleavages, and (iii)
γ backbone
cleavages initiated from anion sites on the side chains of
certain residues (e.g. Ser, Thr, Cys, Asp, Asn, Glu and Gln).
The cystine disulfide functionality is difficult to identify
from positive ion fragmentations of an MH+ parent
cation of an underivatised peptide. However, the –S-S-
group is readily identified by the diagnostic loss of the
elements of H2S2 from the (M-H)-
anion of the peptide. This process is anion directed (from
that cystine backbone enolate anion closest to the N-terminal
end of the peptide). The stepwise process is exothermic (by
4.6 kcal mol-1; calculations at the HF/6-31G(d)//AM1
level of theory) with a barrier of 9.1 kcal mol-1
to the highest energy transition state. If one of the cystine
residues is C-terminal with a terminal CO2H moiety,
the presence of a pronounced peak corresponding to the fragmentation
sequence [(M-H)- - (H2S2
+ CO2)]- identifies this functionality.
The studied fragmentation processes are charge initiated;
there is no evidence for the operation of any charge-remote
processes.
[Back to top]
Speciation Analysis of Non-Metallic Elements
Using Plasma Based Atomic Spectrometry for Detection
Rodolfo G. Wuilloud and Jorgelina C. Altamirano
In this review, a full discussion and update of the state-of-the-art
of separation techniques interfaced to plasma spectrometers
for speciation analysis of non-metallic elements, such as
iodine, chlorine, bromine and fluorine as well as phosphorus
and sulfur is presented. The plasma-based techniques covered
include inductively coupled plasma mass spectrometry (ICP-MS)
microwave-induced plasma optical emission spectrometry (MIP-OES),
and inductively coupled plasma optical emission spectrometry
(ICP-OES). Also, different variants of plasma sources, such
as low power plasmas and glow discharge (GD) sources are described
and compared with respect to their capabilities in elemental
speciation. Recent advances and alternative mass analyzers
(collision/reaction cell; time-of-flight; double-focusing
sector field) are also included. The discussion is centralized
on the application of the hyphenated methodologies involving
several types of separations such as liquid chromatography,
gas chromatography and electrophoresis coupled to plasma-based
detectors for speciation analysis of non-metals. This is presented
in different sections considering the analysis of several
matrices including environmental, biological and food samples,
as well as a last section related to the use of halogenated
compounds for plasma studies.
[Back to top]
Analytical Procedures for the Preparation, Isolation,
Analysis and Preservation of Reduced Nicotinamides
Kelli A. Markham and Amnon Kohen
Nicotinamide containing cofactors are ubiquitous in biological
systems. As a result, when studying nicotinamide dependent
systems in vitro or in vivo, isotopically
labeled nicotinamide cofactors are often used to reveal the
mechanism of the biological system of interest. The reduced
form of these cofactors is labile and is sensitive to light,
oxygen, pH, temperature and other factors. Consequently, their
synthesis, purification, analysis, and preservation have been
an on-going challenge. Due to these stability issues, studies
using nicotinamide cofactors, especially those utilizing the
reduced forms, have been relegated to repetitive cycles of
synthesizing the needed material just prior to experimental
use. Such practice is not practical in studies utilizing complex
isotopic labeling patterns. Many of the efforts that have
been reported for synthesis, separation and long-term preservation
of the various nicotinamide cofactors, led to procedures that
are no longer practical or cost effective while others present
the best solutions available today. Some of these efforts
are presented and compared in this mini-review. Herein we
describe our analytical and synthetic methodologies for the
synthesis, separation, purification, analysis and long term
preservation of labile nicotinamide cofactors, which achieve
excellent versatility, yields, purity, HPLC resolution, and
long term stability.
[Back to top]
Separation of Inorganic Anions and Cations by
High-Speed Ion Chromatography
Shiyun Ai and Qun Xu
Compare with normal liquid chromatography (LC), high-speed
ion chromatography (IC) has the benefits of fast analysis,
fast method development, and increased mass sensitivity. These
benefits start to attract more and more researchers’
attention. This review covers recent developments in high-speed
IC field, mainly focus on application of the inorganic anions
and cations determination; the review show that high-speed
IC mostly use monolithic stationary phases at high eluent
flow-rates.
[Back to top]
Design of Lanthanide Complex Probes for Highly
Sensitive Time Resolved Fluorometric Detection Methods and
Its Application to Biochemical, Environmental and Clinical
Analyses
Takeshi Matsuya, Nobuhiro Hoshino and Tsuneo Okuyama
Lanthanide complexes have been used for fluorescent labels
to the wide variety of analytical methods including high performance
liquid chromatography, immunoassay, and fluorescent imaging
with time-resolved fluorometric meas-urements. Introduction
of a time-resolved fluorometric measurement has been permitted
the easy distinction of a specific long-lived fluorescence
signal from short-lived natural background fluorescence present
in most biological samples, reaction wells and optical components.
Recently, new fluorescent labels and new instruments have
been reported for time-resolved fluorescence including high
performance liquid chromatography as in environmental analysis
as river water, clinical chemistry as allergen assay, and
a biochemical analysis as in staining method of proteins on
polyacrylamide gel. The time-resolved fluorometric detection
methods using new fluorescent labels improved the detection
sensitivity compared to those of previously-described methods.
This paper reviews those developments of applications of lanthanide
fluorescent labels for various purposes: time-resolved fluorometric
high performance liquid chromatography, time-resolved fluorescent
immunoassay, and protein staining in recent years.
[Back to top]
The Capillary Electrophoresis Based on Ionic
Liquids
Xingguo Chen and Shengda Qi
In this paper, the desirable physical-chemical properties
of ionic liquids, the method of ionic liquids used as running
electrolytes or modifier in aqueous and non-aqueous capillary
electrophoresis were introduced. The potential of capillary
electrophoresis based on ionic liquids was discussed throughout
the paper. The application status of capillary electrophoresis
based on ionic liquids in the analysis of the bioactive components
in traditional Chinese herbs, polyphenols, basic proteins,
metal ions, and so on were reviewed and summarized with the
illustrative use of recent literatures. In addition, the foreground
of capillary electrophoresis based on ionic liquids, as well
as its difficulties was also discussed.
[Back to top]
Analysis of Phosphorus and Phosphorylated Compounds
in the Context of Plant Physiology and Global Phosphorus Management:
A Review
Henrik Brinch-Pedersen and Frank Hatzack
The management of phosphorus (P) as a non-renewable resource
is receiving increasing attention at the dawn of the new millennium.
The importance of phosphate as a nutrient, the environment
phosphate load in areas with intens livestock production and
the depletion of the high quality phosphate resources are
accentuating the need of a holistic and global phosphorus-resource
management and understanding of the physiological roles, the
biosynthesis and the breakdown of phosphorylated compounds
in plants. Two important routes towards improved P-resource
management are genetic engineering of plants towards improved
P bioavailability and the application of microbial phytases
to increase the bioavailability of phytate-P in monogastric
animals. The present review gives an overview on these P-management
approaches and discusses the arsenal of analytical techniques
that can be used to analyze P and P-compounds. This analytical
capability is an important determinant in the development
of more advanced and more effective approaches towards P-resource
management.
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