1) Electrophoresis is a technique that separates ionized or dissolved analytes under the influence of an electric field due to their differing electrophoretic mobilities.
2) There are two main types of electrophoresis: free solution electrophoresis and gel electrophoresis. Capillary electrophoresis uses thin capillaries and has high separation efficiency for small molecules and biomolecules.
3) Key factors that affect electrophoretic mobility include the nature of the analyte, electrolyte properties, applied voltage, and capillary dimensions. Electroosmotic flow also influences analyte migration.
This document discusses capillary electrophoresis, a technique for separating charged molecules. It can separate proteins, peptides, amino acids, nucleic acids, and other molecules. Capillary electrophoresis works by applying an electric field across a thin capillary tube, which causes different molecules to migrate through the buffer at different rates based on their charge and size. It provides high separation efficiency using only small sample volumes. The document outlines the basic components and process of capillary electrophoresis.
This document describes research on the electrodeposition of titanium and titanium dioxide from ilmenite ore. Key findings include:
- Titanium and titanium dioxide can be extracted via electrolysis of leach solutions produced from ilmenite ore using acids or alkaline digestion.
- Suitable electrolyte bath compositions and electrodeposition conditions like current density and temperature were identified to produce titanium and titanium dioxide.
- The presence of positively and negatively charged titanium complex species in the electrolyte solutions was confirmed, and their roles in the electrodeposition processes were discussed.
- Current efficiencies as high as 99% were achieved using ammonia and urea baths for titanium deposition.
This document discusses capillary electrophoresis, a technique for separating charged molecules. It can separate proteins, peptides, amino acids, nucleic acids, and other molecules. Capillary electrophoresis works by applying an electric field across a thin capillary tube, which causes different molecules to migrate through the buffer at different rates based on their charge and size. It provides high separation efficiency using only small sample volumes. The document outlines the basic components and process of capillary electrophoresis.
This document describes research on the electrodeposition of titanium and titanium dioxide from ilmenite ore. Key findings include:
- Titanium and titanium dioxide can be extracted via electrolysis of leach solutions produced from ilmenite ore using acids or alkaline digestion.
- Suitable electrolyte bath compositions and electrodeposition conditions like current density and temperature were identified to produce titanium and titanium dioxide.
- The presence of positively and negatively charged titanium complex species in the electrolyte solutions was confirmed, and their roles in the electrodeposition processes were discussed.
- Current efficiencies as high as 99% were achieved using ammonia and urea baths for titanium deposition.
ELECTRODEPOSITION OF TITANIUM AND ITS DIOXIDE FROM ILMENITE Al Baha University
The aim of the present work was to develop a simple and rapid electrolytic extraction process of titanium [l-3] and its dioxide from the ilmenite ore of the Eastern Desert. The ore mother liquor used for the electrolysis process is either produced by direct leaching with 98% H,SO, (S/L = 1 : 15), 35% HCl (S/L = 1: 20) and alkaline digestion with caustic soda in a ball-mill autoclave at 175°C under a pressure of 9.5 kg cmP2, or it is prepared through the fusion method using NaOH or Na,S,O, separately as fluxes at 600-700°C.
This document provides information about electrophoresis. It discusses different types of electrophoretic techniques including slab electrophoresis, capillary electrophoresis, capillary zone electrophoresis, capillary gel electrophoresis, capillary isotachophoresis, and micellar electrokinetic chromatography. It also covers principles, instrumentation, applications in areas like DNA analysis and vaccine analysis.
Examination of methods to determine free-ion diffusivity and number density f...Weston Bell
This document summarizes a study that critically examines methods for determining free ion diffusivity and number density from analysis of electrode polarization. It shows that the commonly used Macdonald-Trukhan model of electrode polarization analysis fails to provide reasonable values at high salt concentrations. An empirical correction is proposed but caution is warranted as there is no solid theoretical justification. A variety of electrolyte materials, including polymer electrolytes, aqueous and nonaqueous solutions, and ionic liquids, were examined using dielectric spectroscopy and the results were compared to pulsed-field gradient NMR measurements.
This document provides supporting information for a research article on silicon nanowire solar cells. It describes the materials and methods used, including:
1) The synthesis of silicon nanowire cores and shells of different doping types using a home-built reactor.
2) Fabrication of nanowire devices, including contact deposition and measurements of current-voltage characteristics and quantum efficiency.
3) Finite-difference time-domain simulations of light absorption in nanowires compared to bulk silicon.
Los días 22 y 23 de junio de 2016 organizamos en la Fundación Ramón Areces un simposio internacional sobre 'Materiales bidimensionales: explorando los límites de la física y la ingeniería'. En colaboración con el Massachusetts Institute of Technology (MIT), científicos de este prestigioso centro de investigación mostraron las propiedades únicas de materiales como el grafeno, de solo un átomo de espesor, y al mismo tiempo más resistente que el acero y mucho más ligero.
Effect of inorganic fillers on Poly(ethylene oxide) crystallization and dynamicsEleni 'Hellen' Papananou
It is well known that the behaviour of polymers when they are restricted in space or when they are close to surfaces can be very different from that in the bulk. In this work, we investigate the morphology, crystallization and dynamics of a hydrophilic, semi-crystalline polymer, poly(ethylene oxide), PEO, when mixed with silica, SiO2, nanoparticles in a broad range of compositions. The good dispersion of the nanoparticles was verified by Transmission Electron Microscopy (TEM), whereas the morphology and crystallization behaviour of the hybrids were investigated with, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC). All techniques show a gradual decrease of polymer crystallinity with increasing the amount of nanoparticles; nevertheless, polymer crystallization is observed for all silica loadings. Moreover, DSC measurements showed the existence of two melting and crystallization transitions in hybrids with polymer content lower than 50wt%, indicating that the polymer crystallizes differently than the bulk near the silica surface
1. The document summarizes research using NMR techniques to investigate the presence of solid state water at room temperature in various hydrated materials, including zeolites, silicates, cement, and cellulose.
2. Deuterium NMR relaxation experiments on samples hydrated with D2O provide evidence for room temperature solid state water undergoing localized tetrahedral jumps or C2 rotations.
3. The results suggest a model where the solid state water is in fast exchange between tetrahedral and C2 motion configurations at room temperature.
The document describes research on photoelectrocatalytic degradation of salicylic acid using sprayed gold doped iron oxide thin films. Gold doped iron oxide films were deposited via spray pyrolysis and characterized. XRD showed the films were polycrystalline hematite. SEM showed needle-shaped grains of 100-150nm. Electrical resistivity decreased with gold doping up to 2%. The 2% gold doped film had the highest photocurrent and degraded 75% of salicylic acid in 320 minutes under visible light irradiation, making it the best photoelectrode developed in the study.
This document discusses different types of capillary electrokinetic separations including capillary zone electrophoresis, capillary gel electrophoresis, capillary electrochromatography, capillary isoelectric focusing, capillary isotachophoresis, and micellar electrokinetic capillary chromatography. It provides an overview of the basic components and design of capillary electrophoresis instrumentation. It also describes the types of molecules that can be separated including proteins, peptides, amino acids, nucleic acids, inorganic ions, organic bases, organic acids, and whole cells.
Kinetic modelling of nitrate removal from aqueous solution during electrocoag...Alexander Decker
This document discusses a study that aimed to model nitrate removal from aqueous solutions using electrocoagulation. Experiments were conducted to treat a synthetic solution containing 150 mg/L of nitrate using iron electrodes under various conditions. Kinetic and adsorption models were tested to determine which best fit the nitrate removal data. The results showed pseudo-second order kinetics and the Freundlich isotherm provided the best fits. Nitrate removal efficiency increased with reaction time and current density.
XPS is a surface-sensitive technique that uses X-rays to eject electrons from a material's surface and measure their kinetic energy. This provides information about the material's elemental composition, chemical state, and electronic structure within the top 10-100 angstroms. XPS works based on the photoelectric effect - X-rays eject core level electrons, and the electron binding energy is determined from the kinetic energy measurement and known X-ray energy. Each element produces characteristic peaks allowing identification. Chemical shifts provide information about chemical environment. XPS is widely used for materials characterization and analysis of thin films, corrosion, polymers, and more.
The principle and performance of capillary electrophoresisimprovemed
Capillary electrophoresis is a separation technique performed in narrow capillaries using high voltages and electric fields. It has high efficiency, requires small sample volumes, and operates quickly. Components migrate based on their electrophoretic mobility and electroosmotic flow. There are various modes that provide different selectivity, including capillary zone electrophoresis, capillary gel electrophoresis, micellar electrokinetic chromatography, and capillary electrochromatography. Capillary electrophoresis has numerous applications in biochemistry, pharmacology, toxicology, clinical chemistry, and forensics.
Los días 22 y 23 de junio de 2016 organizamos en la Fundación Ramón Areces un simposio internacional sobre 'Materiales bidimensionales: explorando los límites de la física y la ingeniería'. En colaboración con el Massachusetts Institute of Technology (MIT), científicos de este prestigioso centro de investigación mostraron las propiedades únicas de materiales como el grafeno, de solo un átomo de espesor, y al mismo tiempo más resistente que el acero y mucho más ligero.
XPS is a surface-sensitive technique that uses X-rays to eject electrons from the surface of a sample. It can be used to determine the elemental composition, empirical formula, chemical or electronic state of elements present in the surface. The principle is based on the photoelectric effect where X-rays eject core shell electrons of an atom. The kinetic energy of these photoelectrons is measured to determine the elemental identity and chemical state. XPS provides information down to 10-100 Angstroms from the surface and is useful for applications like failure analysis, corrosion studies, and analyzing thin film coatings and polymers.
This document describes a new method called polymer-aided stereodivergent synthesis (PASS) that allows the simultaneous preparation of both enantiomers of a chiral compound in discrete form. The key steps are: (1) A cyclization reaction on a polymer-supported quasi-meso substrate leads to the formation of quasi-enantiomers, with one immobilized on the polymer and the other free in solution. (2) Treatment with nucleophiles converts the quasi-enantiomers into the desired enantiomers. This new method was demonstrated through the synthesis of optically pure oxazolidinone enantiomers.
A two-part reaction was tested to investigate the regioselectivity and stereoselectivity of adding water to the sterically hindered bicyclic alkene nopol. Mercury(II) acetate was used to form an organomercuric intermediate, followed by sodium borohydride to reduce the mercuric group and add a hydrogen. While TLC and IR spectroscopy suggested the reaction occurred, limited product recovery prevented full NMR characterization to verify the desired alcohol product. Purification by column chromatography separated unreacted nopol but not individual products. Further work is needed to substantiate steric effects on stereochemical product formation.
ChemFET fabrication, device physics and sensing mechanismRichard Yang
1. Organic thin-film field-effect transistors (OTFTs) were fabricated and tested for chemical sensing applications. Pulsed gate operation was found to significantly reduce device baseline drift compared to static operation.
2. Charge transport in the organic semiconductor films occurs via multiple trapping and release of charge carriers. Variable temperature measurements showed thermally activated transport, with the activation energy dependent on gate voltage.
3. Exposure to chemical vapors causes a change in device characteristics due to the interaction of adsorbed analyte molecules with the doped organic semiconductor surface layer. This modifies both the surface doping level and trap energies.
Magnetic chitosan nanoparticles for removal of cr(vi) from aqueous solutionhbrothers
This document describes research on using magnetic chitosan nanoparticles for removing Cr(VI) from aqueous solutions. The researchers introduced a simple method to prepare magnetic chitosan nanoparticles via co-precipitation and epichlorohydrin cross-linking. Characterization showed the nanoparticles were spherical and around 30 nm in size. Adsorption experiments found Cr(VI) removal was highly dependent on pH, with maximum adsorption of 55.80 mg/g occurring at pH 3. Kinetic data fit a pseudo-second order model and isotherm data fit the Langmuir model well. The magnetic chitosan nanoparticles showed potential for use in wastewater treatment applications to remove Cr(VI).
Similar to Phuong phap dien di electrophoresis (20)
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
RHEOLOGY Physical pharmaceutics-II notes for B.pharm 4th sem students
Phuong phap dien di electrophoresis
1. Phöông Phaùp Ñieän Di
(Electrophoresis)
PGS.TS. Nguyeãn Ñöùc Tuaán
Boä moân Phaân Tích – Kieåm Nghieäm
Khoa Döôïc – Ñaïi hoïc Y Döôïc TPHCM
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
2. Phöông Phaùp Ñieän Di
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
Muïc tieâu
- Hieåu ñöôïc nguyeân taéc hoaït ñoäng cuûa ñieän di mao quaûn
Daøn baøi
- Lòch söû
- Ñònh nghóa
- Phaân loaïi
- Ñieän di mao quaûn
3. Lòch söû
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
1791 Faraday Laws of Electrolysis
1877 Helmholtz Charged Solvent Layer Closed to Surface of a Wall
1897 Nernst Properties of Small Ions
1897 Kohlrausch Kohlrausch Function describing the Order of Migration of Ions and their Concentration
1923 Kendall, Crittenden Rare Earth Metal Separation by "Ion Migraion Method"
1930 Tiselius Thesis: Moving Boundary Method for Electrophoresis of Proteins (Nobel Price 1948)
1939 Svenson Development of Zone and Displacement Electrophoresis
1950 Haglund, Tiselius Electrophoresis Tube filled with Glass Beads and Glass Powder
1955 Smithies Gel Electrophoresis
1958 Hjertén Electrophoresis in Free Solution
1967 Martin, Everaerts Displacement Electrophoresis in Glass Tube with Hydroxyethylcellulose
1967 Hjertén Elimination of Electroosmosis by Coating of Glass Tubes
1969 Giddings Non-Diffusional Model of Concentration Distribution in Free Zone Electrophoresis
1969 Virtanen Glass Capillaries 0.2 - 0.5 mm I.D.
1970 Everaerts, Capillary Isotachophoresis
1970 Arlinger, Routs UV-Detection
1972 Verheggen Conductivity Detection
1979 Mikkers Use of High Voltage and TEFLON Capillaries
1981 Jorgenson Use of 75 µm I.D. Open Tubular Glass Capillaries:
"High Performance Capillary Electrophoresis – HPCE"
1984 Terabe Combination of electrophoretic and chromatographic Separation:
"Micellar Electrokinetic Capillary Chromatography – MECC"
1991 Jandik, Jones Use of Surface Active Electrolyte Additives for Reversal of Electroosmotic Flow
1991 Knox "Capillary Electrochromatography – CEC"
8. Phaân loaïi
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
Ñieän di veät (ñieän di vuøng:
Zone Electrophoresis)
Söû duïng chaát mang:
giaáy, cellulose acetat, gel
agar, gel polyacrylamid
EP phuï thuoäc vaøo E, baûn
chaát tieåu phaân, doøng bay
hôi (nhieät Joule), dung
dòch ñieän giaûi
Taùch caùc chaát coù PTL
nhoû vaø kích thöôùc nhoû,
löôïng maãu ít
Điện di trên gel
9. Ñieän di mao quaûn (Capillary Electrophoresis)
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
High Voltage Power Supply
0-±30 kV
5-150 A
Injection
hydrostatic,
vacuum,
electromigrative
Data Processing
Separation Electrolyte
Salt solution (borate,
phosphate); pH 1-12
organic solvent
(0-100%)
Pt Electrodes
Capillary
o.d. 200-400µm
i.d. 5-100µm (2µm)
Fused Silica, Teflon
coated (RP, Ion exchange)
or filled (RP, ...)
Detector
UV, Fluorescence (direct,
indirect); electrochemical
conductometric
MS
10. Ñieän di mao quaûn
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
50µm12µm
363µm
Fused Silica Capillary
Hydrodynamic flow profile and
chromatographic peak form
a) pressure driven
b) electroosmosis
a)
b)
Ohm's Law: U=R.I
U [kV]
I [µA]
0 10 20
50
100
150
0
30
200
250
300
Liquid cooling
10m/s air cooling
w/o cooling
11. Doøng ñieän thaåm (Electroosmotic Flow)
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
Origin of Electroosmotic Flow:
a) Formation of negatively charged silica-surface
b)Hydrated cations at surface
c) Bulk flow of whole capillary contents towards cathode
after application of electric field
i
iiA czeN
Tk
....1000
..
22
= Thickness of Layer
= dielectricity constant
k = Boltzmann-constant
T = temperature
NA = Avogadro-constant
e = charge per unit surface area
z = charge of ion
c = molar concentration
-
+
+
+
+
+
oriented and non-
oriented water molecules
outer Helmholtz-Layer (diffuse)
inner Helmholtz-Layer (adsorbed, rigid)
r
Y1
Y2
Capillary
Electrolyte
Solvated Cations
Solvated Anions
(van der Waals)
+
+
e4
21 YY
Silanol groups in fused silica capillaries
SiO O Si
O
O
O O O
H H H
O Si
O Si
O
O
H H
O Si
O
H
O
O
H H
O
primary
sekundary tertiary
Hydrolysis:
Si-O-
Thickness of
Layer
eof
= Zeta-Potential [V]
Y1 = Stern-Potential [V]
Y2 = Potential of bulk solution [V]
µeof = Mobility of EOF [cm2V-1sec-1]
= Dielectricity constant of electrolyte
= Viscosity of electrolyte
Electroosmotic
mobility
12. Linh ñoä ñieän di (Electrophoretic Mobility)
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
F qEE
)(
)(
F
E
ep
FForcefrictional
FForceelectric
F rF ep
6
eprqE 6
ep
qE
r
6
ep
ep
E
q
r
6
Mobility in Infinitely Diluted Solutions
C+
N A-
0 1 2 3 4 5
C+: Cations
Trimethylphenylammonium bromide
Histamine
4-Aminopyridine
N: Neutral Molecules
Benzylalcohol
Phenol
A-: Anions
Syringaldehyde
2-(p-Hydroxyphenyl)acetic acid
Benzoic acid
Vanillic acid
4-Hydroxybenzoic acid
Overlay of Migration of Charged Ions and Molecules
with EOF
a) Cations to Cathode (Detection before EOF).
b) Neutral Moleculese (Detection together EOF).
c) Anions to Anode (Detection for |µAnion| < |µeof| after EOF;
no Detection for |µAnion| > |µeof |)
13. Linh ñoä ñieän di (Electrophoretic Mobility)
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
Dissociation of Weak Electrolytes
%ionhóa
14. Nguyên tắc của điện di mao quản vùng
(Capillary Zone Electrophoresis, CZE)
obs(A
+
) = EOF + EP(A
+
)
obs(C
-
) = EOF - EP(C
-
)
obs(N) = EOF
0 1 2 3 4 5 6(t)
A+ B+ C- D-
EOF
N-
+
-
µ-
ep
+
µ+
ep
electrophoretic
mobility
cations from the
electrolyte
µeof
very important
parameter!
electroosmotic
flow
15. Separation principle of MEKC
capillary wall
µEOF
µep+eof (A+)
= µep+eof (B-)
µep (A
+
)
µep (B-)
µmicelle
SDS
A+
C
µep(A+solub) µobs (A
+
)
µobs (B-)
µobs (C)
µobs (M)
0 1 2 3 4
C A+
EOF
B- M
5 6(t)
B-
16. Thoâng soá thöïc nghieäm trong CE
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
Analyte geometry
molecular weight,
structure
pKA
ionic strength
effective
charge
capillary wall
capillary length
high voltage V
field strength
E=V/L
wall
eof
r
q
ep
6
tot = eof + ep
ep = µep.E
eof = µeof.E
viscosity
permittivity
adsorption pH
solvation
Electrolyte
Instrument
22. Caùc thuoác khaùng HIV
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
Capillary, L=48.5 cm, leff=40 cm, 50
µm; electrolyte, 16 mM phosphate,
0.001% HDB, pH 2.5
Injection, 20 sec @ 10 mbar; standard
concentration, 5 ppm;
Separation, -30 kV
Detection, UV @ 195 ± 5 nm (bubble
cell 200 µm).
AMP...amprenavir; RTV...ritonavir;
SQV...saquinavir; NFV...nelfinavir;
IDV...indinavir
0
1
2
3
4
1 2 3 4 5 min 6
AMP
RTV
SQV NFV
IDVEOF
mAU (195nm)
Nguyen D.T., A. Zemann
J. Chromatogr. A, 922
(2001) 313 – 320
protease inhibitors
23. Caùc thuoác khaùng HIV
Nguyeãn Ñöùc Tuaán Ñaïi hoïc Y Döôïc TPHCM
0
4
8
1 2 3 4 5 6 7 8 min
285 nm
240 nm
195 nm
mAU
AMP
RTV
SQV
NFV
DLV ABC
NVP
3TC DDC
IDV
EOF
12
16
20
Capillary, L=42.5 cm, leff=34 cm,
i.d.=50 µm
Electrolyte, 16 mM H3PO4,
0.001% HDB, pH 2.2
Injection, 20 sec @ 10 mbar;
standard concentration, 5 ppm;
Separation, U=-30 kV
Detection, UV (bubble cell 200
µm).
AMP...amprenavir; RTV...ritonavir;
SQV...saquinavir; NFV...nelfinavir ;
IDV...indinavir
NVP...nevirapine; DLV...delavirdine;
ABC...abacavir; 3TC...lamivudine;
DDC...zalcitabine
D.T. Nguyen, A. Zemann
Journal of Chromatography A,
982 (2002) 153 – 161.
protease and reverse transcriptase inhibitors
24. Group 1: Chemical structure of CDs
• ACE inhibitors
Captopril
(CAP)
Enalapril
(ENA)
Lisinopril
(LI)
• Diuretics
Hydrochlorothiazide
(HCT)
Furosemide
(FURO)
NHS
COOH
CH3
O
H
N
N
O COOH
CH3
OOH3C
H
N
N
COOH
H2N
O
HOOC
N
H
S
NH
O O
H2N
S
O O
Cl
H2N
S
O O
COOH
N
H O
Cl
25. Group 1: ACE inhibitors and diuretics
• Optimized electrophoretic conditions
Electrophoretic conditions: 60 mM orate buffer at pH 8.6;
fused-silica capillary (57 cm x 50 m i.d., 48.5 cm); injection:
5s at 50 mbar; 18 kV; 25oC; detection wavelength: 214 nm
nm240 260 280 300 320 340
mAU
0
2
4
6
8
10
12
HCT
LI
ENA
FURO
CAP
26. Separation principle of MEKC
capillary wall
µEOF
µep+eof (A+)
= µep+eof (B-)
µep (A
+
)
µep (B-)
µmicelle
SDS
A+
C
µep(A+solub) µobs (A
+
)
µobs (B-)
µobs (C)
µobs (M)
0 1 2 3 4
C A+
EOF
B- M
5 6(t)
B-
28. Application – Multi-components
Conditions: Background electrolyte 10 mM borate, 10 mM phosphate, pH
9.2, 5% ACN, 50 mM SDS. Capillary 39.5/48 cm, 50 µm I.D. Temperature
25oC. Detection 210 nm. Applied voltage 20 kV. Injection 50 mbar x 20 sec
1
2
3
4
1. Paracetamol
2. Phenylpropanolamine
hydrochloride
3. Pseudoephedrine
hydrochloride (IS)
4. Chlorpheniramine
maleate
29. Group 2: Chemical structure of CDs
• Beta blockers
H2N
O
O
H3C
O
H
N CH3
CH3
OH
R
Atenolol
(ATE)
Metoprolol
(METO)
Propranolol
(PRO)
• Calcium channel antagonists
H
N CH3H3C
O
CH3
O
H3C
O
NO2
O
5
H
N
O
NH2
O CH3O
H3C
O
H3C
Cl
O
Amlodipine
(AM)
Nifedipine
(NI)
30. Group 2: -blockers and Ca channel antagonists
• Optimized electrophoretic conditions
Electrophoretic conditions: 10% methanol in 100 mM tris buffer at pH
12.0 containing 100 mM SDC; fused-silica capillary (57 cm x 50 m i.d.,
48.5 cm); injection: 5s at 50 mbar; 25 kV; 25oC; detection wavelength:
225 nm
nm240 260 280 300 320 340
mAU
0
2.5
5
7.5
10
12.5
15
17.5
20
(2)
ATE
METO
NI
PRO
AM
31. Group 3: Chemical structure of CDs
• Statin derivatives
Lovastatin
(LOV)
Simvastatin
(SIM)
Atorvastatin
(ATOR)
N O
OOHOH
F
. Ca 2+
, 3H2O
2
N
H
O
CH3
H3C
H
O
O
CH3
H
O
O
H3C
OH
CH3
H
H3C
O
OH
H
O
CH3
H3C
CH3
O
O
H
H3C
H
CH3
32. Group 3: Statin derivatives
• Optimized electrophoretic conditions
Electrophoretic conditions: 15% methanol in 15 mM borate buffer at
pH 8.0 containing 50 mM SDC; fused-silica capillary (57 cm x 50 m i.d.,
48.5 cm); injection: 5s at 50 mbar; 30 kV; 30oC; detection wavelength:
237 nm
nm240 260 280 300 320 340
mAU
0
2
4
6
8
10
ATOR
LOV
SIM
33. Application – Natural products
Analyte Additives Ref.
Flavonoid (rutin,
isoquercitrin, quercitrin,
kaempferol, quercetin, etc)
50 mM SDS P.G. Pietta, et al; J.
Chromatogr. (549) 367
Opium alkaloids (6 mixture) 12 mM SDS + 25
mM Tween 20
I. Bjornsdottir, et al; J.
Pharm. Biomed. Anal.
(13) 687
Amphetamines and related
substances
25 mM CTAB + 11%
DMSO + 1% ethanol
V.C. Trenerry, et al; J.
Chromatogr. A (708)
169
Cocaine and related
substances
50 mM CTAB +
7.5% ACN
V.C. Trenerry, et al;
Electrophoresis (15)
103
Codeine and its by products 40 mM SDS M. Korman, et al; J.
Chromatogr. (645) 366
34. Application – Optical purity testing of drugs
• Use area percentage method for purity testing
of drugs as in HPLC
• Normalize peak areas with migration times
• Identify impurities above apparent levels of
0.1%
35. Application – Dexchlorpheniramine maleate
min.
2.5 5 7.5 10 12.5 15 17.5
mAU
0
2
4
6
8
10
12
14
18,393
14,469
17,994
1
2
3
Optical purity testing of dexchlorpheniramine
maleate by CE with -CD
Conditions: Capillary: 76.5 cm (68 cm effective length) x 50 m I.D.;
Background electrolyte: 0.05 M Tris buffer pH 3.5 + 5 mM -CD; Detection: 214
nm; Applied voltage: 20 kV; Injection: 50 mbar x 10 sec.; Temperature: 25oC.
1. Pseudoephedrine HCl (IS)
2. Levochlorpheniramine maleate
3. Dexchlorpheniramine maleate
36. Chemical structure of drug substances
Nefopam
NCH3
O
*
1
5
O N CH3
CH3
1
2
3
*
OH
Propranolol
*
Brompheniramine
Ketoconazole
N ON
CH3
O
O
O
N
N
Cl Cl
* *
1
2
3
4
5
Miconazole
Cl Cl
O
Cl Cl
N
N
*
1
2
2''
2'
4''4'
N
O
NH2
COOCH2CH3
Cl
CH3
CH3OOC
1
3
4
5
6
2
3
4
6
1
*
5
2
Amlodipine
Ofloxacin
N
O
N
N
CH3 CH3
OH
F
O O
1
2
*
3
4
5
6
78
10
9
Promethazine
S
N
N
CH3 CH3
CH3
*1
10
2
37. Effect of the CD types and their concentrations on Rs
Electrophoretic conditions: 50 – 100 mM tris-phosphate buffer pH 2.5
– 3.0, 20% methanol (for propranolol) or 25% acetonitrile (for
nefopam); capillary (63.5 cm x 50 m i.d., 54 cm); = max of each
compound; 25oC; 20 kV; injection: 5s at 50 mbar.
Rs
38. Electropherograms for the chiral separation of enantiomers
Optimized electrophoretic conditions: 50 mM tris-phosphate buffer pH
2.5; capillary (63.5 cm x 50 m i.d., 54 cm); = 228 nm, 25oC; 20
kV; injection: 5s at 50 mbar.
Miconazole
5 10 15
0
1
2
3
4
5
6
min.
mAU
2 mM
-CD
min.
5 10 15
0
1
2
3
4
5
6
mAU7
2 mM HP-
-CD
5 10 15
0
1
2
3
4
5
6
min.
mAU
2 mM HB-
-CD
39. Electropherograms for the chiral separation of enantiomers
Optimized electrophoretic conditions: 50 mM tris-phosphate buffer pH
3.5; capillary (63.5 cm x 50 m i.d., 54 cm); = 230 nm, 25oC; 20
kV; injection: 5s at 50 mbar.
Brompheniramine
10 mM -
CD
25 mM HP-
-CD
15 mM HB-
-CD
40. Electropherograms for the chiral separation of enantiomers
Optimized electrophoretic conditions: 50 mM tris-phosphate buffer pH
2.5, 25% MeCN; capillary (63.5 cm x 50 m i.d., 54 cm); = 275 nm,
25oC; 20 kV; injection: 5s at 50 mbar.
Nefopam
30 mM
-CD
30 mM
HP--CD
20 mM
HB--CD
41. Electropherograms for the chiral separation of enantiomers
Optimized electrophoretic
conditions:
50 mM tris-phosphate buffer pH
2.5; capillary (63.5 cm x 50 m
i.d., 54 cm); = 360 nm, 25oC;
20 kV; injection: 5s at 50 mbar.
Amlodipine
min
.
5 10 15 20 25
mAU
7
1
3
5
0
2
4
6
8
10 mM
HP--
CD
5 mM
HB--
CD
min.
5 10 15 20 25
mAU
0
2
4
6
8
Ofloxacin
Optimized electrophoretic
conditions:
50 mM tris-phosphate buffer pH
2.5; capillary (63.5 cm x 50 m
i.d., 54 cm); = 294 nm, 25oC;
20 kV; injection: 5s at 50 mbar.
5 10 15 20 25
min.
0
2
4
6
8
10 mAU
30 mM
HP--
CD
5 10 15 20
mAU
0
2
4
6
8
min.
30 mM
HB--CD
42. Electropherograms for the chiral separation of enantiomers
Optimized electrophoretic
conditions:
50 mM tris-phosphate buffer pH
2.5, 20% MeOH; capillary (63.5
cm x 50 m i.d., 54 cm); = 288
nm, 25oC; 20 kV; injection: 5s at
50 mbar.
Propranolol Ketoconazole Promethazine
Optimized electrophoretic
conditions:
Tris-phosphate; 63.5 cm x 50 m
i.d., 54 cm; 25oC; 20 kV; injection:
5s at 50 mbar. KET: 50 mM BGE pH
3.0; = 227 nm. PRM: 100 mM
BGE pH 2.5, 30% MeOH; = 254
10 20 30 40
0
2
4
6
8
mAU
min
.
30 mM
HP--
CD
min.
20 30 40
0
2
4
6
8
mAU
10
20 mM
HB--CD
5 10 15 20
min.
mAU
0
2
4
8
6
10
15 mM
HB--CD
5 15 25 35
min.
0
2
4
6
8
mAU
30 mM
HB--CD
43. Application
105 15 20 25
min.
mAU
0
2
4
6
8
R-amlodipine
S-amlodipine
Electrophoretic conditions: 50 mM tris-phosphate buffer pH 2.5, 10 mM
HP--CD; capillary (63.5 cm x 50 m i.d., 54 cm); = 360 nm, 25oC;
20 kV; injection: 5s at 50 mbar.
min
.
5 15 25
mAU
0
10
20
30
S-amlodipine
R-amlodipine
min.
5 10 15 20
mAU
-5
0
5
10
S-amlodipine
Amlodipine racemic
spiked R-amlodipine
S-amlodipine drug
substance
S-amlodipine tablet
44. Application
Electrophoretic conditions: 50 mM tris-phosphate buffer pH 2.5, 30 mM
HB--CD; capillary (63.5 cm x 50 m i.d., 54 cm); = 294 nm, 25oC;
20 kV; injection: 5s at 50 mbar.
Ofloxacin racemic
spiked levofloxacin
Levofloxacin tablet
min.5 10 15 20
mAU
0
4
8
12
16
Levofloxacin
Ofloxacin
min.5 10 15 20
mAU
0
4
8
12
16
Levofloxacin
45. Conclusion
CZE and MEKC can be used for
drug analysis as a complementary
or alternative method to HPLC
46. Conclusion
Advantage
• One-run separation of every kind of drug, including
cationic, neutral and anionic is possible within a
relatively short time
• MEKC is especially powerful for the separation of
complex mixtures because of its high resolution
• Direct enantiomer separation also can be successful
using chiral selectors
Disadvantage
• For much wider use it is still desirable for the
precision in quantitative analysis to be improved to
be comparable to those in HPLC