Sains Malaysiana 49(11)(2020): 2699-2714
http://dx.doi.org/10.17576/jsm-2020-4911-09
Enantiomeric
Separation of Azole Antifungal Compounds using Chromatographic and
Electrophoretic Techniques: A Mini Review
(Pemisahan Enantiomerik Sebatian Antikulat Azol menggunakan Teknik Kromatografi dan Elektroforetik: Suatu Ulasan Mini)
NURUL RAIHANA BINTI AZHARI1, BOON YIH HUI1, NUR
NADHIRAH MOHAMAD ZAIN1, FAIZ BUKHARI MOHD SUAH2,
SHARIFAH MOHAMAD3,4, NOORFATIMAH YAHAYA1*
& MUGGUNDHA RAOOV3,4*
1Integrative Medicine Cluster, Advanced Medical and Dental
Institute (AMDI), Universiti Sains Malaysia, 13200 Penang, Malaysia
2School of Chemical Sciences, Universiti Sains Malaysia, 11800
Penang, Malaysia
3Department of Chemistry, Faculty of Science, University of
Malaya, 50603 Kuala Lumpur, Malaysia
4University of Malaya Centre for Ionic Liquids, Department of
Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
Received: 19 March 2020/Accepted:
12 May 2020
Abstract
The separation of azole antifungal chiral compounds
has gaining much interests since 1980’s as they possess different biological,
pharmaceutical, and pharmacokinetic behaviors at various toxicity levels.
Numerous studies have looked into this subject matter, and therefore, this
review presents an overview on different chiral separation techniques that have
been developed such as liquid chromatography (LC), gas chromatography (GC),
supercritical fluid chromatography (SFC), and capillary electrophoresis (CE).
This comprehensive review also discusses the mechanisms of the developed
analytical methods such as preparation techniques and optimization parameters
towards the enantioseparation performances as well as
their advantages and drawbacks. Lastly, the conclusion and future directions of
the chiral separation, particularly for azole compounds are provided
accordingly.
Keywords: Antifungal compounds; azole; capillary
electrophoresis; chiral separation; chromatographic analysis
Abstrak
Pemisahan sebatian kiral antikulat azol telah menarik perhatian sejak tahun 1980 kerana ia mempunyai sifat biologi, farmaseutik dan farmakokinetik pada tahap ketoksikan yang berbeza. Oleh itu, kajian ini membentangkan gambaran keseluruhan mengenai teknik pemisahan kiral yang berbeza seperti kromatografi cecair (LC), kromatografi gas
(GC), kromatografi cecair supergentingan (SFC) dan elektroforesis rerambut (CE). Kajian komprehensif ini juga membincangkan mekanisme bagi kaedah analisis yang maju seperti teknik penyediaan dan parameter pengoptimuman ke arah persembahan pemisahan enantio serta kelebihan dan kekurangannya. Akhir sekali, kesimpulan dan hala tuju masa depan dalam pemisahan kiral, terutamanya bagi sebatian azol diberikan dengan sewajarnya.
Kata kunci: Analisis kromatografik; azol; pemisahan kiral; rerambut elektroforesis
; sebatian antikulat
REFERENCES
Aboul-Enein, H.Y. & Ali, I.
2004. Applications of polysaccharide-based chiral stationary phases for
resolution of different compound classes. In Chiral Separations: Methods in Molecular Biology, edited by Gübitz, G. & Schmid, M.G. New Jersey: Humana Press.
vol. 243. pp. 183-196.
Aboul-Enein, H.Y. & Ali, I. 2002. Comparative study
of the enantiomeric resolution of chiral antifungal drugs econazole, miconazole
and sulconazole by HPLC on various cellulose chiral columns in normal phase
mode. Journal of Pharmaceutical and Biomedical Analysis 27(3-4):
441-446.
Aboul-Enein, H.Y. & Ali, I. 2001. Comparison of the
chiral resolution of econazole, miconazole, and sulconazole by HPLC using
normal-phase amylose CSPs. Fresenius' Journal of Analytical Chemistry 370(7): 951-955.
Aboul-Enein, H.Y. & Bakr, S.A. 1998. Enantiomeric
resolution of propranolol and analogs on two cellulose (Chiralcel OF and OC)
and one amylose (Chiralpak AD) chiral stationary phases. Journal of Liquid
Chromatography & Related Technologies 21(8): 1137-1145.
Alagar, R.M., Bhargav, K.S., Banji, D. & Selva, K.D.
2014. Updated review on micellar electro kinetic chromatography. Journal of
Chromatography and Separation Techniques 5: 1-6.
Ali, I., Aboul-Enein, H.Y., Gaitonde, V.D., Singh, P.,
Rawat, M.S.M. & Sharma, B. 2009. Chiral separations of imidazole antifungal
drugs on amycoat RP column in HPLC. Chromatographia 70(1-2): 223-227.
Andrade, R.T., da Silva, R.C.S., Pereira, A.C. &
Borges, K.B. 2015. Self-assembly pipette tip-based cigarette filters for
micro-solid phase extraction of ketoconazole cis-enantiomers in urine samples
followed by high-performance liquid chromatography/diode array detection. Analytical
Methods 7(17): 7270-7279.
Anwar-Mohamed, A., El-Sherbeni, A.A., Hamdy, D.A.,
Korashy, H.M., Brocks, D.R. & El-Kadi, A. O. 2016. Ketoconazole
stereoisomers differentially induce cytochrome P450 1A1 between human hepatoma
HepG2 and mouse hepatoma Hepa1c1c7 cells. Journal of Pharmaceutical Sciences 105: 1318-1326.
Aperis, G. & Mylonakis, E. 2006. Newer triazole
antifungal agents: Pharmacology, spectrum, clinical efficacy and limitations. Expert
Opinion on Investigational Drugs 15(6): 579-602.
Armstrong, D.W. 1984. Chiral stationary phases for high
performance liquid chromatographic separation of enantiomers: A mini-review. Journal
of Liquid Chromatography 7(S2): 353-376.
Benfield, P. & Stephen, P. 1988. Sulconazole. Drugs 35(2): 143-153.
Bernal, J.L., Toribio, L., Del Nozal, M.J., Nieto, E.M.
& Montequi, M.I. 2002. Separation of antifungal chiral drugs by SFC and
HPLC: A comparative study. Journal of Biochemical and Biophysical Methods 54(1-3): 245-254.
Bernal, J.L., Del Nozal, M.J., Toribio, L., Montequi,
M.I. & Nieto, E.M. 2000. Separation of ketoconazole enantiomers by chiral
subcritical-fluid cromatography. Journal of Biochemical and Biophysical
Methods 43(1-3): 241-250.
Bhanderi, B.B., Yadav, M.M. & Roy, A. 2009.
Antifungal drug resistance - concerns for veterinarians. Veterinary World 2(5): 204-207.
Bi, C., Zhao, E., Liu, Y., Qiu, J. & Zhou, Z. 2006.
Direct optical resolution of chiral pesticides by HPLC on emamectin CSP under
normal phase conditions. Journal of Liquid Chromatography and Related
Technologies 29(11): 1601-1607.
Bicchi, C., Cravotto, G., D'amato, A., Rubiolo, P.,
Galli, A. & Galli, M. 1999. Cyclodextrin derivatives in gas chromatographic
separation of racemates with different volatility. part XV:
6-o-t-Butyldimethylsilyl-versus 6-o-t-Hexyldimethylsilyl-β and -γ
Derivatives. Journal of Microcolumn Separations 11(7): 487-500.
Bounoua, N., Sekkoum, K., Belboukhari, N., Cheriti, A.
& Aboul-Enein, H.Y. 2016. Achiral and chiral separation and analysis of
antifungal drugs by HPLC and CE: A comparative study: Mini review. Journal
of Liquid Chromatography & Related Technologies 39(11): 513-519.
Brauer,
V.S., Rezende, C.P., Pessoni, A.M., De Paula, R.G., Rangappa, K.S., Nayaka,
S.C., Gupta, V.K. & Almeida, F. 2019. Antifungal agents in agriculture:
Friends and foes of public health. Biomolecules 9(10): 521.
Burden, R.S., Deas, A.H. & Clark, T. 1987.
Separation of enantiomers of fungicidal and plant growth regulatory triazole
alcohols using chiral derivatisation and capillary gas chromatography. Journal
of Chromatography A 391: 273-279.
Cai, X.J., Xu, X.Z. & Pan, C.X. 2005. Study of
optical isomer separation of chiral antifungal drugs tetramisole, miconazole,
and paclobutrazol on two chiral stationary phases. Analytical Letters 38(7): 1149-1157.
Castro‐Puyana, M., Crego, A.L., Marina, M.L. &
García‐Ruiz, C. 2007. Enantioselective separation of azole compounds by
EKC. Reversal of migration order of enantiomers with CD concentration. Electrophoresis 28(15): 2667-2674.
Castro‐Puyana, M., Crego, A.L. & Marina, M.L.
2006. Separation and quantitation of the four stereoisomers of itraconazole in
pharmaceutical formulations by electrokinetic chromatography. Electrophoresis 27(4): 887-895.
Castro‐Puyana, M., Crego, A.L. & Marina, M.L.
2005. Enantiomeric separation of ketoconazole and terconazole antifungals by electrokinetic
chromatography: Rapid quantitative analysis of ketoconazole in pharmaceutical
formulations. Electrophoresis 26(20): 3960-3968.
Chankvetadze, B., Endresz, G. & Blaschke, G. 1995.
Enantiomeric resolution of chiral imidazole derivatives using capillary
electrophoresis with cyclodextrin-type buffer modifiers. Journal of
Chromatography A 700(1-2): 43-49.
Cheng, Y., Dong, F., Liu, X., Xu, J., Li, J., Chen, X.,
Li, Y., Wu, X. & Zheng, Y., 2013. Stereoselective separation and
determination of the triazole fungicide propiconazole in water, soil and grape
by normal phase HPLC. Analytical Methods 5(3): 755-761.
Cirilli, R., Costi, R., Di Santo, R., Ferretti, R., La
Torre, F., Angiolella, L. & Micocci, M. 2002. Analytical and
semipreparative enantiomeric separation of azole antifungal agents by
high-performance liquid chromatography on polysaccharide-based chiral
stationary phases: Application to in
vitro biological studies. Journal of Chromatography A 942(1-2):
107-114.
Como, J.A. & Dismukes, W.E. 1994. Oral azole drugs
as systemic antifungal therapy. New England Journal of Medicine 330(4):
263-272.
Crego, A.L., Marina, M.L. & Lavandera, J.L. 2001.
Optimization of the separation of a group of antifungals by capillary zone
electrophoresis. Journal of Chromatography A 917(1-2): 337-345.
Del Nozal, M.J., Toribio, L., Bernal, J.L. &
Castano, N. 2003. Separation of triadimefon and triadimenol enantiomers and
diastereoisomers by supercritical fluid chromatography. Journal of Chromatography
A 986(1): 135-141.
Dilmaghanian, S., Gerber, J.G., Filler, S.G., Sanchez,
A. & Gal, J. 2004. Enantioselectivity of inhibition of cytochrome P450 3A4
(CYP3A4) by ketoconazole: Testosterone and methadone as substrates. Chirality:
The Pharmacological, Biological, and Chemical Consequences of Molecular
Asymmetry 16(2): 79-85.
Dong, F., Li, J., Chankvetadze, B., Cheng, Y., Xu, J.,
Liu, X., Li, Y., Chen, X., Bertucci, C., Tedesco, D. & Zanasi, R. 2013.
Chiral triazole fungicide difenoconazole: Absolute stereochemistry,
stereoselective bioactivity, aquatic toxicity, and environmental behavior in
vegetables and soil. Environmental Science & Technology 47(7):
3386-3394.
Dong, Y., Ren, X., Huang, A., Sun, Y. & Sun, Z.
1998. Chiral separation of bencynonate and econazole by cyclodextrin-modified
capillary zone electrophoresis. HRC. Journal of High Resolution
Chromatography 21(7): 421-423.
Eeckhaut, A. & Michotte, Y. 2006. Chiral separations
by capillary electrophoresis: Recent developments and applications. Electrophoresis 27(14): 2880-2895.
Ferguson, P.D., Goodall, D.M. & Loran, J.S. 1996.
Systematic approach to the treatment of enantiomeric separations in capillary
electrophoresis and liquid chromatography III. A binding constant-retention
factor relationship and effects of acetonitrile on the chiral separation of
tioconazole. Journal of Chromatography A 745(1-2): 25-35.
Gala, D., DiBenedetto, D.J., Mergelsberg, I., Kugelman,
M. & Research, S.P. 1996. Total chiral synthesis of azole antifungals via
α-hydroxylation of ketones. Tetrahedron Letters 37(45): 8117-8120.
Garrison, A.W., Avants, J.K. & Miller, R.D. 2011.
Loss of propiconazole and its four stereoisomers from the water phase of two
soil-water slurries as measured by capillary electrophoresis. International
Journal of Environmental Research and Public Health 8(8): 3453-3467.
Ghanem, A., Hoenen, H. & Aboul-Enein, H.Y. 2006.
Application and comparison of immobilized and coated amylose tris-(3,
5-dimethylphenylcarbamate) chiral stationary phases for the enantioselective
separation of β-blockers enantiomers by liquid chromatography. Talanta 68(3): 602-609.
Ghannoum, M.A. & Rice, L.B. 1999. Antifungal agents:
Mode of action, mechanisms of resistance, and correlation of these mechanisms
with bacterial resistance. Clinical Microbiology Reviews 12(4): 501-517.
Girmenia, C. 2009. New generation azole antifungals in
clinical investigation. Expert Opinion on Investigational Drugs 18(9):
1279-1295.
Gübitz, G. 1990. Separation of drug enantiomers by HPLC
using chiral stationary phases - A selective review. Chromatographia 30(9-10): 555-564.
Gübitz, G. & Schmid, M.G. 2008. Chiral separation by
capillary electromigration techniques. Journal of Chromatography A 1204(2): 140-156.
Hamdy, D.A. & Brocks, D.R. 2008. A stereospecific
high‐performance liquid chromatographic assay for the determination of
ketoconazole enantiomers in rat plasma. Biomedical Chromatography 22(5):
542-547.
Hermawan, D., Ibrahim, W.A.W., Sanagi, M.M. &
Aboul-Enein, H.Y. 2010. Chiral separation of econazole using micellar
electrokinetic chromatography with hydroxypropyl-γ-cyclodextrin. Journal
of Pharmaceutical and Biomedical Analysis 53(5): 1244-1249.
Hiroyuki, N. & Terabe, S. 1996. Micellar
electrokinetic chromatography perspectives in drug analysis. Journal of
Chromatography A 735(1-2): 3-27.
Huang, Q., Zhang, K., Wang, Z., Wang, C. & Peng, X.
2012. Enantiomeric determination of azole antifungals in wastewater and sludge
by liquid chromatography–tandem mass spectrometry. Analytical and
Bioanalytical Chemistry 403(6): 1751-1760.
Ilisz, I., Berkecz, R. & Péter, A. 2008. Application
of chiral derivatizing agents in the high-performance liquid chromatographic
separation of amino acid enantiomers: A review. Journal of Pharmaceutical
and Biomedical Analysis 47(1): 1-15.
Ilisz, I., Berkecz, R. & Péter, A. 2006. HPLC
separation of amino acid enantiomers and small peptides on macrocyclic
antibiotic‐based chiral stationary phases: A review. Journal of
Separation Science 29(10): 1305-1321.
Kim, H., Radwanski, E., Lovey, R., Lin, C.C. &
Nomeir, A.A. 2002. Pharmacokinetics of the active antifungal enantiomer, SCH
42427 (RR), and evaluation of its chiral inversion in animals following its
oral administration and the oral administration of its racemate genaconazole
(RR/SS). Chirality: The Pharmacological, Biological, and Chemical
Consequences of Molecular Asymmetry 14(5): 436-441.
Kodama, S., Yamamoto, A., Ohura, T., Matsunaga, A. &
Kanbe, T. 2003. Enantioseparation of imazalil residue in orange by capillary
electrophoresis with 2-hydroxypropyl-β-cyclodextrin as a chiral selector. Journal
of Agricultural and Food Chemistry 51(21): 6128-6131.
Lämmerhofer, M. 2010. Chiral recognition by
enantioselective liquid chromatography: Mechanisms and modern chiral stationary
phases. Journal of Chromatography A 1217(6): 814-856.
Li, J., Dong, F., Xu, J., Liu, X., Li, Y., Shan, W.
& Zheng, Y. 2011. Enantioselective determination of triazole fungicide
simeconazole in vegetables, fruits, and cereals using modified QuEChERS (quick,
easy, cheap, effective, rugged and safe) coupled to gas chromatography/tandem
mass spectrometry. Analytica Chimica Acta 702(1): 127-135.
Li, Y., Dong, F., Liu, X., Xu, J., Li, J., Kong, Z.,
Chen, X., Liang, X. & Zheng, Y. 2012. Simultaneous enantioselective
determination of triazole fungicides in soil and water by chiral liquid
chromatography/tandem mass spectrometry. Journal of Chromatography A 1224: 51-60.
Lin, X., Zhu, C. & Hao, A. 2004. Evaluation of newly
synthesized derivative of cyclodextrin for the capillary electrophoretic
separation. Journal of Chromatography A 1059(1-2): 181-189.
Lv, C. & Zhou, Z. 2011. Chiral HPLC separation and
absolute configuration assignment of a series of new triazole compounds. Journal
of Separation Science 34(4): 363-370.
Maertens, J.A. 2004. History of the development of azole
derivatives. Clinical Microbiology and Infection 10: 1-10.
Mangelings, D. & Vander Heyden, Y. 2008. Chiral
separations in sub‐and supercritical fluid chromatography. Journal of
Separation Science 31(8): 1252-1273.
Mskhiladze, A., Karchkhadze, M., Dadianidze, A., Fanali,
S., Farkas, T. & Chankvetadze, B. 2013. Enantioseparation of chiral
antimycotic drugs by HPLC with polysaccharide-based chiral columns and polar
organic mobile phases with emphasis on enantiomer elution order. Chromatographia 76(21-22): 1449-1458.
Nagarjuna, A., Reddy, K.P., Mukkanti, K. &
Suryanarayana, M.V. 2007. A validated LC method for separation and
quantification of voriconazole and its enantiomer. Chromatographia 66(5-6):
439-441.
Nishi, H. 1996. Enantiomer separation of drugs by
electrokinetic chromatography. Journal of Chromatography A 735(1-2):
57-76.
Nishi, H. & Terabe, S. 1995. Optical resolution of
drugs by capillary electrophoretic techniques. Journal of Chromatography A 694(1) 245-276.
Okamoto, Y. & Kaida, Y. 1994. Resolution by
high-performance liquid chromatography using polysaccharide carbamates and
benzoates as chiral stationary phases. Journal of Chromatography A 666(1-2):
403-419.
Osbourn, D.M., Weiss, D.J. & Lunte, C.E. 2000.
On‐line preconcentration methods for capillary electrophoresis. ELECTROPHORESIS:
An International Journal 21(14): 2768-2779.
Otsuka, K. & Terabe, S. 2000. Enantiomer separation
of drugs by micellar electrokinetic chromatography using chiral surfactants. Journal
of Chromatography A 875(1-2): 163-178.
Pan, C.X., Shen, B.C., Xu, B.J., Chen, J.J. & Xu,
X.Z. 2006. Comparative enantioseparation of seven triazole fungicides on (S,
S)‐Whelk O1 and four different cellulose derivative columns. Journal
of Separation Science 29(13): 2004-2011.
Pérez-Fernández, V., García, M.Á. & Marina, M.L.
2011. Chiral separation of agricultural fungicides. Journal of
Chromatography A 1218(38): 6561-6582.
Quaglia, M.G., Donati, E., Desideri, N., Fanali, S.,
D'auria, F.D. & Tecca, M. 2002. Chiral discrimination by HPLC and CE and
antifungal activity of racemic fenticonazole and its enantiomers. Chirality:
The Pharmacological, Biological, and Chemical Consequences of Molecular
Asymmetry 14(5): 449-454.
Quirino, J.P. & Terabe, S. 1999. Electrokinetic
chromatography. Journal of Chromatography A 856(1-2): 465-482.
Saito, K., Yato, M., Ito, T., Iwasaki, Y., Ito, R.,
Matsuki, Y. & Nakazawa, H. 2008. Verification of the need for optical
purity measurement of chiral pesticide standards as agricultural reference
materials. Accreditation and Quality Assurance 13(7): 373-379.
Scorzoni,
L., de Paula e Silva, A.C., Marcos, C.M., Assato, P.A., de Melo, W.C., de
Oliveira, H.C., Costa-Orlandi, C.B., Mendes-Giannini, M.J. & Fusco-Almeida,
A.M. 2017. Antifungal therapy: New advances in the understanding and treatment
of mycosis. Frontiers in Microbiology 8: 36.
Sellergren, B. 2001. Imprinted chiral stationary phases
in high-performance liquid chromatography. Journal of Chromatography A 906(1-2): 227-252.
Shalini,
K., Kumar, N., Drabu, S. & Sharma, P.K. 2011. Advances in synthetic
approach to and antifungal activity of triazoles. Beilstein Journal of
Organic Chemistry 7(1): 668-677.
Suedee, R., Saelim, J., Thavornpibulbut, T. &
Srichana, T. 1999. Chiral determination of various adrenergic drugs by
thin-layer chromatography using molecularly imprinted chiral stationary phases
prepared with α-agonists. Analyst 124(7): 1003-1009.
Tachibana, K. & Ohnishi, A. 2001. Reversed-phase
liquid chromatographic separation of enantiomers on polysaccharide type chiral
stationary phases. Journal of Chromatography A 906(1-2): 127-154.
Terabe, S., Otsuka, K., Ichikawa, K., Tsuchiya, A. &
Ando, T. 1984. Electrokinetic separations with micellar solutions and
open-tubular capillaries. Analytical Chemistry 56(1): 111-113.
Thienpont, A., Gal, J., Aeschlimann, C. & Felix, G.
1999. Studies on stereoselective separations of the" azole'' antifungal
drugs ketoconazole and itraconazole using HPLC and SFC on silica-based
polysaccharides. Analusis 27(8): 713-718.
Toribio, L., Bernal, J.L., Martín, M.T., Bernal, J.
& Del Nozal, M.J. 2014. Effects of organic modifier and temperature on the
enantiomeric separation of several azole drugs using supercritical fluid
chromatography and the Chiralpak AD column. Biomedical Chromatography 28(1) 152-158.
Toribio, L., del Nozal, M.J., Bernal, J.L., Alonso, C.
& Jiménez, J.J. 2007. Enantiomeric separation of several antimycotic azole
drugs using supercritical fluid chromatography. Journal of Chromatography A 1144(2): 255-261.
Toribio, L., Del Nozal, M.J., Bernal, J.L., Jiménez,
J.J. & Alonso, C. 2004. Chiral separation of some triazole pesticides by
supercritical fluid chromatography. Journal of Chromatography A 1046(1-2): 249-253.
Wan Ibrahim, W.A., Arsad, S.R., Maarof, H., Sanagi, M.M.
& Aboul‐Enein, H.Y. 2015. Chiral separation of four stereoisomers of
ketoconazole drugs using capillary electrophoresis. Chirality 27(3):
223-227.
Wan Ibrahim, W.A., Arsad, S.R., Maarof, H. & Sanagi,
M.M. 2014. Experimental and theoretical study on chiral recognition mechanism
of ketoconazole enantiomers using heptakis (2, 3,
6-tri-O-methyl)-β-cyclodextrin. Malaysian Journal of Fundamental and
Applied Sciences 10: 2.
Wan Ibrahim, W.A., Abd Wahib, S.M., Hermawan, D.,
Sanagi, M.M. & Aboul‐Enein, H.Y. 2013. Separation of selected
imidazole enantiomers using dual cyclodextrin system in micellar electrokinetic
chromatography. Chirality 25(6): 328-335.
Wan Ibrahim, W.A., Hermawan, D., Sanagi, M.M. &
Aboul-Enein, H.Y. 2010. Stacking and sweeping in cyclodextrin-modified MEKC for
chiral separation of hexaconazole, penconazole and myclobutanil. Chromatographia 71(3-4): 305-309.
Wan Ibrahim, W.A., Hermawan, D., Sanagi, M.M. &
Aboul‐Enein, H.Y. 2009a. Cyclodextrin‐modified MEKC for
enantioseparation of hexaconazole, penconazole, and myclobutanil. Journal of
Separation Science 32(3): 466-471.
Wan Ibrahim, W.A., Warno, S.A., Aboul‐Enein, H.Y.,
Hermawan, D. & Sanagi, M.M. 2009b. Simultaneous enantioseparation of
cyproconazole, bromuconazole, and diniconazole enantiomers by CD‐modified
MEKC. Electrophoresis 30(11): 1976-1982.
Wang, P., Liu, D., Jiang, S., Xu, Y. & Zhou, Z.
2008. The chiral separation of triazole pesticides enantiomers by amylose-tris
(3, 5-dimethylphenylcarbamate) chiral stationary phase. Journal of
Chromatographic Science 46(9): 787-792.
Wang, P., Jiang, S., Liu, D., Wang, P. & Zhou, Z.
2005. Direct enantiomeric resolutions of chiral triazole pesticides by
high-performance liquid chromatography. Journal of Biochemical and
Biophysical Methods 62(3): 219-230.
Wei, Y., Li, J., Zhu, C., Hao, A. & Zhao, M. 2005.
2-O-(2-hydroxybutyl)-β-cyclodextrin as a chiral selector for the capillary
electrophoretic separation of chiral drugs. Analytical Sciences 21(8):
959-962.
Woolley, D.W. 1944. Some biological effects produced by
benzimidazole and their reversal by purines. Journal of Biological Chemistry 152(2): 225-232.
Wu, Y.S., Lee, H.K. & Li, S.F.Y. 2001.
High-performance chiral separation of fourteen triazole fungicides by sulfated
β-cyclodextrin-mediated capillary electrophoresis. Journal of
Chromatography A 912(1): 171-179.
Yamamoto, C. & Okamoto, Y. 2004. Chiral separation
by HPLC using polysaccharide-based chiral stationary phases. In Chiral Separations: Methods in Molecular Biology, edited by Gübitz, G. & Schmid, M.G. New Jersey: Humana Press.
vol. 243. pp. 173-181.
Yashima, E. 2001. Polysaccharide-based chiral stationary
phases for high-performance liquid chromatographic enantioseparation. Journal
of Chromatography A 906(1-2): 105-125.
Ye, J., Wu, J. & Liu, W. 2009. Enantioselective
separation and analysis of chiral pesticides by high-performance liquid
chromatography. TrAC Trends in Analytical Chemistry 28(10): 1148-1163.
Zhang, H., Qian, M., Wang, X., Wang, X., Xu, H., Wang,
Q. & Wang, M. 2012. HPLC-MS/MS enantioseparation of triazole fungicides
using polysaccharide‐based stationary phases. Journal of Separation
Science 35(7): 773-777.
Zhao, M., Cui, Y., Yu, J., Xu, S. & Guo, X. 2014.
Combined use of hydroxypropyl‐β‐cyclodextrin and ionic liquids
for the simultaneous enantioseparation of four azole antifungals by CE and a
study of the synergistic effect. Journal of Separation Science 37(1-2):
151-157.
Zhou, Z., Li, X., Chen, X. & Hao, X. 2010. Synthesis
of ionic liquids functionalized β-cyclodextrin-bonded chiral stationary
phases and their applications in high-performance liquid chromatography. Analytica
Chimica Acta 678(2): 208-214.
*Corresponding author; email: noorfatimah@usm.my
|