Separation of Ceftibuten Stereo Isomers With 100% Aqueous Mo
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Transcript of Separation of Ceftibuten Stereo Isomers With 100% Aqueous Mo
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7/28/2019 Separation of Ceftibuten Stereo Isomers With 100% Aqueous Mo
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Ceftibuten dihydrate is currently one of the safest antimicrobial agents availableto clinicians. As a result, it is one of the most frequently prescribed antibiotics.Ceftibuten belongs to the third generation of cephalosporin antibiotics (cephems),which are used to treat many varieties of infections caused by gram-positive andnegative bacteria. Ceftibuten has two stereo isomers, the (Z) and the (E) isomers.
Most HPLC solvents are considered hazardous to health and to the environment.Safe usage and disposal of large volumes of such solvents has always posedproblems. Availability of columns, such as Zorbax SB-Aq, that can be used underhigh aqueous conditions and still retain consistent retention, resolution, selec-tivity, and peak shape is a great step in reducing the environmental impact ofthese solvents. Attempts to separate ceftibuten isomers on C18 columns withlow percentages of organic modifiers (2%) did not give good resolution and peakshape (Figure 1). However, separation of ceftibuten isomers was achieved with100% aqueous mobile phases on Zorbax SB-Aq column (Figure 2). Ceftibutenalso exhibited very good linearity and a low limit of detection (LOD) (Figure 3).
Separation of Ceftibuten Stereo Isomerswith 100% Aqueous Mobile Phase UsingZorbax SB-AqApplication
Drug Development
Adebayo O. Onigbinde
Highlights
The Zorbax SB-Aq column has analkyl bonded phase designed toeliminate phase collapse and still
retain both hydrophilic and othercompounds, when using highlyaqueous mobile phases, including100% water.
Methods that require ion-pairingreagents for retention on other C8or C18 bonded phases can oftenbe carried out on the ZorbaxSB-Aq column without ion-pairingreagents or organic modifiers.
The Zorbax SB-Aq column sepa-rated ceftibuten stereo isomerswith good peak shape and resolu-
tion in 100% aqueous phase with-out the use of ion-pairing agentsor organic modifiers.
The Zorbax SB-Aq column candeliver unique selectivity and res-olution with very good peak shapefor polar analytes that require lowlevels of organic modifier foradequate retention.
The Zorbax SB-Aq column resolvescompounds at a concentrationcommonly encountered in phar-macokinetic studies (Ceftibuten,LOD = 1.5 ng).Figure 1. Separation of ceftibuten isomers on C-18 columns with low percentages of
organic modifiers. Concentration of ceftibuten dihydrate: 3.0 mg/mL.
Experimental Conditions
Instrument: Agilent 1100 Series HPLC; Temp: ambient; Column: Alkyl-C18,4.6 150 mm, 5 m; Mobile phase: 2% ACN, 98% 10 mM ammonium acetate,pH 5.4; Flow rate: 1 mL/min; Injection volume: 5 L; Diode array detector:254 nm; Reference: 400 nm; Bandwidth: 100 nm
min0 1 2 3 4 5 6 7 8 9
mAU
0
50
100
150
200
250
300
DAD1 A, Sig = 254,100 Ref = 400,100 (71102C\001-0201.D)
1.
0641.
151
1.2
3
0
1.
371
2.
578
5.
015
Z-CeftibutenExcipent
E-Ceftibuten
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7/28/2019 Separation of Ceftibuten Stereo Isomers With 100% Aqueous Mo
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Agilent shall not be liable for errors contained herein or
for incidental or consequential damages in connection
with the furnishing, performance, or use of this
material.
Information, descriptions, and specifications in this
publication are subject to change without notice.
Agilent Technologies, Inc. 2002
Printed in the USA
September 18, 2002
5988-7625EN
www.agilent.com/chem
Adebayo Onigbinde is an applications
chemist based at Agilent Technologies,Wilmington, Delaware, USA.
For More Information
For more information on our productsand services, visit our Web site atwww.agilent.com/chem.
Experimental Conditions
Instrument: Agilent 1100 Series HPLC; Temp: ambient; Column: Zorbax SB-Aq,4.6 150 mm, 5 m (part number 883975-914); Mobile phase: 100% 10 mM
ammonium acetate, pH 5.4; Flow rate: 1 mL/min; Injection volume: 5 L; Diodearray detector: 254 nm; Reference: 400 nm; Bandwidth: 100 nm
DAD1 C, Sig = 254,4 Ref = 400,100 (51402B\001-0201.D)
Excipent
Z-Ceftibuten
E-Ceftibuten
min0 2 4 6 8 10 12 14
mAU
0
20
40
60
100
80
6.3
45
8.1
10
13.4
77
N
NH
N
S
S
O
O
O
O
H2NHO
OH
HH
H
N
NH
N
S
S
O
O
OH2N
HO
HO
HHHO
250.00
200.00
150.00
100.00
50.00
0.00
0 5 10 15 20
Concentration (g/mL)
Averagearea
y = 13.86x - 0.6392
R2 = 0.9955
Ceftibuten
Figure 2 Separation of ceftibuten isomers with 100% aqueous phases on Zorbax
SB-Aq column. Concentration of ceftibuten dihydrate: 3.0 mg/mL.
Figure 3. Good linearity and a low limit of detection for ceftibuten using a Zorbax
SB-Ag column.