1. Peter Kovarik and Yves LeBlanc
A Combined Electrospray and APCI ionization system
Peter Kovarik and Yves LeBlanc
system offers simultaneous operation of Electrospray and
APCI or software controlled selection of the ionization
process allowing a rapid transition between the two
techniques

2. Dual Source “Duo”
Turbo “V” Source

3. Applications of Dual Source
quantitative applications:
1. method development (choosing the best ionization mode)
2. multiple ionization modes in a single run for multiple
components.
B. qualitative applications:
1. alternate full scan APCI/ESI for spectra interpretation

4. Two period experiment: 0-2.1 minutes TIS, 2.2-4.0 minutes APCI
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0.0
4.0e4
Intensity, cps
Time, min
Mometasone
Minoxidil
APCI
3.6e4
TIS
4.4e4
Two period experiment: minutes TIS, minutes APCI

5. 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 Time, min Relative Intensity
Ion suppression – comparison of TIS and APCI
post column split infusion introduced
a steady flow of Minoxidil into the source,
blank urine sample was then injected onto the column
and variation in the MRM signal was monitored
APCI shows a lower susceptibility to matrix suppression
red trace is APCI
blue trace is TIS
100%

6. Complementary information offered by the APCI/ESI response
240
250
260
270
280
290
300
310
320
330
m/z, amu
0.0
100%
Relative Intensity
297.0
313.1
245.1
287.1
255.2
321.1
265.1
329.1
240.2
2e5cps
1e6cps
red trace is APCI
blue trace is TIS
200
600
220.2
242.2
371.2
264.0
329.2
369.2
505.4
Ritalinic acid, M+H
Salicyl acyl
Glucuronide
M-H
Complementary information offered by the APCI/ESI response
no M-H
M+H
M+Na

7. Performance comparison with a Turbo V source
Sensitivity:
Reserpine by ESI based TurboIonSpray ( at 0.2mL/min)
normalized peak height is ~0.8 of the dedicated source
normalized S/N is ~0.5 of the dedicated source
Reserpine by APCI ( at 1mL/min)
normalized peak height is ~0.6 of the dedicated source
normalized S/N is ~0.6 of the dedicated source
Background: similar performance to a dedicated source
Stability: similar performance to a dedicated source

8. Examples:
A. Gemcitabine and its metabolite highlights the search for maximum sensitivity with ionization switching in a single LC run
B. Detection of Salicyl Acyl Glucuronide is an example of a qualitative application that uses fast switching for confirmation of compound structure

9. MRM analysis of Gemcitabine and it’s metabolite
two period experiment sets an optimum ionization, ion polarity
and desolvation temperature for each compound
compounds and LC conditions were provided by Dr. Fabio Garofolo (LLBR – Eli Lilly Canada Inc.)
1.0
2.0
3.0
4.0
5.0
Time, min
Relative Intensity
APCI
positive
ion mode
T=450C
TIS
negative
T=550C
metabolite
switch
Parent drug
further results presented
as poster #308 (Wed)
100%

10. Identification of salicylic acid glucuronide metabolites
neutral loss experiment (loss of 176amu)
COOH OH
salicylic acid MW 138 Da
100% 1 2 3 4 5 6 7 8 9 10
Time, min
Relative Intensity
100
200
300
m/z, amu
313
269
174.7
137
113
295
100
200
300
m/z, amu
313
285
174.8
137
113
salicyl acyl glucuronide MW 314 Da
salicyl glucuronide MW 314 Da
Blue trace – TIS
Red trace - APCI

11. TIC - neutral loss of 176 amu Blue trace – TIS Red trace - APCI
Intensity 1 2 3 4 5 6 7 8 9 10
Time, min
TIC - neutral loss of 176 amu
Blue trace – TIS
Red trace - APCI
Extracted mass 313 amu
salicyl glucuronide MW 314 Da
salicyl acyl glucuronide MW 314 Da
red trace – APCI Q1 scan – extracted mass 137 amu
blue trace – TIS Q1 scan – extracted mass 313 amu
COOH OH
salicylic acid MW 138 Da
Confirmation of thermally decomposing glucuronide

12. Summary:
-Combined ionization source offers an expanded
compound class coverage over single mode sources
-Duo source allows fast empirical determination and
selection of best ionization for compound detection
-Qualitative applications offer an advantage in spectra
interpretation through identification of adducts and
through structural confirmation of thermally labile
compounds
Acknowledgments:
Takeo Sakuma, Stan Potyrala and Toha Dang