(originally aired 03-29-12) Initially U.S. EPA 300.1 (Ion Chromatography with conductivity detection) sufficed for bromate regulatory requirements. As bromate toxicity concerns increased, lower regulatory limits (and lower MDLs) were imposed, leading to use of EPA 317’s and 326’s postcolumn derivatization and visible detection methods, although they sacrifice robustness and ease of use. Simultaneously, enhancements in column chemistry improved the MDLs possible with EPA 300.1. And since it is still impossible to overcome matrix effects with certain drinking water samples, EPA 302’s 2-D IC method was approved to maintain testing ease-of-use and robustness. Here, experts detail the bromate analysis methods and necessary validation steps.

1. Comparison of EPA Methods
300.1, 317, 326 and 302 for
Bromate Analysis Part 1
Richard F. Jack, PhD
Manager, Global Market Development
March 29, 2012

2. Bromate Regulations and Method Comparisons
• Disinfection byproducts
• Toxicology
• Bromate method summary
• EPA Method 300.1
• EPA Methods 300.1 and 317
• EPA Methods 300.1 and 326
• Conductivity detection for bromate analysis
• Method comparison using Thermo Scientific Dionex IonPac AS23 and
AS19 columns
• Method comparisons using Dionex IonPac™ AS9-HC and AS19 columns
• Matrix interference and analysis of bromate
• Two-dimensional ion chromatography (2D-IC)

3. Drinking Water Disinfection: Treatment and Byproducts
 Disinfection byproducts are formed when
disinfectants used in water treatment plants react
with bromide and/or natural organic matter.
Disinfection
Treatment
Disinfection
Byproducts
Chlorination
Trihalomethanes
Haloacetic Acids
Chlorate
Chlorine Dioxide
Chlorite
Chlorate
Chloramine
Chlorate
Ozonation
Bromate

4. Toxicology of Bromate
• Clinical signs of bromate poisoning in humans include:
• Anemia, hemolysis, renal failure, hearing loss.*
• Carcinogenicity:
• Animals: International Agency for Research on Cancer (IARC)
has concluded that bromate is carcinogenic in animals.
• Humans: IARC has assigned bromate to Group 2B
(possibly carcinogenic to humans).
* World Health Organization (WHO), Geneva, Switzerland, 2000

5. EPA Bromate Method Summary
EPA
Methods
Column(s)
300.0 (B)
Dionex Ion Pac
AS9-HC
AS23
AS19
Carbonate
Carbonate
Hydroxide
IC-Suppressed
Conductivity
300.1
Dionex IonPac
AS9-HC
AS23
AS19
Carbonate
Carbonate
Hydroxide
2D-IC Suppressed
Conductivity
302.0a
Dionex IonPac
AS19, 4 mm
AS24, 2 mm
Hydroxide
317.0
Dionex IonPac
AS9-HC
AS19
Carbonate
Hydroxide
IC Suppressed
Conductivity with
Postcolumn Acidified KI
326.1
Dionex IonPac
AS9-HC
AS19
Carbonate
Hydroxide
IC-ICP-MS
321.8
Dionex CarboPac
PA100
Technique
IC Suppressed
Conductivity
IC Suppressed
Conductivity with
Postcolumn ODA
Eluent
MDL (ppb)
Conductivity
5.0 0
1.63
0.32
5.0 0
1.63
0.32
0.036
Conductivity
UV
0.32
0.14
0.29
0.17
0.01

6. Bromate Method, Application Note and Matrix
Recommendations
EPA
Method
Application
Note
IC Suppressed
Conductivity
300.0 (B)
167, 184
Low salt conditions
IC Suppressed
Conductivity
300.1
167, 184
Low salt conditions
IC Suppressed
Conductivity with
Postcolumn ODA
317.0
168
Tolerates higher salt conditions
IC Suppressed
Conductivity with
Postcolumn Acidified KI
326.1
171
Tolerates higher salt conditions
2D-IC Suppressed
Conductivity
302.0
187
Tolerates higher salt conditions
IC-ICP-MS
321.8
Technique
Matrix
Tolerates higher salt conditions

7. Bromate Method, Application Note and Matrix
Recommendations (cont’d)
Application
Note
Technique
Method
IC Chemically
Suppressed Conductivity
ISO 15061,
ASTM 6581
167, 184
IC Suppressed
Conductivity with
Postcolumn Acidified KI
ISO Pending
171
IC Suppressed
Conductivity with
Postcolumn Acidified KBr
Japan
Matrix
Drinking water only,
ground- and wastewater
only if low salt conditions
Tolerates higher salt
conditions.
Tolerates higher salt
conditions.

8. Bromate Regulations and Methods Timeline
1993:
WHO MCL 25 ppb
1993: EPA 300.0
2003:
WHO MCL 10 ppb
1998:
U.S. EPA MCL of 10 ppb
EU MCL 50 to 10 ppb
1997: EPA 300.1
2004:
U.S. stage II DBP Rule MCLG “0”
U.S. FDA regulates in BW
2000: EPA 317
2009: EPA 302
2002: EPA 326
1995: AN 101
Carbonate
2003: AN 149
Carbonate,
Postcolumn I3
2004: AN 136
Carbonate,
Postcolumn ODA,
AN 167 Hydroxide,
Dionex IonPac AS19
2009: AN 208
Carbonate, CRD
Dionex IonPac AS23
2006: AN 168
Hydroxide
Postcolumn ODA
2009: AN 171
Hydroxide,
Postcolumn I3
New Dionex
IonPac AS19
2007: AN 184
Hydroxide, Carbonate
Eluent Comparison
2007: AN 187
Hydroxide, 2D- IC

9. EPA 300.1 Comparison of Dionex IonPac AS9-SC and
AS9-HC Columns for Oxyhalide Determination
1
14
Columns:
6 8
7
3
2
µS
A
9
Flow Rate: 1 mL/min
Inj. Volume: 25 µL
Detection: Suppressed Conductivity, Thermo
Scientific Dionex ASRS Anion SelfRegenerating Suppressor,Thermo
Scientific Dionex AutoSuppression
device, external water mode
10
B
4
µS
2
3
8
6
5
7
10
Peaks:
9
0
0
5
A. 1.8 mM Sodium carbonate
1.7 mM Sodium bicarbonate
B. 9.0 mM Sodium carbonate
10
0
1
A. Dionex IonPac AG9-SC, AS9-SC
B. Dionex IonPac AG9-HC, AS9-HC
Eluent:
45
10
15
Minutes
20
25
1. Fluoride
2. Chlorite
3. Bromate
4. Chloride
5. Nitrite
6. Bromide
7. Chlorate
8. Nitrate
9. o-Phosphate
10. Sulfate
3.0 mg/L
10.0
20.0
6.0
15.0
25.0
25.0
25.0
40.0
30.0

10. Effect of Matrix Concentration on
Bromate Peak Shape and Recovery
Column:
Dionex IonPac AG9-HC,
AS9-HC, 4 mm
Flow Rate:
1.0 mL/min
Concentration: 9.0 mM Carbonate
Suppressor:
Thermo Scientific Dionex
AAES Anion Atlas Electrolytic
Suppressor
Current:
58mA
Loop:
500 µL (large loop)
Oven:
30 °C
E
1
D
1
C
µS
Peak 1:
1
Bromate 0.005 mg/L
B
Matrix
Concentration: E
D
C
B
A
1
A
1
0
4
Minutes
8
12
200 ppm of CI and SO4
150
100
50
0

11. System Configuration
EPA Methods 300.1 and 317 for Bromate
Pump
Guard
PCR
Reservoir
ODA
Separation
Mixing
Tee
Absorbance
Detector
Suppressor
Conductivity
Detector

12. EPA Methods 300.1 and 317 for Trace Bromate
Flow Rate:
µS
1
2
0
0
5
(B)
12
AU
45
10
15
20
Method
317.0
1.3 mL/min
225 mL
Detection:
Method
300.1
9.0 mM Sodium carbonate
Inj. Volume:
(A)
Dionex IonPac AG9-HC, AS9-HC
(4 × 250 mm)
Eluent:
3
0.25
0.015
Column:
A) Suppressed conductivity
Dionex ASRS™ ULTRA,
Dionex AutoSuppression™
external water mode
B) Absorbance, 450 nm
Postcolumn
Reagent:
PCR Flow Rate: 0.7 mL/min
Postcolumn
Heater:
Peaks:
0
0
5
10
Minutes
o-dianisidine
15
20
60 °C
1. Chlorite
2. Bromate
3. Surrogate (DCAA)
4. Bromide
5. Chlorate
20 mg/L (ppb)
5
1000
20
20
Chromatograms courtesy of Herb Wagner, U.S. EPA.

13. System Configuration for EPA Method 300.1 and 326.0
for Trace Bromate
Pump
PC10 PCR
Reservoir
KI
Guard
Suppressor
Separation
Thermo Scientific
Dionex AMMS
MicroMembrane
Suppressor
KI→HI
Mixing
Tee
BrO3– + HI → I3
Color (352) nm)
Conductivity
Detector
Knitted RX Coil
PCH-2 Heater
Absorbance
Detector
Waste

14. Details of Postcolumn Reagent Generation with
Dionex AMMS™ III
CationExchange
Membrane
Waste
CationExchange
Membrane
From PC10
Waste
KI
K+ HSO4–
K+ HSO4–
K+
K+
I
I
–
–
H+
H+
H+ + I–
H+ HSO4–
H+ HSO4–
300 mM Sulfuric Acid
300 mM Sulfuric Acid
To Mixing Tee

15. Bromate Oxidizes Iodide to Triiodide in
EPA Method 326 through Postcolumn Reaction
Mixing Tee
KI + H+ from
Dionex AMMS
BrO3– + 3I– + 3H+
3HOI + 3I– + 3H+
3I2– + 3I–
Bromate
from Column
3HOI + Br–
3I2 + 3H2O
3I3–
I3–
Detect I3– at 352 nm

16. Analysis of Bromate and Common Anions
in Bottled Water
27.10
3
(A)
µS
Column:
Eluent:
Temp:
Flow Rate:
Inj. Volume:
Detection:
Method
300.1
5
2
4
26.10
0
0.004
5
10
15
(B)
Method
326.0
AU
Postcolumn
Reagent:
Acidified KI
20 PCR Flow Rate: 0.4 mL/min
Postcolumn
Heater:
80 °C
Peaks:
2
Dionex IonPac AG9-HC, AS9-HC, 4 mm
9.0 mM Sodium carbonate
30 °C
1.3 mL/min
225 µL
A) Suppressed conductivity, Dionex
AAES Anion Atlas™ Electrolytic
Suppressor, external water mode
B) Absorbance, 352 nm
A)
1.
2.
3.
4.
5.
Conductivity
Chlorite
not detected
Bromate
1.52 µg/L (ppb)
DCA*
Bromide
1.12
Chlorate
1.08
B) Postcolumn Reagent/UV
2. Bromate
1.84 µg/L (ppb)
–0.001
0
5
10
Minutes
15
20 * DCA = Dichloroacetate quality control surrogate

17. Evalution of EPA Methods 300.1, 317, and 326
• EPA Method 300.1 (B/C) with conductivity detection
• High LOD
• Chloride removal required with some samples leading to added costs and time
• EPA Method 317 postcolumn addition of ODA followed by visible
detection
•
•
•
•
Requires extra hardware
Requires frequent optimization of PCR reagent flow rate
Reagent purity was an issue
Handling of ODA a human carcinogen
• EPA Method 326 postcolumn addition of hydroiodic acid that combines
with bromate to form the triiodide anion followed by UV-vis detection
• Requires hardware
• Requires in situ generation of hydroiodic acid by the acidification of potassium
iodide
• Potassium iodide is photo-sensitive
• Requires frequent optimization of PCR reagent flow rate

18. Improving EPA Method 300.1 Conductivity Detection
for Bromate
• Hydroxide eluent suppression produces water, providing the lowest
possible background conductivity
•
•
•
•
Lower noise
Improved detection limits
Larger linear working range
Eluent is conveniently generated on line
• New columns with increased capacity bind matrix anions like Cl.
Year
Column
Capacity
Eluent
1993
Dionex IonPac AS9SC
30
carbonate
1993
Dionex IonPac AS9HC
190
carbonate
2007
Dionex IonPac AS23
320
carbonate
2007
Dionex IonPac AS19
240
hydroxide

19. Chromatogram of Mineral Water A Spiked with 1 µg/L Each
Chlorite and Chlorate and 0.5 µg/L Bromate
Column:
Eluent:
Dionex IonPac AG19, AS19 4 mm
10 mM KOH 0–10 min, 10–45 mM
10–25 min, 45 mM 25–30 min
Eluent Source: Thermo Scientific Dionex EGC II
KOH with CR-ATC
Temperature: 30 °C
Flow Rate:
1.0 mL/min
Inj. Volume:
250 µL
Detection:
Suppressed conductivity, Dionex
ASRS ULTRA II, recycle mode
1
2
0.5
1
4
8
9
3
10
11
Peaks:
µS
0.2
0
5
10
15
Minutes
20
25
30
1. Fluoride
2. Chlorite
1.0 µg/L
3. Bromate
0.5
4. Chloride
5. Nitrite
6. Chlorate
1.0
7. Bromide
8. Nitrate
9. Carbonate
10. Sulfate
11. Phosphate

20. Hydroxide vs Carbonate Eluents for Separation of
Common Anions and DPBs in Mineral Water
Column:
0.5
A
1
8
4
9
10
A) Dionex IonPac AS19
B) Dionex IonPac AS23
Eluent:
A. Hydroxide
B. Carbonate/bicarbonate
Detection: Suppressed conductivity
11
7
µS
Peaks
6
2
1. Fluoride
2. Chlorite
8.8
3. Bromate
4.7
4. Chloride
5. Nitrite
6. Chlorate
13.5
7. Bromide
8. Nitrate
9. Carbonate
10. Sulfate
11. Orthophosphate
5
3
0.2
0.7
B
1
4
8
10
11
9
µS
A
B
11.3 µg/L
5.1
9.5
3
2
5 6 7
-0.1
0
5
10
15
Minutes
20
25
30
• Both eluents show excellent anion and
oxyhalide separation.
• Trace oxyhalides chlorite, bromate, and
chlorate are well resolved.
• Hydroxide does not show the water dip.
• Elution order of orthophosphate and sulfate are
reversed.

21. Reagent-Free™ IC (RFIC™) System Using Hydroxide
Is Sensitive—Hydroxide vs Carbonate Eluents
Analyte
Range
(µg/L)
Linearity
(r2)
Retention
Time
Precision
(% RSDb,c)
Peak Area
Precision
(% RSD)
MDL
Standard
(µg/L)
MDL
Calculated
(µg/L)
Dionex IonPac AS19 Column—Hydroxide Eluent
Chlorite
2-50
0.9999
0.04
1.20
1.0
0.18
Bromate
1-25
0.9995
0.03
1.40
2.0
0.31
Chlorate
2-50
0.9999
0.01
0.54
1.0
0.28
Dionex IonPac AS23 Column—Carbonate/Bicarbonate Eluent
Chlorite
10-50
0.9999
0.07
2.20
5.0
1.02
Bromate
5-25
0.9998
0.07
2.63
5.0
1.63
Chlorate
10-50
0.9998
0.11
2.48
9.0
2.05
a
b
c
See Application Note 184 for conditions
RSD = relative standard deviation, n = 7
Quality control standard contained 10 ppb each of chlorite, chlorate, and bromide and 5 ppb bromate

22. Resolution and Sensitivity Improvement with Hydroxide
Eluent + Gradient Separation
Chloride (Dionex IonPac AS18 column, hydroxide)
3.0
1 min
µS
0
–0.5
2.0
1 min
µS
0
–0.5
Area: 0.2743 µS•min
Height: 2.98 µS
Plates: 22,843 EP
Chloride (Dionex IonPac
AS14 column, carbonate)
Area: 0.1767 µS•min
Height: 1.35 µS
Plates: 5,172 EP
Sulfate (Dionex IonPac AS18 column, hydroxide)
Area: 0.185 µS•min
Height: 1.97 µS
Plates: 42,068 EP
Sulfate (Dionex IonPac
AS14 column, carbonate)
Area: 0.1301 µS•min
Height: 0.35 µS
Plates: 4,644 EP

23. Affect of Cl Concentration on Bromate Recovery Using
a Dionex IonPac AS19 Column
100
80
60
% RSD
Bromate Recovery
40
20
0
0
50
100
150
Cl conc (ppm)
200
250

24. Comparison of EPA Methods
300.1, 317, 326 and 302 for
Bromate Analysis
Part 2: Quality Assurance Requirements
for EPA Method Development
Herbert P. Wagner, Analytical Chemist
March 29, 2012
1

25. Outline
• Challenge to analyze trace levels of an
analyte in large excess of interfering
components
• Surface and ground waters vary across the
United States
• Synthetic matrices and other quality
assurance protocols incorporated by U.S.
EPA Office of Ground Water and Drinking
Water (OGWDW) to ensure method precision,
accuracy and robustness
2

26. Quality Assurance Requirements for
EPA Method Development
• High-ionic-strength matrices may overload
exchange sites on the column and cause
dramatic shifts in retention time.
• Suppressed ion chromatographic (IC)
methods for inorganic anions were first used
by U.S. EPA Office of Research and
Development in late 1980’s.
• Information Collection Rule (ICR) for bromate
occurrence data in U.S. was scheduled from
July 1997 to early 1999.
3

27. Quality Assurance Requirements for
EPA Method Development
• Selective Anion Concentration (SAC) Method
was developed by U.S. EPA Office of Water
in 1995-96.
• Very complex research method used to
support bromate data collection during ICR
• Never published as an EPA monitoring
method
• Bromate occurrence data collected during
ICR showed need for more user-friendly
method required for bromate.
4

28. Quality Assurance Requirements for
EPA Method Development
• Pretreatment cartridges used to remove
anionic interferences in SAC method
• Introduction of Thermo Scientific Dionex
IonPac AS-9 HC column afforded fourfold
increase in injection volume, and therefore
increased detection limit (DL) for bromate
• Increased injection volume created larger
interferences which could overshadow gains
in sensitivity
5

29. Quality Assurance Requirements for
EPA Method Development
• EPA Method 300.1 introduced in 1997
provided a more user-friendly, sensitive
method for analysis of bromate in drinking
water.
• Synthetic high ionic water (HIW) was first
introduced as QC sample to ensure DL not
affected by ionic strength matrix.
• HIW was a reagent water containing 100mg/L
each of carbonate, chloride and sulfate and
10mg/L nitrate (as N) and phosphate (as P).
6

30. Quality Assurance Requirements for
EPA Method Development
• Lowest Concentration Minimum Reporting
Level (LCMRL) was introduced by EPA
OGWDW in 2004.
• Difficult to find consistently uniform
fulvic/humic acid
• HOW replaced with municipal surface water
with a year-round total organic carbon (TOC)
of 4–5 mg/L.
8

31. Quality Assurance Requirements for
EPA Method Development
• The complexity of two-dimensional IC required the
very stringent QA protocols developed by EPA
OGWDW for the analysis bromate and perchlorate be
implemented into EPA Methods 302.0 and 314.2.
• A printout of the first dimension high level Continuing
Calibration Check (CCC) and Laboratory Fortified
Synthetic Sample Matrix (LFSSM) CCC
chromatograms was the final QA requirement
implemented.
• These requirements ensure that the target analyte
falls within the “cut window” in reagent water (RW)
and very high ionic Laboratory Synthetic Sample
Matrix (LSSM).
9

32. Quality Assurance/Control
Definitions
• Analysis Batch: A sequence of field samples, which
are analyzed within a 24-hour period and include no more
than 20 field samples. An Analysis Batch must also
include all required QC samples which do not contribute
to the maximum field sample total of 20.
• Laboratory Reagent Blank (LRB): An aliquot of
reagent water or other blank matrix that is treated exactly
as a sample, including exposure to storage containers.
The LRB is used to determine if the method analyte or
other interferences are present in the laboratory
environment, reagents, or apparatus.
10

33. Quality Assurance/Control
Definitions (Cont’d)
• Calibration Standard (CAL STD): A solution of
the target analyte prepared from a Primary Dilution
Solution. The CAL solutions are used to calibrate the
instrument response with respect to analyte
concentration.
• Continuing Calibration Check Standard
(CCC): A calibration check standard containing the
method analyte, which is analyzed periodically
throughout an Analysis Batch to verify the accuracy of
the existing calibration for that analyte.
11

34. Quality Assurance/Control
Definitions (Cont’d)
• Laboratory Fortified Blank (LFB): An aliquot of
reagent water or other blank matrix to which a known
quantity of the method analyte is added. The LFB is
analyzed exactly like a sample. Its purpose is to
determine whether the methodology is in control, and
whether the laboratory is capable of making accurate and
precise measurements.
• Laboratory Duplicate (LD): Two sample aliquots
(LD1 and LD2) from a single field sample bottle analyzed
separately with identical procedures. Analyses of LD1
and LD2 indicate precision associated specifically with
laboratory procedures by removing variation contributed
from sample collection and storage procedures.
12

35. Quality Assurance/Control
Definitions (Cont’d)
• Laboratory Fortified Sample Matrix (LFSM):
An aliquot of a field sample to which a known quantity of the
method analyte is added. The LFSM is processed and analyzed
exactly like a field sample, and its purpose is to determine
whether the field sample matrix contributes bias to the
analytical results. The background concentration of the analyte
in the field sample matrix must be determined in a separate
aliquot and the measured value in the LFSM corrected for the
native concentration.
• Laboratory Fortified Sample Matrix Duplicate
(LFSMD): A second aliquot of the field sample used to
prepare the LFSMD, which is fortified and analyzed identically to
the LFSM. The LFSMD is used instead of the Laboratory
Duplicate to assess method precision and accuracy when the
occurrence of the target analyte is infrequent.
13

36. Quality Assurance/Control
Definitions (Cont’d)
• Laboratory Synthetic Sample Matrix (LSSM):
An aliquot of reagent water that is fortified with the
sodium salts of chloride, bicarbonate, sulfate and, if
required, phosphate and nitrate. The purpose of the
LSSM is to ensure method precision and accuracy in a
simulated very-high-ionic-strength drinking water matrix.
• Laboratory Fortified Synthetic Sample Matrix
(LFSSM): An aliquot of the LSSM which is fortified with
the target. The LFSSM is used to set the start time for the
cut window in the first dimension and also used to
ensure the precision and accuracy for the method is in
control. The LFSSM samples are treated like the CCCs.
14

37. Quality Assurance/Control
Definitions (Cont’d)
• Laboratory Fortified Synthetic Sample Matrix
Continuing Calibration Check Standard
(LFSSM CCC): An aliquot of the LSSM which is
fortified with the target analyte at a concentration equal
to one of the CCCs. A LFSSM CCC at a concentration
equal to the highest calibration level should be analyzed
near the beginning or at the end of each Analysis Batch
to confirm that the first dimension heart-cutting
procedure has acceptable recovery in high inorganic
matrices.
15

38. Quality Assurance/Control
Definitions (Cont’d)
• Lowest Concentration Minimum Reporting
Level (LCMRL): The single-laboratory LCMRL is the
lowest true concentration for which the future
recovery is predicted to fall between 50–150%
recovery with 99% confidence.
• Minimum Reporting Level (MRL): The minimum
concentration that can be reported by a laboratory as a
quantified value for the target analyte in a sample
following analysis. This defined concentration must be
no lower than the concentration of the lowest calibration
standard for the target.
16

39. Analysis Batch Sequence
Injection #
Sample Description
Acceptance Criteria
1
LRB
≤ 1/3 MRL
2
CCC at the MRL
Recovery of 50–150%
3
LFB
≤ MRL 50–150% of Value
> MRL 80–120% of Value
4
Sample 1
Normal Analysis
5
Sample 2
Normal Analysis
6
Sample 2 LFSM
Recovery of 80–120%
7
Sample 2 LFSMD
% RPD = ± 20%
8
Sample 3
Normal Analysis
9
Sample 4
Normal Analysis
10
Sample 5
Normal Analysis
11
Sample 6
Normal Analysis
12
Sample 7
Normal Analysis
17

40. Analysis Batch Sequence (Cont’d)
Injection #
Sample Description
Acceptance Criteria
13
Sample 8
Normal Analysis
14
Sample 9
Normal Analysis
15
Sample 10
Normal Analysis
16
CCC at Mid Level
Recovery of 80–120%
17
Sample 11
Normal Analysis
18
Sample 12
Normal Analysis
19
Sample 13
Normal Analysis
20
Sample 14
Normal Analysis
21
Sample 15
Normal Analysis
22
Sample 16
Normal Analysis
23
Sample 17
Normal Analysis
24
Sample 18
Normal Analysis
18

41. Analysis Batch Sequence (Cont’d)
Injection #
Sample Description
Acceptance Criteria
25
Sample 19
Normal Analysis
26
Sample 20
Normal Analysis
27
CCC at High Level *
Recovery of 80–120%
28
LFSSM CCC at High Level *
Recovery of 80–120%
* Printout of first-dimension chromatogram required
19

42. EPA Method 302.0 Two-Dimensional
Matrix Elimination IC
• Introduced for the trace analysis in the presence
of large amount of matrix ions
• Uses a high capacity 4 mm column in the first
dimension to separate the analytes from the
matrix ions
• After separation, the suppressed effluent portion
containing the analytes is concentrated onto a
concentrator column and subsequently analyzed
in the second dimension using a smaller format
column with a different selectivity
20

43. EPA Method 302.0 Two-Dimensional
Matrix Elimination IC (cont.)
– resulting in enhanced sensitivity and selectivity
– introduction of capillary scale ion
chromatography provides a unique opportunity to
further improve the detection limits by using the
capillary scale ion chromatography in the second
dimension
– outline 2-D methods used for the analysis of
anions in drinking water
– 2-D method for bromate in drinking water
21

44. Current Approaches in IC
Trace Analysis
• Samples with Low Levels of Matrix Ion
•
– Analysis is typically performed using preconcentration or large-volume direct injections
– Example applications: Analysis of ultrapure water
(UPW)
Samples with High Levels of Matrix Ions
– Pre-concentration or large-volume direct injection
may not be possible because the matrix ions may
co-elute with species of interest or may elute
species of interest leading to recovery and
integration issues due to band broadening
– Example applications: Analysis of drinking water,
wastewater
22

45. Current Approaches in IC
Trace Analysis (cont’d)
• Samples with High Levels of Matrix Ions
– Requires a sample pretreatment step using solidphase extraction (SPE) cartridges
• Example: A silver form cation-exchange resin
used to remove high levels of chloride
• Multiple cartridges may be needed
• SPE methods
– Off-line method
– Labor intensive
– adds costs from cartridges and equipment
23

46. Matrix Elimination Ion
Chromatography (MEIC) Features
Large-Loop
• Allowscolumn) Injection in the First Dimension
(4 mm
– Possible to inject a larger loop volume than the
standard approach because the capacity and
selectivity of the analytical column in the first
dimension dictates the recovery, and the analyte
of interest is analyzed in the second dimension
• Focuses Ions of Interest in a Concentrator Column
After Suppression in the First Dimension
– Hydroxide eluent converted to DI water, providing
an ideal environment for focusing or
concentrating the ions of interest
sdPittcon 2012
24

47. Matrix Elimination IC Features (cont’d)
Analysis in
• Provides Chemistry the Second Dimension Using a
Different
– Enhanced sensitivity
– For example, the cross-sectional area of a 1 mm
column is one sixteenth the area of a
4 mm column, providing a sensitivity enhancement
factor of ~16
Analysis in
• Provides Chemistry the Second Dimension Using a
Different
– Enhanced selectivity
• Easily Implemented on the ICS-3000/ICS-5000 System
25

48. Matrix Elimination Ion Chromatography (MEIC) —
Instrumental Setup
1st Dimension
Pump
waste
2nd Dimension
Autosampler1
EG
Injection Valve 1
Large Loop
CRD 2
External Water
Load
Inject
Diverter Valve
Suppressor 2
waste
Injection Valve 2
waste
1st Dimension
Column (4 mm)
CD 2
waste
CD 1
External Water
2nd Dimension Column (2 mm)
waste
Suppressor 1
CRD 1
Concentrator Pump
Column
(UTAC-ULP1)
Transfer to 2D
Load Concentrator
EG
waste
26

49. Effect of Matrix Concentration on
Bromate Peak Shape and Recovery
.
IonPac® AG9-HC, AS9-HC,
4 mm
Flow Rate:
1.0 mL/min
Concentration: 9.0 mM Carbonate
Suppressor: AAES
Current:
58 mA
Loop:
500 µL
Oven:
30 °C
Column:
E
1
D
1
C
1
B
Peaks:
A
Matrix
Concentration:
and SO4
1
1
4
Minutes
8
12
Bromate 0.005 mg/L
A) 0
B) 50
C) 100
D)150
E) 200
ppm CI
ppm CI and SO4
ppm CI and SO4
ppm CI and SO4
ppm CI and SO4
25633
27

50. 2-D METHODS FOR DRINKING
WATER
• Using 4mm columns in the first dimension and 2 mm
columns in the second dimension
−EPA Method 302.0 for the analysis of bromate
−EPA Method 314.2 for the analysis of perchlorate
• Using 4mm columns in the first dimension and
capillary columns in the second dimension in
developmental stage
−analysis of bromate
−analysis of chromate
−analysis of HAA5
28

51. Sensitivity
Flow Rate
(mL/min)
Sensitivity
1
1
Second (2 mm)
0.25
4
Second (0.4 mm)
0.01
100
Dimension
First (4 mm)
29

52. Determination of Trace Bromate in a Bottled
Water Sample Using a 2-D Capillary RFIC
System
A. First-Dimension Conditions
Column:
IonPac® AG19, AS19, 4 mm
Flow Rate:
1.0 mL/min
Eluent:
10 to 60 mM KOH (EGC-KOH )
Suppressor: 4-mm SRS 300
Inj. Volume: 1000 µL
Temperature: 30 °C
Bromate
0.5
µS
-0.3 1
17.0
——
——
——
——
B. Second-Dimension Conditions
Column:
AS20 (0.4 mm x 25 cm)
Flow Rate:
10 µL/min
Eluent:
35 mM KOH (EGC-KOH)
Suppressor: Capillary Anion Suppressor
Temperature: 30 °C
Concentrator: Capillary concentrator,
2500 µL of 1st dimension
suppressed effluent (7.5 to 10 minutes)
Dionized water
Brand A bottled water (54 ng/L)
100 ng/L bromate in deionized water
30 ng/L bromate in deionized water
Minutes
20.0
30

53. Conclusions
• 2-D IC has met or exceeded all EPA requirements for
robustness, precision and accuracy.
• Published since 2005 as a compliance monitoring
method.
• 2-D IC has also been demonstrated for perchlorate
EPA 314.2
• Capillary IC format in the second dimension is
allowing ppt level detection for bromate.
• A 2-D IC method for HAA5 is currently undergoing
secondary lab validation studies.
31

54. Comparison of EPA Methods
300.1, 317, 326 and 302 for
Bromate Analysis Part 3
Richard F. Jack, PhD
Manager, Global Market Development
March 29, 2012

55. EPA Method 302 2D-IC for Bromate Analysis
First Dimension—Dionex IonPac AS19 Column
0.60
• EPA Method 300.1 can have low
recoveries for high Cl samples
• EPA Mehtod 317 uses a toxic, unstable
reagent
• EPA Method 326 is complicated, less
robust
µS
• 2D-IC developed for
0.30
• Direct injection method
Concentrator
Second Dimension—Dionex IonPac AS24 Column
0.64
• Easy to use
• Sensitivity
• Matrix elimination
BrO3
µS
• EPA approved methods
• EPA Method 302.0 bromate
0.54
0
10
20
Minutes
30
35
• EPA Method 314.2 perchlorate
• EPA haloacetic acids (pending)

56. New 2D Method Features
• Allows for large loop injection in the first dimension (4 mm column)
• Injection to a larger loop than the standard approach is possible since the
capacity and selectivity of the analytical column in the first dimension
dictates the recovery and the analyte of interest is analyzed in the second
dimension.
• Focus the ions of interest in a concentrator column after suppression in
the first dimension.
• Hydroxide eluent is suppressed to DI water, providing an ideal environment
for focusing or concentrating the ions of interest.
• Pursue analysis in the second dimension using a smaller column
format operated at a lower flow rate, leading to sensitivity enhancement
that is proportional to the flow rate ratio.
• For a 4 mm column operated in the first dimension at 1 mL/min and a
1 mm column operated in the second dimension at 0.05 mL/min the
enhancement factor is 20.
• Easy implementation on the ICS-5000 system

57. Schematic of a 2D-IC Configuration
First Dimension
Pump
waste
Second Dimension
Autosampler 1
EG
waste
CD 2
Injection Valve 1
CRD 2
Large Loop
External Water
Load
Inject
Suppressor 2
Injection Valve 2
waste
4 mm
Column 1
CD 1
2 mm Column 2
External Water
waste
Suppressor 1
CRD 1
Dionex IonPac
UTAC-ULP1
Concentrator
Column
Pump
Transfer to 2D
Load Concentrator
EG
waste

58. Sensitivity: Instrumental Configuration
for Bromate Analysis by 2D-IC
First Dimension
- Large-loop injection
- Partially resolve matrix
Intermediate Step
Large Loop
Suppressor
Pump
EG
4 mm
Column
Injection Valve
CRD
Cell 2
Second Dimension
- Resolve on smaller column
- Sensitivity enhancement
- Different selectivity
optional
Suppressor
0.4 mm
Column
- Remove time segment
- Trap and concentrate
Cell 1 ions of interest
CRD
Dionex IonPac UTAC-ULP1
Concentrator Column
EG
Switching Valve
Pump

59. 2D Analysis in High-Ionic-Strength Water
First Dimension
0.60
Conditions:
Column:
Primary
Secondary
Dionex IonPac
Dionex IonPac
AS19, 4 mm
AS24, 2 mm
Flow Rate:
1.0 mL/min
0.25 mL/min
Suppressor: Dionex ASRS
Dionex ASRS
ULTRA II 4 mm
ULTRA II 2 mm
Current:
161 mA
41 mA
Loop:
1000 µL
Concentrator: UTAC-ULP1, 5 x 23 mm
Oven:
30 °C
µS
0.30
0
Concentrator
Second Dimension
0.64
BrO3
µS
Peak:
Matrix:
0.54
0
10
20
Minutes
30
35
Bromate 0.5 µg/L
DI Water, high ionic water
(EPA 300.1)

60. 1D Bromate Analysis with Dionex IonPac AS19 Column
Gradient Chemistry
A. 5 ppb BrO3 Spiked with 250 ppm Cl, SO4
0.4
µS
1
–0.0
–0.1
0
5
10
15
Dionex IonPac AG19,
AS19, 4 mm
Flow Rate: 1.0 mL/min
Suppressor: Dionex ASRS ULTRA II,
4 mm
Current:
113 mA
Loop:
500 µL
Oven:
30 °C
Column:
3
2
20
25
30
35
B. 5 ppb BrO3 in Reagent Water
0.4
2
3
Peaks:
Bromate
Chloride
Sulfate
µS
1
–0.0
–0.1
0
5
10
15
20
Minutes
25
30
35
A
B
0.005 mg/L 0.005 mg/L
250
0.030
250
0.150

61. 2D Bromate Analysis with Dionex IonPac AS19
Gradient Chemistry
0.4
A. 5 ppb BrO3 Spiked
with 250 ppm Cl, SO4
Columns:
µS
1
–0.1
0
5
10
15
20
25
30
0.4
B. 5 ppb BrO3
in Reagent Water
A. Dionex IonPac AG19, AS19,
4 mm
B. Dionex IonPac AG19, AS19,
2 mm
Flow Rate:
A. 1.0 mL/min
B. 0.25 mL/min
Suppressor: A. Dionex ASRS ULTRA II, 4 mm
B. Dionex ASRS ULTRA II, 2 mm
Current:
A. 113 mA
35
B. 29 mA
Loop:
500 µL
Concentrator: TAC-ULP1
Peaks
Bromate
Chloride
Sulfate
µS
1
–0.1
0
5
10
15
20
Minutes
25
30
35
A
0.005 mg/L
250
250
B
0.005 mg/L
0.030
0.150

62. Trace Analysis of Bromate in Bottled Water by 2D-IC
Bromate
0.5
µS
-0.3 1
17
——
——
——
——
Sample A (54 ng/L)
100 ng/L bromate in deionized water
30 ng/L bromate in deionized water
Deionized water
Minutes
A. First Dimension
Column:
Dionex IonPac AG19,
AS19, 4 mm
Flow rate:
1 mL/min
Eluent:
10–60 mmol/L KOH
Eluent Source: Dionex EGC III KOH
Suppressor:
Dionex ASRS 300 (4 mm)
Inj. volume:
1000 µL
Temperature: 30 °C
B. Second Dimension
Column:
Dionex IonPac AS20
(0.4 mm)
Flow rate:
10 µL/min
Eluent:
35 mmol/L KOH
Eluent Source: Dionex EGC-KOH
(Capillary)
Suppressor:
Thermo Scientific Dionex
ACES 300 Anion Capillary
Electrolytic Suppressor
Temperature: 30 °C
Concentrator: Capillary concentrator,
20
2500 µL of the suppressed
effluate from the first
dimension (7.5–10 min)

63. Sensitivity Improvement
• RFIC using hydroxide eluents suppressed to water, lower background
• RFIC in 2D-IC 4/2 mm results in 4x sensitivity enhancement
• 2D-IC in 4/0.4 mm format improves sensitivity 100x
Dimension
Sensitivity
Flow Rate (mL/min)
First (4 mm)
1
1
Second (2 mm)
4
0.25
100
0.01
Second (0.4 mm)

64. Sensitivity: Instrumental Configuration for 2D-IC
First Dimension
- Large loop injection
- Partially resolve
analyte from matrix
Load
Inject
Large Loop
Pump
EG
Suppressor
Column
Injection Valve 1 4 mm
Second Dimension
- Separate on
Cell 2
smaller ID column
- Different selectivity
- Signal enhancement
Intermediate Step
Cell 1
CRD
CRD
4-mm
0.4-mm
2-mm
Column
Column
Suppressor
Pump
Transfer to 2D
Load Concentrator
Concentrator
Valve 2
EG
- Separate Transfer
cut volume
- Trap and focus
ions of interest

65. Trace Perchlorate Using 2D-IC with Second Column in
Capillary Format
A. First Dimension Conditions
First Dimension
Chromatogram
0.1 µS Full Scale
0.10
µS
Column:
Flow rate:
Eluent:
Eluent Source:
Suppressor:
Inj. volume:
Temperature:
1
Dionex IonPac AG16, AS16, 4 mm
1.0 mL/min
65 mM KOH
Dionex EGC III KOH
Dionex ASRS 300
4000 µL
30 °C
B. Second Dimension Conditions
0.0
60
0
10.0
Second Dimension
Chromatogram
10 µS Full Scale
µS
Column:
Flow rate:
Eluent:
Suppressor:
Temperature:
Concentrator:
1
Peak:
Dionex IonPac AS20, 0.4 mm
10 µL/min
35 mM KOH
Dionex ACES™ 300
30 °C
Capillary concentrator,
5000 µL of first dimension
suppressed effluent (19–24 min)
1. Perchlorate
1.0 µg/L
Perchlorate Peak Area
0.0
0
Minutes
60
First Dimension:
Second Dimension:
0.0115 µS*min
1.75 µS*min
Capillary IC provides a 100-fold increase in sensitivity!

66. Trace Analysis of Perchlorate with 2D-IC
2.5
A. First Dimension Conditions
Column: Dionex IonPac AG16,
AS16, 4 mm
Flow rate: 1.0 mL/min
Eluent:
65 mmol/L KOH
Eluent
Source:
Dionex EGC III KOH
Perchlorate
µS
B. Second Dimension Conditions
Column: Dionex IonPac AS20,
0.4 mm
Flow rate: 10 µL/min
Eluent:
35 mmol/L KOH
—— Brand A bottled water (263 ng/L perchlorate) Eluent
Dionex EGC-KOH
—— Brand B bottled water (38.5 ng/L perchlorate) Source:
(Capillary)
—— 30 ng/L perchlorate in DI water
—— DI water
-1.0
30
Minutes
45

67. Conclusion
• The hydroxide-selective RFIC Dionex IonPac AS19 column was
specifically developed for the determination of trace bromate and
other disinfection byproduct anions in drinking and bottled water.
• It can be successfully used in place of the Dionex IonPac AS9-HC for
validating EPA Methods 300.1 (B), 317, and 326.
• A RFIC system and a Dionex IonPac AS19 column improves the
determination of bromate by increasing:
• Sensitivity
• System automation
• Ease of use
• The use of 2D-IC preserves performance even in high-matrix
samples.
* U.S. EPA Office of Water, Nov. 19, 2002