Figure3
AnRxi®-5ms columngives
thehighest response forbothbasic
andacidiccompounds.
38
GCCOLUMNS |
HIGH-PERFORMANCERXI COLUMNS
Rxi® Columns Overview
ImprovedResponse forDifficultCompounds
Another reason column inertness is important for trace-level analysis is thatmany acidic,
basic, andpolar compoundswill tail significantlyandbecomedifficult toanalyze if the col-
umn contains active sites. The remarkable neutrality of Rxi® columns solves this problem
and allows awide rangeof compounds tobe analyzedwithhigh sensitivity, oftenon a sin-
gle column.All Rxi® columns are exceptionally inert as demonstrated in Figure 3 by high
response factors forbothpyridine(basic)and2,4-dinitrophenol (acidic).Rxi®columnsreli-
ably produce highly symmetric peaks and improved responses for difficult compounds,
indicatinggreater inertness than columnsproducedbyothermanufacturers (Figure4).
2.10 2.20 2.30 2.40 2.50 2.60 2.70 2.80 Time.
GC_EX01118
extracted ion chromatogram, m/z 79
GC_EX01119
2.25 2.30 2.35 2.40 2.45 2.50 2.55 2.60
Time.
A: Pyridineonnon-Rxi®column
Predictable retention
times, regardlessof
concentration; easy,
accurate integration.
B: Pyridineon-Rxi®column
Retention timesvarywith
concentration; poorpeak
shape requiresmanual
integrationandadditional
review.
10 ng, 2.26min.
2.5 ng, 2.28min.
1.0 ng, 2.32min.
10 ng, 2.39min.
1 ng, 2.40min.
0.5 ng, 2.41min.
0.000
0.200
0.400
0.600
0.800
1.000
Rxi-5ms
ZB-5
ZB-5MS
VF-5ms
HP-5ms
DB-5ms
DB-5
0.000
0.050
0.100
0.150
0.200
0.250
0.300
Rxi-5ms
ZB-5
ZB-5MS
VF-5ms
HP-5ms
DB-5ms
DB-5
2ngofpyridine
2ngof2,4-dinitrophenol
Column
Column
ResponseFactor (RF)
ResponseFactor (RF)
Comparisonof 30m x0.25mm ID, 0.25μm
columns.
Innovation&Service
“Whenmy research groupneeded a
GC column for a chiral separation,
Restekwas the only company that
offered toprovide uswith test
columns to evaluate. Thewillingness
of Restek toworkwithus to find a
solution toour separationproblem is
exceptional.”
JoeDinnocenzo,
ProfessorofChemistry
Director, Center for
PhotoinducedChargeTransfer
UniversityofRochester
Howcanwehelpyou today?
Contact
your
local Restek representative for helpful,
knowledgeable technical support.
Figure2
Analyte levels insamplesareunknown;only inertcolumns,whichpre-
ventconcentration fromaffecting retention time, canassureaccurate results.
Figure4
Rxi®columnsare themost inert columnson themarketproviding
themost symmetricpeak shape forbasiccompounds, suchaspyridine.
DB-5
ZB-5
ZB-5ms
Rxi
®
-5ms
DB-5ms
VF-5ms
Symmetricpeaksgivehigh response
andpredictable retention times.
HP-5ms
Comparison of 30m x 0.25mm ID, 0.25µm 5% diphenyl columns, 2ng pyridine on-column, helium carrier gas,
Oven temp.: 50°C (3min.) to 180°C@ 35°C/min. (5min.), Det.: FID@ 250°C
Website :
E-mail :
TelNo : 03 9762 2034 . . . inAUSTRALIA
Mar 2011
