3
visit
Figure2
Analyte levels in samplesareunknown; only inert columns,whichprevent
concentration fromaffecting retention time, canassureaccurate results.
Figure3
AnRxi columngives
thebestoverall performance
forbothbasicandacidic
compounds.
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 responseand
predictable retention times.
HP-5ms
ImprovedResponse forDifficultCompounds
Another reason column inertness is important for trace-level analysis is thatmany acidic, basic, and polar
compounds will tail significantly and become difficult to analyze if the column contains active sites. The
remarkableneutralityofRxi®columns solves thisproblemandallowsawiderangeof compounds tobeana-
lyzedwith high sensitivity, often on a single column. All Rxi® columns are exceptionally inert as demon-
strated in Figure 3 by high response factors for both pyridine (basic) and 2,4-dinitrophenol (acidic). Rxi®
columns reliably produce highly symmetric peaks and improved responses for difficult compounds, indi-
cating greater inertness than columns producedbyothermanufacturers (Figure 4).
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
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 integrationand
additional 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
2ngpyridine
2ng2,4-dinitrophenol
Column
Column
ResponseFactor (RF)
ResponseFactor (RF)
Comparisonof 30m x0.25mm ID,
0.25μm columns.
Innovation&Service
"Whenmy research group
needed aGC column for a chiral
separation, Restekwas the only
company that offered toprovide
uswith test columns to evaluate.
Thewillingness of Restek to
workwithus 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.
Website :
E-mail :
TelNo : 03 9762 2034 . . . inAUSTRALIA
