A
novel
method
of
separation
that
uses
water
as
a
stationary
phase
in
capillary
gas
chromatography
(GC)
is
presented.
Through
applying
a
water
phase
to
the
interior
walls
of
a
stainless
steel
capillary,
good
separations
were
obtained
for
a
large
variety
of
analytes
in
this
format.
It
was
found
that
carrier
gas
humidification
and
backpressure
were
key
factors
in
promoting
stable
operation
over
time
at
various
temperatures.
For
example,
with
these
measures
in
place,
the
retention
time
of
an
acetone
test
analyte
was
found
to
reduce
by
only
44
s
after
100
min
of
operation
at
a
column
temperature
of
100
◦
C.
In
terms
of
efficiency,
under
optimum
conditions
the
method
produced
about
20,000
plates
for
an
acetone
test
analyte
on
a
250
m
i.d.
×
30
m
column.
Overall,
retention
on
the
stationary
phase
generally
increased
with
analyte
water
solubility
and
polarity,
but
was
relatively
little
correlated
with
analyte
volatility.
Conversely,
non-polar
analytes
were
essentially
unretained
in
the
system.
These
features
were
applied
to
the
direct
analysis
of
different
polar
analytes
in
both
aqueous
and
organic
samples.
Results
suggest
that
this
approach
could
provide
an
interesting
alternative
tool
in
capillary
GC
separations
Anovelmethodofseparationthatuseswaterasastationaryphaseincapillarygaschromatography(GC)ispresented.Throughapplyingawaterphasetotheinteriorwallsofastainlesssteelcapillary,goodseparationswereobtainedforalargevarietyofanalytesinthisformat.Itwasfoundthatcarriergashumidificationandbackpressurewerekeyfactorsinpromotingstableoperationovertimeatvarioustemperatures.Forexample,withthesemeasuresinplace,theretentiontimeofanacetonetestanalytewasfoundtoreducebyonly44safter100minofoperationatacolumntemperatureof100◦C.Intermsofefficiency,underoptimumconditionsthemethodproducedabout20,000platesforanacetonetestanalyteona250mi.d.×30mcolumn.Overall,retentiononthestationaryphasegenerallyincreasedwithanalytewatersolubilityandpolarity,butwasrelativelylittlecorrelatedwithanalytevolatility.Conversely,non-polaranalyteswereessentiallyunretainedinthesystem.Thesefeatureswereappliedtothedirectanalysisofdifferentpolaranalytesinbothaqueousandorganicsamples.ResultssuggestthatthisapproachcouldprovideaninterestingalternativetoolincapillaryGCseparations
การแปล กรุณารอสักครู่..

A
novel
method
of
separation
that
uses
water
as
a
stationary
phase
in
capillary
gas
chromatography
(GC)
is
presented.
Through
applying
a
water
phase
to
the
interior
walls
of
a
stainless
steel
capillary,
good
separations
were
obtained
for
a
large
variety
of
analytes
in
this
format.
It
was
found
that
carrier
gas
humidification
and
backpressure
were
key
factors
in
promoting
stable
operation
over
time
at
various
temperatures.
For
example,
with
these
measures
in
place,
the
retention
time
of
an
acetone
test
analyte
was
found
to
reduce
by
only
44
s
after
100
min
of
operation
at
a
column
temperature
of
100
◦
C.
In
terms
of
efficiency,
under
optimum
conditions
the
method
produced
about
20,000
plates
for
an
acetone
test
analyte
on
a
250
?
m
i.d.
×
30
m
column.
Overall,
retention
on
the
stationary
phase
generally
increased
with
analyte
water
solubility
and
polarity,
but
was
relatively
little
correlated
with
analyte
volatility.
Conversely,
non-polar
analytes
were
essentially
unretained
in
the
system.
These
features
were
applied
to
the
direct
analysis
of
different
polar
analytes
in
both
aqueous
and
organic
samples.
Results
suggest
that
this
approach
could
provide
an
interesting
alternative
tool
in
capillary
GC
separations
การแปล กรุณารอสักครู่..
