Sample Injection Method - Hitachi CHROMASTER 5160 Instruction Manual

2.3.2 Sample Injection Method

Summary
Measurement
method
Measurement
method details
Reproducibility
Sample loss
Carry over
Injection time
The loop
exchange when
the injection
volume is
changed
Injection range
Commingling of
wash fluid with
flow path
AS dead volume
as system
The decline of
the sample
concentration
caused by
influences of
dilution (the
diffusion).
(1) Description of each method
Select a sample injection method for the Chromaster 5210
autosampler from the following three methods.
Table 2-1
Cut Injection Method
(Standard)
The amount of sample
withdrawn by the needle
is slightly larger than the
amount that will be
transferred from the
injection valve to the
column. The middle
part of the sample is
injected; the leading and
trailing ends are not
injected.
This method provides
good reproducibility,
however some of the
sample is wasted.
Syringe
Discharge rate from
Syringe
○
△ (occurrence)
○
○
◎ (unnecessity)
◎ (broad)
◎ (nonoccurence)
○
△ (90% to 98%)
Injection Methods
All Volume Injection
Method
The entire sample
withdrawn by the needle
is transferred to into the
sample loop and into the
column.
This method is suitable
for analysis of minute
samples since no part of
the sample is washed.
Syringe
Aspiration/Discharge
rate from syringe
△
◎ (nonoccurrence)
◎ (Low-volume
sample handling)
◎
◎ (unnecessity)
○ (narrow)
△ (occurrence)
○
△ (90% to 98%)
◎:Better, ○:Good, △:Acceptable
2 - 9
Full Loop
Injection Method
The sample loop is filled
with sample for
measurement.
This method provides
the best repeatability of
sample injection volume
in analysis.
Loop
The summation of the
capacity of the flow
pass in the loop and
the injection valve
◎
△ (occurrence)
○
◎
△ (necessity)
△ (fixity)
◎ (nonoccurence)
◎
○ (to 99 %)