Contents
明朝为什么会灭亡I. IntroduCtIon
II. InstallatIon and eQuIlIBratInG tHe ColuMn幸福的终点
a. Preparation
要红包图片
b. Installing the Column
c. Equilibration
III. PreParatIon oF eluents and saMPles
a. Preparing the Eluent
b. Sample Preparation and Filtration
IV. oPeratIon
a. Chromatography Guidelines
b. Efficiency Testing
c. Eluent Preparation
d. Standard Preparation
V. Care and MaIntenanCe
a. Troubleshooting
b. Cleaning and Regenerating the Column
c. Column Storage
VI. orderInG InForMatIon
VII. warranty/rVICe InForMatIon I. IntroduCtIon
Waters IC-Pak™ Ion Exclusion columns provide a durable column bed for repetitive analys at high nsitivities. The columns are nominal 7 µm, spherical, fully sulfonated resin.
The Ion Exclusion columns are available in 7.8 mm diameter, in both the 150 mm and the 300 mm formats. The columns are shipped in a solution of 10 parts methanol and 90 parts water.
Plea take a few moments to read this manual carefully. The recommen-dations contained here will help you maximize column lifetime and help you obtain the most reproducible chromatographic results.
彩陶图片waters IC-PaK™ Ion eXClusIon ColuMns
II. InstallInG and eQuIlIBratInG tHe ColuMn
a. Preparation
Before attaching a new column in the flow path:
1. Directly connect the HPLC injector to the detector by replacing
the of column with a zero-dead-volume union.
2. Flush the lines to remove any microparticulates and old
solvents. Flush the injector loop, if applicable.
3. Remove the union.
b. Installing the Column
Remove the compression screws from your column with a 5/16-inch wrench and save them for u when storing the column. Initially attach the column so that flow follows the direction of the arrow on the column label.
Note: The IC-Pak Ion Exclusion column actually can be ud in either flow direction.
Procedure
To install the column, thread the inlet and outlet fittings into the column until finger tight, and then tighten the fittings 1/4 to 1/2 turn. A properly prepared and asmbled compression fitting will al if the instructions are followed.
Note: Do not over-tighten; this will damage the connection.
Note: The critical distance between the end of the ferrule and the end of the tubing may differ for different column types. If this is the ca, make up a new full (Figure 1) using tubing with an internal diameter of 0.009-inch. Tubing of this diameter should be ud for all lines between the injector and detector for the best analytical chromatography.
Figure 1. Ferrule and Compression Screw Asmbly When the Seal is Poor
Occassionally, a ferrule may not form an effective al. Do not try to over-tighten the fitting. To replace a worn reffule or damaged screw, u the following procedure:
1. Using file with a cutting edge, or a tubing cutter, scribe
the circumference of the tubing at the desired break.
2. Grasp the tubing on both sides of the scribe mark with cloth
covered pliers (to prevent marring the tubing surface), and
gently work the tubing back and forth until it parates.
Note: Ensure that the tubing end is straight, open, and free of burrs.
3. Slide the compression screw fitting, followed by the ferrule
(large end of the taper first) over the tube (Figure 1).
Note: Properly bottom the tubing in the fitting at. If the
tubing is not completely ated, the resulting dead volume can lead to poor chromatographic results.
c. Equilibration
The Ion Exclusion column is shipped in 10% methanol and requires equilibration with the test eluent or mobile pha prior to u.
Procedure
To equilibrate the column:
1. Connect the column to your system.
2. Equilibrate with the desired eluent for 10 minutes at
0.5 mL/min to remove most of the methanol.
3. Ramp to 1.0 mL/min in 60 conds, allowing the pump
pressure to stabilize between 0.1 mL/min increments.
4. Maintain the flow at 1.0 mL/min for 20 minutes, or until
the baline is stable, and proceed with your analysis. If the
baline does not stabilize, check the other components of your LC system.
III. PreParatIon oF eluents an saMPles
a. Preparing the Eluent
Follow the guidelines when preparing eluents:
⏹Recommended eluents are dilute aqueous solutions of acids.
Note: The high concentrations (more than 20%) of organic sol-
vents in the mobile pha will impair column performance. Also avoid amines, metals, and corrosives such as hydrochloric acid
(HCI).
⏹Filter eluents to remove microparticulate matter using a
filter of 0.45 µm porosity, or smaller. U ultrapure water
(18 megohm resistivity), such as that supplied by the Milli-Q®
reagent grade water system.
⏹U vacuum filtration and/or sonication to remove dissolved
gas which could affect your pump.
⏹U a Waters in-line precolumn filter to capture any particulates斤斤计较的人
that may have entered the system.
b. Sample Preparation and Filtration
If the sample contains dissolved contaminants or particulates that may bind irreversibly to the column, follow one of the procedures:
⏹U a Waters Sample Clarification Kit, to filter samples and电磁炉和电陶炉
prevent the high back pressures that result from blocked column inlets.
⏹U Sep-Pak® cartridges to remove contaminants from the
sample that may adsorb on the packing material surface, caus-
ing changes in chromatographic performance and reduced
column lifetime.
⏹U a Waters Guard-Pak™ holder, along with IC-Pak Ion Exclusion
Guard-Pak inrts, to adsorb both chemical and physical
contaminants. IV. oPeratIon
a. Chromatorgraphy guidelines
Liquid chromatography columns have a finite lifetime which ss directly related to the care and u they receive. Column life is reduced by contamination from samples and eluents, frequent eluent changeover and improper handling and storage.
Adopting some of the simple procedures outlined in this and the previous ction can extend column
lifetime.
If you obrve a change in peak shape, retention of a particular com-pound, or resolution between two compounds, take immediate steps to determine the reason. Until the cau of the change is determined, do not rely upon the results of the analys.
Note: Before running the first analysis on your new column, perform the test sample paration given in Section IV. b.
Guidelines
The following operating guidelines will help you obtain the best performance from the Waters analytical HPLC column:
⏹Do not exceed an operating pressure of 13 MPa (130 atm or
2,000 psi).
⏹Filter all eluents. Never u turbid or cloudy mobile phas.
⏹Protect the column from vibration, mechanical shock, and rapid
changes in pressure, which can result from rapidly changing the composition of the eluent.
⏹When using water as a mobile pha component, u water
which has been purified with a Milli-Q water system capable
of delivering 18 megohm water. Neither deionized water nor
bottled HPLC-grade water are acceptable, becau they contain organic compounds which may after column lectivity.
b. Efficiency Testing
Waters columns are tested for adherence to our specifications using the sample, mobile pha, and flow rate detailed in Table 1. Slight variations in your results will occur depending on:
⏹Condition of the equipment ud
⏹Test sample makeup
⏹Equipment ttings and conditions (such as flow rate or composition).
Initial Efficiency Test
Before attempting the first analysis, perform an initial efficiency test. To do this, run the test sample using the following procedure and record the results and instrument ttings:
1. Equilibrate the column with the appropriate mobile pha at
the desired flow rate.
2. Record the retention time, the instrument ttings, and the
system configuration so the conditions can be reproduced exactly for future comparison.
Measuring Efficiency
Waters us the 5 sigma method, shown in Figure 2, to measure column efficiency. Unlike the tangent method, this more stringent method considers naturally occurring peak asymmetry.
If problems occur during normal operation of the column, repeat the efficiency test and compare the results. This may help identify the source of the problem.
Figure 2. 5 Sigma Test Method
N = Column efficiency (plates) VR = Volume to peak apex (ml)W = Volume at 4.4% of peak height (ml)
Test Conditions
Table 1 lists the conditions Waters us to check the efficiency of IC-Pak Ion Exclusion columns. Figure 3 is a reprentative chromato-gram of flouride and short-chain weak organic acids.
Table 1. Column Test Conditions
Figure 3. Chromatogram of Fluoride and Short-chain Weak Organic Acids
Working Standard
Fluoride 1 ppm Acetate 5 ppm Formate 5 ppm Propionate 5 ppm Butyrate 5 ppm
Eluent:
1 mM Octanesulfonic Acid Pump: 590 Solvent Delivery Module Injector: 710B WISP
Column:
Ion Exclusion (300 mm X 7.8 mm) Data: 840 Data System Flow Rate: 1.0 mL/min
Injection: 100 µL of Working Standard Detection: 430 Conductivity Range: 500 µS
Temperature: On
Polarity:
+
Background:
320 µS
c. Eluent Preparation
10 mM Octanesulfonic Acid Concentrate
1. To a 254 mL beaker add
黑枸杞子的功效与作用
2.163 g of the sodium salt of
octane sulfonic acid (98% Aldrich) and dissolve in 100 mL
Milli-Q water.
2. Add 100 mL of precleaqned cation exchange resin in the
H+ form (BloRad AG 50W-X12, 200-400 mesh, or equiva-
lent) and stir in the resulting slurry for 10 minutes.
3. Filter the resin, rinsing with approximately 800 mL of
Milli-Q water, into a one liter volumetric flask. Dilute up to
the mark with Milli-Q water.
Note: This 10 mM oc tanesuffonic acid solution istable for at least
one month.
1 mM Octanesulfonic Acid Eluent (pH3)
1. Into a one-liter volumetric flask add 100 mL of the octane-
sulfonic acid concentrate.
2. Fill the flask to the mark with Milli-Q water and mix
thoroughly.
3. Filter and degas through a 0.45 µm HA filter.The H+ ion from the acid influences the paration. The acid’s counter-anion has no effect but to after the background conductivity. Thus, other strong acids can be substituted for octanesulfonic acid.
Note: Acid Normality should be kept constant.
Weak organic acids can also be detected by direct UV absorption in the 205 nm to 215 nm range.
d. Standard Preparation
1. Prepare 1000 ppm stock standards from their sodium salts
2. For this working standard, dilute:
0.1 mL of 1000 ppm Fluoride
0.5 mL of 1000 ppm Formate
1.0 mL of 1000 ppm Acetate
1.0 mL of 1000 ppm Propionate
1.0 mL of 1000 pnm Butyrate
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Note: This working standard should be prepared weekly, since the
formate concentration decreas with time.
