For High Performance Liquid Chromatography

Thank you for purchasing our COSMOSIL Packed Column. Ensuring maximum efficiency and long column life, we ask you to read this manual carefully.
COSMOSIL Packed Columns are made of stainless steel and packed with totally porous spherical silica-based materials. Our COSMOSIL series covers most of the conventional and special applications of normal phase chromatography, reversed phase chromatography and available for both analytical and preparative separation purposes. For the choice most suitable for your task consult with our distributor or contact directly Nacalai Tesque.


 1.Avoid mechanical shock.
 2.Connect the column according to the flow direction indicated on the label.
 3Let through the column 20-30ml mobile phase before connecting to the detector.
 4.Use scrupulously deaired mobile phase. Air bubbles generate detection noise and accelerate column deterioration.
 5.Use only HPLC grade solvents.
 6.Avoid precipitation in the column. Check the solvent constitution on the enclosed inspection record.
 7.Keep the pH of the mobile phase within the range of 2-7.5. Buffer concentration is usually sufficient within the range of 0.005-0.02M. Pass mobile phase through membrane filter (less than 0.5?m in pore size) before use. When using trifluoroacetic acid keep the concentration under 0.1%.
 8.Keep pressure under 200kgf/cm2. Take special care when using highly viscous mobile phase.
 9.After performing reversed phase chromatography, first wash the column with acid- and/or salt-free solvent, then with acetonitrile or methanol. Store it tightly plugged.
 10.After normal phase chromatography, change solvent to halogen free, non-polar (n-hexane or n-heptane). Keep the column tightly plugged.
 11.Filter the sample before injection. Avoid precipitation at injection.
 12.Removal of the end filters or change of the end-fittings will result in low performance of the column.
 13.Do not tighten nuts more firmly than necessary.
 14.Establish perfect chromatography conditions by experimenting with an analytical column of the same packing material before employing a preparative column. Pay attention to impurities without UV absorption or with longer retention time than your sample.


 1.In order to maximize the column performance, minimize the dead volume of mobile phase in the equipment by shortening and/or narrowing the width of tubing.
 2.Maintain constant column and tubing temperature.
 3.Avoid injecting air, changing flow rate rapidly and changing mobile phase at high flow rate.
 4.Insoluble matters from the pumping system, mobile phases, or samples trapped in the filter (2?m) at the inlet of the column may increase the pressure. Placing a 1?m prefilter between the injector and the column is highly recommended to prevent column clogging.
 5.Use guard column to protect both analytical and preparative type columns from irreversible adsorption on the packing material. Guard columns extend the lifetime of your valuable analytical and preparative columns.
 6.In normal phase chromatography pay attention to the change of retention time depending on the water content of the mobile phase or at injection of large amount of polar solvents.
 7.We recommend keeping the chromatography conditions constant, since frequent changes of mobile phase shorten column life.


increase of pressureclogging of the end filter
clogging of the packing material
precipitation in the column
(1) and/or (2)
poor resolutioncontamination of packing material
disorder of packing material
split peakvoid in the column
unstable baseline
(COSMOSIL PYE, NPE, Ph and PE type column)


 1.Disconnect column from the detector. Let mobile phase through the column in reverse direction at 0.5ml/min flow rate for 30 min.
 2.Wash the end filter or replace it with a new one.
 3.Wash the column with a solvent capable of dissolving the contaminants. The column can be washed, if necessary, with water, acetonitrile, methanol, ethanol, 1-propanol, 2-propanol, tetrahydrofuran, chloroform, n-hexane and n-heptane.
 4.Let through the column approximately 10ml tetrahydrofuran.


The strict quality control system of Nacalai Tesque supports the customers with an individual “Inspection Report” which accompanies each and every COSMOSIL and COSMOGEL Packed Column (except guard columns) and an additional “Certificate of Analysis” for the new COSMOSIL 5C18 MS-II and 5C18 AR-II (4.6mmID x150mm, 4.6mmID x 250mm).



Contains data of number of theoretical plates (N), peak asymmetry (s), capacity factor (k’) and separation factor (α).

N:theoretical plate number
TR:retention time
W1/2:peak half width
h:peak height
s:peak asymmetry
k’:capacity factor
α:separation factor



Validate terms of the physical properties of the silica gel, the carbon content, polar selectivity, hydrophobicity, silanol capacity steric selectivity, inactive degree to basic and chelating compounds.



Nacalai Tesque will change defective columns reported within 2 weeks of receipt. Nacalai Tesque approves return in case of:
(1) Damage during the transportation caused by our incomplete packing.
(2) Theoretical plate number measured according to the test method specified in the Inspection Report is significantly lower than guaranteed. (Please note that the plate number decreases when using apparatus with large dead volume or injecting big amount of sample.)
We cannot accept claims for deterioration of column performance caused by taking off the end filters or end-fittings, or long shelf life. Return shipment is unacceptable unless we have given prior permission and shipping instructions.


Learn more about Carbon 60 at SES Research