INTRODUCTION The analysis of liquid samples can be done quite easily on the Exeter Analytical CE-440 analyzers without sacrificing accuracy or precision. By implementing the following procedure for handling liquid samples, all CE-440 users can now be assured of quality results. EQUIPMENT Exeter Analytical Capsule Sealer P/N 150-00054 Tin Capsules; 6x2.9 mm P/N 6703-0418 Nickel Sleeves; 7x3 mm P/N 6703-0412 Syringe, 10 ml P/N 318-00010 or Micropipette & Plunger Wiretrol, 5 ul PROCEDURE Place the tin capsule in a sturdy holder made of grease-free metal. Place the micropipette or syringe, with plunger fully inserted, into the liquid sample. Pull back on the plunger to draw liquid into the pipette or syringe (~2.5 ul is usually enough). Withdraw the micropipette or syringe from the liquid sample and insert it into the tin capsule so that the tip is resting on the bottom of the capsule. Be sure not to touch the inside walls of the tin capsule with the micropipette or syringe at any time during this procedure; this may lead to poor seal or allow volatile matter to coat the inside walls of the tin capsule above the seal. Press plunger down until an ample amount of liquid is in the capsule. Pull the micro pipette or syringe out of the capsule, again without touching the inside walls, and seal the capsule immediately with the Exeter Analytical Capsule Sealer or equivalent. Weigh the capsule on an ultra microbalance. If weight loss is observed over a short period of time, either seal the capsule with more force, or dispose of the capsule and repeat the sample loading procedure. Clean the syringe or dispose of the micropipette and clean the plunger with methanol and a dry tissue. Place the sealed capsule inside a nickel sleeve and proceed with the sample injection, or place the sample in the proper position on the HA-64 wheel. NOTES 1) Tin capsules are recommended over aluminum capsules in order to prevent trouble associated with capsule "jetting". 2) If aluminum capsules are used, (NOT recommended with the HA-64), be sure to place capsule on the ladle so that the crimped end is facing the combustion tube packings. This will aid the capsule in remaining on the ladle in case of "jetting". 3) When analyzing liquids for oxygen, silver capsules must be used (without nickel sleeves). If running an HA-64, the silver capsules must be run through the SSI port.

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