This allows the injection needle to be wiped off.Дo you use Chemstation? We use Millennium32. I have bought some 5з„Ў syringes from Agilent and also plan to try out SGE's focus liners which have a small layer of quartz wool (they claim this has advantages over glass wool) that is held in place by a collar. Yes I realized that is part of the problem. We've had similar experience here when injecting aqueous solutions, so we changed those to 0.5 ul injection from a 5 ul syringe (change syringe configuration to 5 ul through software, then injection volume can be changed to 0.5 ul) 1 ul water expands to 1420 ul water vapor, too large for the 6890 liner volume. I think your problem is due to the injection volume, since your solvent is water which expands to greater volume than organic solvents. Sorry about the garbled stuff before the 0.1% - that was the less than or equal to sign The glycerin probably minimizes backflash.Д«y Ahalya Wise on Wednesday, Octo04:25 pm: I see better reproducibility for the diethylene glycol peak with solutions that contain the 5% w/v glycerin than with the aqueous solutions.

The sample: 1 з„Ў of 5%w/v aqueous solutions of glycerin spiked with various amounts of diethylene glycol at в‰¤ 0.1% of the glycerin concentration.

The standard: 1 з„Ў of a very dilute aqueous solution of diethylene glycol The system:HP6890 30mx0.53mm fused silica column with a 3з— film of Rtx-1301 He at a constant flow rate with an initial linear velocity of about 70 cm/s an FID at 250иљ“ split injection (split ratio is 0.1)with a 20ml/min pulse at 1 min and a 15 ml/min purge at 0.75min injection is at 220иљ“ temperature program: 100 to 220иљ“ at 5иљ“ per minute The problem: poor reproducibility for small impurity peaks Chromatography Forum Poor reproducibility probably due to flashbackД¬hromatography Forum: GC Archives: Poor reproducibility probably due to flashbackД«y Ahalya Wise on Wednesday, Octo04:23 pm:

Agilent chemstation gc injection volume