Problem with peaks shape

[drbraikeet]

Hi everybody
I have a GC-MSD 6890-5973 inert
It was used at PAH section in our lab and they had shifted it to my section which hormones analysis in food last week.
But after injection of my standards i had got peaks which have buildings shape not normal peaks.
Can anybody helping me to evaluate it and to find the problem from where and from which point
The concentration of my standards is 1ppb and it was derivatised by MSTFA.
So please help me and advice me.
I wish if i could post photo copy of it but i do not know how to iclude it in my post
Thanx a million for help.

[chromatographer1]

directions for inserting pics are found in the HPLC forum.

best wishes,

Rod

[Peter Apps]

We really need to see chromatograms.

If by "ppb" you mean ng/ml then on the assumption that you are injecting 1ul you only have 1pg of analyte. Unless you are doing something very clever I doubt that this will give you much of a peak.

Peter

[AICMM]

drbraikeet,

What is your scan rate and are you working in SIM or Scan? More info means more help.

Best regards,

AICMM

[drbraikeet]

Hi everybody
Sorry for not replying to the post
A friend had told me that the peak shapes i got either from the septum bleed or column bleed or may be from the inner liner may be it is damaged by any cause
I tooked it step by step
I had changed my septum and inner liner with new ones
the i had conditioned my column by passing a solvent ( start @ 70oC for 2 min then 5oC till 320oC for 10 min total will be 60 min) and repeat it for five times N.B. my MSD is off
then after connecting my column to the MSD i had pumped it down and bake it for 24 hours
after injecting my samples the peak shapes become normal
thats it
thank you everybody for every thing


N.B. still i can not find the way of including photocopy of my peaks and tune file