i have no peak

[chemgirl00]

hi i have problems about my peaks. i injected system suitability solution first, everything is okay and started sample set. but couldn't dedect any peak. system is gradient and flow: 0,27. i checked everything and as same as methods.
waiting your suggestions..

[bunnahabhain]

I suggest that you give more information:
What system, what system suitability samples, what eluent, what detector, ...

[chemgirl00]

System HP 1100, column;C18,150 x 2.0 mm 3µm, Flow:0,27 and gradient, Detection: 200nm,i connected two columns serial.system conditions like this. when i saw peaks started immediately set but where is gone my peak, i didn' t know

[BostonFSE]

Possible reasons for no peak:
your purge valve on the pump is open
You selected the wrong wavelength
Your sample volume in vial is too low
You have air in your system (purge all lines for 5 min each)
Your method run time is too short, peak is still on column

[chemgirl00]

purge valve off i'm sure. only not sample, and standard i didn't see peak. purged my system. system was high pressure. i tried analysis shimadzu system but didn't work because of high pressure. this peaks wasn't seen; because of high pressure?