Hi, I am new at purification using HPLC. Trying to purify about 300mg of a peptide using agilent 1100 hplc. I swapped the analytical c18 column 25mc x 4.6mm 5um with a preparative c18 column 15cm x 22mm 5um. Unfortunately Agilent 1100 pump only goes up to 5ml/min and the ourification column specs are at 10ml/min! I decided to shot 100uL of 1% peptide sample in water and run a H2O/ACN gradient at 3ml/min, only to find out theflow cell is leaking. How could a 1100 be converted to purification column. How can I know when to collect the fraction if the flow cell leaks after 3ml/min?

Also I could inject up to 1ml with agilent 1100 bt the sample loop is only 900uL capacity. Is this going to cause a problem?
Any help appreciated.