How to obtain a NICE GC Chromatogram with good peak profile?

To 1005ling: At the first look, seemingly found lots of impurities on the column.
(1) Did you condition the column according the GC Column manufacturer’s method? If No, Do IT now.
(2) If Yes, Double check that maybe your column was contaminated. Trim/cut the first 0.5 m of the inlet column or change another column.

If above tip doesn’t work, highly recommend you look back the Oven Temp Ramp: change the temp ramp by lowing down the initial temp, and hold for 5 min.

Or Double check the polarity different between your column and analyte.
Here is some information about the stationary phases of GC column with its applicability:
①SE-30: (100% Dimethylpolysiloxane), alternative to HP-1,HP-101, CP-si15CB,SPB-1, RTX-1,OV-1,007-1, ( similar with OV-101), is suitable for assay of amine, hydrocarbons, phenols, sulfides, flavor. Temperature Limits: 0 to 325/350°C.

② SE-52: (5%-Phenyl)-methylpolysiloxane. Or equivalent with SE-54.

③ SE-54: (5%-Phenyl)(1%-Vinyl)-methylpolysiloxane. Equivalent with HP-5,DB-5, CP-si18CB, RTX-5, OV-5, SPB-5,007-2 column. Good for assay of alkaloids, medicines, aliphatic acids, methyl ester, halide, aromatic. Temperature Limits: 0 to 350°C.

④ PEG-20M: are polymers of ethylene glycol, 20 meter. Highly cross-linked resulting in excellent peak. Alternative to HP-INNOWAX,HP-20M,CP-WAX52CB,DB-WAX,BP-20,007-CW for the assay of alcohol, aromatic, volatile oils, solvents. Temperature Limits: 0 to 250°C.

⑤ FFAP: Nitroterephthalic acid modified polyethylene glycol column. High polarity, Designed for the analysis of volatile fatty acids, ketone, nitrile and phenols. Bonded and cross-linked with solvent rinsable. Can be used at operating temperatures at 60-250ºC. Alternative to HP-FFAP, B-FFAP,CPWAX58CB,SP-1000,STABIL-PA,OV-351,007-FFAP Close equivalent to USP Phase G35.

⑥ XE-60: modified cyanoethylmethylpolysiloxane XE 60 (25% cya-. noethyl, 75% methyl)
Good for aliphatic acid，carborane, acryl amide, organophosphorus pesticides, cocaine, phenols, aromatic amine. Temperature Limits: 0 to 250°C.

⑦ OV-1701 : 14% cyanopropylphenyl-86% methyl polysiloxane. alternative to HP-1701,RTX-1701,SPB-7,SPB-1701,007-1701，good for environmental, food and beverages, pesticides, herbicides. Temperature Limits: 0 to 300 °C.

Reference: Phenomenex, Agilent, Restek Cross Reference for Similar GC Columns.

Note: Next time, pls enclose more detail of GC assay parameters, being a good questioner will help us answer well, NOT just guess. Thanks for your question, Best.