Which format is better when providing DNA sequencing samples?

We recommend customers to provide the bacteria and let us extract the plasmid to ensure purity and quantity of DNA samples. If the customer provides a DNA sample, we need to check the purity and quantity of samples. If the amount of DNA provided is insufficient, we need to amplify the plasmid. A conversion fee may be charged. The quality of DNA varies from different extraction methods. DNA purity and quantity should be checked when sequencing samples are PCR products. PCR products must be recovered by gel extraction, otherwise good sequencing results will not be obtained.