What is the purpose of the PCR product purificationSolution

What is the purpose of the PCR product purification?

Solution

PCR product purification is necessary to get a single desiredPCR product (removal of non specific products) before ligation of PCR product into a plasmid or before giving it for sequencing. After a PCR reaction, it contains not only the PCR product but also many contaminants like non-incorporated nucleotides (dNTP), non specific amplification products, primer dimers, salts from buffer and unused primers as well as the enzyme DNA polymerase which was used during amplification stage of PCR. Before ligation, the PCR product is digested with restriction enzymes to generate sticky ends. DNA polymerase. if not removed, may add the remaining nucleotides to the complementary strand of the sticky end making it a blunt one. The remaining dNTP from the PCR reaction also changes the ratio of dNTP/ddNTP concentration (ddNTP is required for inhibition of DNA polymerase in DNA sequencing method) during sequencing reaction. Also, the salts in the buffer creates a problem during sequencing.