Comparison of testing methods for residual DNA in biotech drugs

Biotech drugs are drugs made by modern biotechnology with bioactive substances and their synthetic analogs, using biomass as raw materials. Biotech drugs, including cytokines, recombinant proteins, antibodies, vaccines, and oligonucleotides, have begun to be widely used clinically, and brought revolutionary change for the pharmaceutical industry. However, residual DNA in biological products may be potentially dangerous, so purification processes need to be validated to confirm its clearance. The new United States pharmacopoeia will recommend real-time quantitative PCR method be the only standard method for testing host residual DNA in biotech drugs. This method has the technical advantage of high specificity, high sensitivity, good reproducibility, and quantitative detection, making results more accurate, thereby provides a reliable means of detection in process research and product quality control for biopharmaceutical enterprises. This review compares 4 types of testing methods and focuses on two real-time quantitative methods. Key words: Drug evaluation; DNA contamination; Polymerase chain reaction; Fluorescent dyes; Oligonucleotide probes