Magnetic nanowires for rapid and ultrasensitive isolation of DNA from cervical specimens for the detection of multiple human papillomaviruses genotypes

Detecting human papillomavirus (HPV) is central in diagnosing and monitoring HPV-related disease. However, limited sensitivity and the wide variability of the HPV genome pose challenges in the identification of HPV genes, particularly high-risk types. This study reports the development of polyethyleneimine-conjugated magnetic nanowires (PEI-MNWs) and their use in the isolation, identification, and analysis of multiple genotypes of HPV DNA from cervical cancer specimens. The nanowires are electrochemically doped with a high density of magnetic nanoparticles and biotin moieties during potentiostatic deposition, thereby allowing conjugating cationic branched polymers to direct the attachment of negatively charged DNA molecules with strong magnetic response. For proof of concept, the rapid and ultrasensitive isolation of HPV DNA is performed at concentrations as low as 10 pg/mL with an efficiency of > 95%. For clinical optimization, the analytical and clinical sensitivity of PEI-MNWs is compared with that of the Roche Cobas 4800 HPV Test and demonstrates excellent correlation for multiple HPV DNA genotypes with superior threshold cycle values. The high sensitivity, specificity, and good reproducibility of PEI-MNWs are particularly well suited for the recovery of DNA and provide significant and clinically meaningful evidence for the early detection and treatment of HPV-associated cancers. (C) 2016 Elsevier B.V. All rights reserved.