Nanomaterials and DNA multistranded structures: a treasure hunt for targeting specific biomedical applications

The advent in nanoscience and nanotechnology has enabled the successful synthesis and characterization of different nanomaterials with unique electrical, optical, magnetic and catalytic activities. However, with respect to sensing applications, nanomaterials intrinsically lack target recognition ability to selectively bind with the analyte. DNA, an important genetic material carrying biopolymer is polymorphic in nature and shows structural polymorphism, forming secondary/multistranded structures like hairpin, cruciform, pseudoknot, duplex, triplex, G-quadruplex and i-motif. Studies reported so far have suggested that these polymorphic structures have been targeted specifically for the treatment or diagnosis of various diseases. DNA is widely used in conjugation with nanomaterials for the development of nanoarchitectures due to its rigidity, sequence programmability and specific molecular recognition, which makes this biomolecule a treasure for designing of DNA based frameworks. These two entities (DNA and nanomaterials) can be used in association with each other, as their alliance can result into creation of novel assay platforms for different purposes, ranging from imaging, sensing and diagnostics to targeted delivery. In this review, we have discussed about the recent reports on association of various mutistranded/ polymorphic forms of DNA with nanomaterials. Furthermore, different applications using this versatile DNA-nanomaterial assembly has also been elaborated at length. This review aims to target the interests of scientists from various interdisciplinary fields, including biologists, chemists and nanotechnologists, who wish to gain an understanding of nano-fabrications using a plethora of DNA polymorphic forms.Communicated by Ramaswamy H. Sarma.