Facile Synthesis of Water Soluble, Fluorescent DNA-Polymer Conjugate via Enzymatic Polymerization for Cell Imaging

Over the couple of decades scientific community has witnessed the robust utilization of DNA as soft template for the directed growth of conducting polymers and the so formed DNA-conducting polymer hybrid finds wide application in various biomedical fields. Herein, we have employed DNA templated enzymatic polymerization technique to prepare water soluble, biocompatible, fluorescent DNA-polymer hybrid having boronic acid moiety utilizing the berberine intercalated fluorescent DNA. To achieve the DNA templated polymerization of 3-aminophenylboronic acid (APBA), catalytic property of the enzyme, horseradish peroxidase (HRP) is exploited in presence of hydrogen peroxide (H₂O₂). Fluorescence property is induced within this DNA-polymer conjugate, using the excellent intercalating propensity of berberine (B) towards base pairs of DNA. This synthesized fluorescent DNA- berberine-polymer conjugate (DBPAB) has effectively been employed as a cell imaging probe, owing to the presence of boronic acid groups having cell adhesive property. In addition, cellular uptakes as well as cell viability (evaluated using MTT assay) of DBPAB have also been investigated.