Fabrication of the CNTs/NiAl–LDH nanocomposite as a carrier of a luminescent sensor for DNA detection

A novel fluorescent sensor based on CNTs/NiAl−LDH nanocomposite and Ru(phen)3Cl2 could selective detect DNA with detection limit of 6.09 × 10−8 g/mL. [Display omitted] •LDH combined with CNTs was used as a sensor material for DNA detection for the first time.•A significant hybrid material of CNTs/NiAl-LDH was successfully prepared via one-step homogeneous precipitation approach.•The DNA sensor prepared by CNTs/NiAl-LDH has high sensitivity and low detection limit. Since the 21st century, nanocomposites based on layered double hydroxide (LDH) and carbon nanotubes (CNTs) are extensively employed as heat stabilizers, supercapacitors and electrocatalysts, due to their high conductivity, outstanding stability and environmental friendliness. Herein, CNTs/NiAl–LDH composite were obtained by one-step hydrothermal method and used as a platform for Ru(phen)3Cl2 (tris(1,10-phenanthroline)ruthenium (II) dichloride) sensor to selectively detect CT DNA (Calf thymus DNA). It was found that CNTs/NiAl–LDH composite could effectively quench the emission of the Ru(phen)3Cl2 sensor in aqueous solution. After adding a certain amount of CT DNA to the above system, the Ru(phen)3Cl2 interacted with CT DNA immediately and released from the CNTs/NiAl–LDH, resulting in the fluorescence recovery. In the concentration range of 4.4–26.3 μg/mL, the increase of luminescence was linearly proportional to the amount of CT DNA added, and the correlation coefficient was 0.9967. The detection limit was 6.09 × 10−8 g/mL.