A DNA Biosensor Based on a Raspberry-like Hierarchical Nano-structure for the Determination of the Anticancer Drug Nilotinib

Abstract

It is crucial to design fast, sensitive and affordable deoxyribonucleic acid (DNA) recognition instruments, and elucidate changes in DNA structure, for studying the interaction between DNA and chemotherapy drugs. Therefore, a DNA biosensor, based on a carbon paste electrode (CPE), modified with raspberry-like indium(III)/nickel oxide hierarchical nano-structures (In³⁺ /NiO RLHNSs) was constructed. An electrochemical readout should then give information on the interactions between anticancer drugs and double-stranded (ds)-DNA. The morphology as well as the electrochemical description of this new biosensor is described. Based on experimentally determined optimal conditions, ds-DNA modified with In³⁺ /NiO RLHNSs/CPE was used to evaluate the binding interaction of nilotinib, as an anti-cancer drug, with DNA through differential pulse voltammetry (DPV), UV-Vis spectroscopy, viscosity measurements and a computational docking process. The analyses indicated the linearity of the guanine oxidation signal at nilotinib concentration is given between 0.01 and 50.0 μm, with the limit of detection (LOD) equal to 0.62 nm. Additionally, the equilibrium constant (K) for the binding was determined to 1.5×10⁴ m^-1 . Through the quantitative measurement of nilotinib in serum samples with a high recovery rate of 101.3-98.0 %, the applicability of this approach was demonstrated. As a whole, this DNA biosensor may be promising for various bio-interactions.

Keywords: carbon paste electrode; hierarchical nanostructure; indium; nilotinib; sensor.

Figure 1

(A) FESEM image and (B) high‐resolution FESEM image of In³⁺/NiO RLHNSs.

Figure 2

(A) Cyclic voltammograms of 5 mm [Fe(CN)₆]^3−/4− in 0.1 m KCl: (a) CPE, (b) NiO RLHNSs/CPE (c) In³⁺/NiO RLHNSs/CPE, (d) ds‐DNA/In³⁺/NiO RLHNSs/CPE. Scan rate: 50 mV s⁻¹; (B) Nyquist plots of (a) CPE, (b) NiO RLHNSs/CPE (c) In³⁺/NiO RLHNSs/CPE, (d) ds‐DNA/In³⁺/NiO RLHNSs/CPE in 0.1 m KCl containing 5.0 mm [Fe(CN)₆]^3−/4−.

Figure 3

(A) The oxidation signal plot of guanine vs. ds‐DNA concentration (2.0–25.0 mg L⁻¹); (B) the oxidation signal plot of guanine in different accumulation time of ds‐DNA (50–300 s); (C) influence of incubation time of 50.0 μm nilotinib in ABS (0.1 m, pH 4.8) on the response of ds‐DNA/In³⁺/NiO RLHNSs/CPE.

Figure 4

Differential pulse voltammograms of guanine after the interaction between 0.0, 5.0, 15.0, and 25.0 μm nilotinib in ABS (0.1 m, pH 4.8) (curves a–d, respectively) and ds DNA at ds‐DNA/In³⁺/NiO RLHNSs/CPE.

Figure 5

Voltammograms of ds‐DNA/In³⁺/NiO RLHNSs/CPE for different concentrations of nilotinib in ABS (0.1 m, pH 4.8). From top to bottom (1–14), 0.0, 0.01, 0.5, 1.0, 5.0, 10.0, 15.0, 20.0, 25.0, 30.0, 35.0, 40.0, 45.0 and 50.0 μm; (B) dependence of the net oxidation guanine current (different between guanine current in the absence and presence of nilotinib) vs. concentration of nilotinib.

Figure 6

The oxidation current diagram of ds‐DNA/In³⁺/NiO RLHNSs/CPE in the presence of 10.0 μm nilotinib in ABS (0.1 m, pH 4.8) and other investigated interferences.

Figure 7

(A) UV‐vis absorption spectra of nilotinib (15.0 μm) in the absence and presence of the ds‐DNA, the numbers 1–6 correspond to 5.0, 10.0, 20.0, 30.0 and 40.0 μm. (B) The plot of A₀/A‐A₀ vs. 1/[ds‐DNA].

Figure 8

Effect of increasing amount of nilotinib on the relative viscosity of ds‐DNA in ABS (pH 4.8).

Figure 9

(A) Nilotinib‐DNA minor groove interaction; (B) and (C) geometrical disposition of nilotinib in DNA minor groove, green round dot show the hydrogen bonds between nilotinib and DNA.