Impedimetric DNA Sensor Based on Poly(proflavine) for Determination of Anthracycline Drugs

Abstract

Electropolymerization is often used as a tool for immobilization of charged biopolymers and their electric wiring in the biosensor assembly. In this work, electropolymerization of proflavine has been for the first time used for the physical adsorption of DNA and measurement of anthracycline drugs (doxorubicin and daunorubicin) able to intercalate DNA. Redox properties of the proflavine polymers on the glassy carbon electrode and DNA deposition were characterized with cyclic voltammetry, scanning electron microscopy and electrochemical impedance spectroscopy. It was shown that DNA decreased the peak currents on voltammogram but increased the charge transfer resistance. The latter effect is pronounced with the following drug application. The impedimetric response regularly increased with the drugs concentration in the range 1 nM to 0.1 μM for doxorubicin and 1 pM–10 nM for daunorubicin (limit of detections 0.3 and 0.001 nM, respectively). The biosensor was tested on pharmaceutical preparations and spiked solution simulating the plasma electrolytes and possible interference of serum proteins.

Electrochemical DNA Sensor Based on the Copolymer of Proflavine and Azure B for Doxorubicin Determination

“…However, the Azure B peak pair at low potentials remained on voltammograms during the whole period of potential cycling (20 cycles) whereas the anodic irreversible peak was decreased with the number of cycles similarly to that observed here for the mixture of dyes. Regarding proflavine [31], it formed quasi-reversible pair of the peaks with the peak potential difference (0.22 and −0.13 V) higher than that discussed above for the Azure B polymer and the Azure B-proflavine copolymer. In this pair, cathodic peak was slowly increased with the number of potential cycles and anodic one was quite stable.…”

“…Polyelectrolyte complexes of the redox active polymers and DNA have been successfully applied for the detection of specific biochemical interactions of the DNA influencing redox equilibria of the support [3]. For this purpose, polyaniline [42], poly(Neutral red) [27,43], poly(Methylene blue) [43], poly(Methylene Green) [43], poly(Azure B) [29], and poly(proflavine) [31] have been used. In this work, the DNA solution was applied on the working surface of the electrode covered with the copolymer and either dried or left capped with plastic tube preventing drying for a certain time.…”

“…In comparison with individual dyes, which electropolymerization was studied earlier, the surface morphology is similar to that of proflavine. The latter one also forms aggregates covered with roundish particles [29], whereas poly(Azure B) had a uniform structure with elongated parallel inclusions [31].…”

“…Recently, other derivatives of the phenazine dyes (Azure A, Azure B) and proflavine able to change their electrochemical properties in the presence of the proteins and DNA have been introduced in the electroanalysis [29][30][31][32]. Thus, proflavine, an acridine dye, was successfully used for the detection of the DNA hybridization events due to the ability to intercalate double-stranded DNA helix and to influence the electron exchange conditions on the electrode interface [33].…”

“…Azure B was electropolymerized on the Pt and glassy carbon electrode (GCE) in acidic media [30] and polycrystalline Au [35] showing reversible redox behavior both in monomeric and polymeric form. The only examples of the application of the polymeric proflavine and Azure B in the assembly of the DNA sensors were done in our previous works [29,31], where rather low efficiency of the electropolymerization referred to the low solubility of the monomers in neutral media.…”