Voltammetric hybridization assay for the β1-adrenergic receptor gene (ADRB1), a marker for hypertension, by using a metal organic framework (Fe-MIL-88NH2) with immobilized copper(II) ions

The β1 receptor blocker metoprolol targets the hypertension-carrying adrenergic receptor gene (ADRB1), but therapy is often hindered by a lack of evidence-based medical information. The authors describe an assay for the ADRB1 gene. It is based on the electrocatalytic oxidation of H 2 O 2 by a nanocomposite consisting of hemin and platinum nanoparticles in an amino-modified metal-organic framework of the type Fe-MIL-88-NH 2 and heavily loaded with Cu(II) ions. The nanocomposite was placed on a glassy carbon electrode (GCE), and the resulting sensor displays increased electrocatalytic activity with the addition of H 2 O 2 because of the synergistic effects of hemin and the platinum nanoparticles (Pt NPs). Next, a capture DNA probe for the target ADRB1 gene was immobilized on the modified GCE. Binding of the target gene results in a distinct change in the electrocatalytic activity of H 2 O 2 . The amperometric i–t curves were recorded at −0.4 V in 5 mL of phosphate buffered saline at room temperature. The electrode responds to ADRB1 in the 1 f. to 10 nM concentration range and has a 0.21 f. detection limit (at a S/N ratio of 3). In our perception, this detection scheme can simplify and accelerate the identification of drug response and therapeutic efficacy. Conceivably, it may be applied to other mutations, and it may enable a more precise clinical prognosis and thus facilitate personalized medical diagnostics. Schematic presentation of an electrode for the determination of the adrenergic receptor gene (ADRB1). The assay is based on the electrooxidation of added H 2 O 2 by using a glassy carbon electrode (GCE) coated with a composite prepared from platinum nanoparticles (Pt NPs), hemin and a metal-organic framewok of type Fe-MIL-88NH 2 loaded with Cu(II). This versatile platform simplifies studies on the response of hypertension drugs and the effectiveness of therapy.