Molecularly Imprinted Electrochemical Sensor-Based Fe2O3@MWCNTs for Ivabradine Drug Determination in Pharmaceutical Formulation, Serum, and Urine Samples

Fatehy M Abdel-Haleem; Eman Gamal; Mahmoud S Rizk; Adel Madbouly; Rasha M El Nashar; Badawi Anis; Hussam M Elnabawy; Ahmed S G Khalil; Ahmed Barhoum

doi:10.3389/fbioe.2021.648704

Molecularly Imprinted Electrochemical Sensor-Based Fe₂O₃@MWCNTs for Ivabradine Drug Determination in Pharmaceutical Formulation, Serum, and Urine Samples

Front Bioeng Biotechnol. 2021 Apr 8:9:648704. doi: 10.3389/fbioe.2021.648704. eCollection 2021.

Authors

Fatehy M Abdel-Haleem^{1

2}, Eman Gamal¹, Mahmoud S Rizk¹, Adel Madbouly¹, Rasha M El Nashar¹, Badawi Anis³, Hussam M Elnabawy⁴, Ahmed S G Khalil^{4

5}, Ahmed Barhoum^{6

7}

Affiliations

¹ Chemistry Department, Faculty of Science, Cairo University, Giza, Egypt.
² Cairo University Centre for Environmental Hazards Mitigation, Environmental Studies and Research, CHMESR, Cairo University, Giza, Egypt.
³ Spectroscopy Department, National Research Centre, Giza, Egypt.
⁴ Environmental and Smart Technology Group (ESTG), Faculty of Science, Fayoum University, Faiyum, Egypt.
⁵ Materials Science and Engineering Department, School of Innovative Design Engineering, Egypt-Japan University of Science and Technology (E-JUST), New Borg El-Arab City, Egypt.
⁶ NanoStruc. Research Group, Chemistry Department, Faculty of Science, Helwan University, Cairo, Egypt.
⁷ National Centre for Sensor Research, School of Chemical Sciences, Dublin City University, Dublin, Ireland.

Abstract

Ivabradine hydrochloride (IVR) is a medically important drug because of its ability to lower the heart rate. Techniques reported for IVR determination were expensive, laborious, besides being of poor selectivity. In this study, iron oxide @ carbon nanotube (Fe₂O₃@MWCNTs) nanocomposite and molecularly imprinted polymer (MIP) were synthesized and used in the fabrication of carbon paste electrodes (CPEs) for the potentiometric detection of IVR in biological and pharmaceutical samples. CPEs of the best sensor were formulated from graphite (41 wt%) as a carbon source, MIP (3 wt.%) as an ionophore, Fe₂O₃@MWCNTs (5 wt%) as a modifier, and nitrophenyl octyl ether (NPOE, 51 wt.%) as a conductive oil so-called plasticizer. The best sensor exhibits a Nernstian slope (response) of 56 mV decade^-1 within the IVR concentration range from 1.0 × 10^-3 M to 9.8 × 10^-8 M with high selectivity against interfering species (ascorbic, maltose, glucose, lactose, dopamine, glycine) over those reported earlier. The use of Fe₂O₃@MWCNTs together with MIP in the electrode formulation was found to improve the limit of detection (LOD) from 630 to 98 nM along with high reversibility, a short response time of 30 s, and a good lifetime of more than 2 weeks. The sandwich membrane (SMM) method was used to quantify the H-bonding complexing strength of the MIP binding sites for IVR with Log β _ILn = 11.33. The constructed sensors were successfully applied for the IVR determination in blood serum, urine, and commercial formulations (Savapran^®) with high sensitivity.

Keywords: H-bonding complexing strength; carbon paste electrodes; detection limit; formation constant; lifetime; molecularly imprinted polymers; reversibility; selectivity against interfering species.