Microfabricated potentiometric sensor based on a carbon nanotube transducer layer for selective Bosentan determination

Abstract

In this work, a solid-state electrochemical sensor relying on potentiometric transduction was constructed and optimized to detect Bosentan (BOS) in its pharmaceutical dosage form and human plasma. BOS is useful in pulmonary hypertension management as a nonselective endothelin receptor antagonist. A printed circuit board has been constructed and used as a substrate for microfabricated Cu electrodes. In comparison to a microfabricated control (Cu/ISM) electrode, the sensor potential signal drift was enhanced, and the response time was reduced by using multi-walled carbon nanotubes (MWCNTs) as an ion-to-electron transducer layer. According to IUPAC requirements, the suggested BOS sensors have been electrochemically characterized, and the linear dynamic range is (1.0 × 10−8 to 1.0 × 10−5) M with a limit of detection of 6.28 × 10−9 M and 6.12 × 10−9 M for MWCNT-based sensor (Cu/CNT-NC/ISM) and control sensor (Cu/ISM), respectively. The described sensors have been used successfully to selectively determine BOS in dosage form and human plasma without any pre-treatment steps.

Keywords

• bosentan
• microfabricated sensors
• solid-contact electrodes
• carbon nanotubes
• ion-to-electron transducer