Highly sensitive detection of faropenem using amino functionalized carbon nanotube modified electrode with ionic liquid as binder: Insight into the interaction of faropenem with human serum albumin

• [MWCNT-NH2]/IL modified electrode showing highly sensitive to FAR was constructed.
• The anodic peak current of FAR was remarkably enhanced by [MWCNT-NH2]–IL modified GCE.
• A simple and sensitive electrochemical method was developed for detection of FAR.
• The sensor was successfully applied in clinical analysis with satisfied results.
• FAR–HSA interaction was studied by electrochemistry and spectroscopy.

A simple, rapid and sensitive electroanalytical detection method for faropenem (FAR) using amino-functionalized multi-walled carbon nanotubes (MWCNT-NH2) and ionic liquids (IL) 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) modified glassy carbon electrode (GCE) was developed. Compared with bare electrode, [MWCNT-NH2]–IL modified electrode significantly enhanced the oxidation peak current of FAR, suggesting that the modified electrode can remarkably improve the determining sensitivity of FAR. Electrochemical studies suggested that the [MWCNT-NH2]–IL composite system provided a synergistic augmentation effect on the voltammetric behavior of electrochemical oxidation of FAR. Under the optimum conditions, this constructed biosensor exhibited two linear relationships with FAR concentration range from 5.6 × 10−7 to 2.8 × 10−5 mol/L and 3.3 × 10−5 to 1.6 × 10−4 mol/L, respectively. The detection limit was 3.1 × 10−8mol/L (S/N = 3). The proposed method can satisfy the detection of FAR in routine clinical analysis. The fabricated electrode has been successfully applied to the determination of FAR in real samples and exhibited good reproducibility, stability and anti-interference. Moreover, the electrochemical method and spectroscopy method are also used to study the interaction between FAR and human serum albumin (HSA). The binding constant and the number of binding sites between FAR and HSA obtained by electrochemical method were consistent with the fluorescence analysis.