An ecofriendly iron MOF-based immunosensor for sensitive detection of vascular endothelial growth factor in the serum of cancer patients

Abstract

This work demonstrates the potential of an iron-based metal–organic framework, MIL-100(Fe), to effectively modify a multi-wall carbon nanotube (MWCNT) screen-printed electrode (SPE) for enhanced electrochemical immunosensing of vascular endothelial growth factor (VEGF), which has been recently considered a promising tumor biomarker. MIL-100(Fe) has been synthesized using an ecofriendly, sustainable, heatless water-based technique at various synthesis reaction times. The morphological, structural and electrochemical properties of the different samples of MIL-100(Fe) were evaluated using several physical and electrochemical techniques. MIL-100(Fe) after 48 h has a crystalline microporous–mesoporous structure, with superior properties, that is a larger BET surface area of 1082 ± 18 m² g⁻¹, a larger pore volume of 0.696 cm³ g⁻¹ and better electroconductivity. After optimizing the experimental conditions, the MIL-100(Fe) 48 h/MWCNTs/SPE-based immunosensor showed a linear range between 100 and 480 pg mL⁻¹, a LOD of 50 pg mL⁻¹ (3σ/S), a sensitivity of 0.017 mA mL pg⁻¹, good reproducibility and high selectivity. In addition, the developed immunosensor was used to satisfactorily detect VEGF in human serum samples of cancer patients, compared to the traditional ELISA method. Considering the sustainable and easy fabrication of the proposed platform, it may provide a promising application as a point-of-care (PoC) device for VEGF detection for diagnosis of cancer.