One-step enzyme-free dual electrochemical immunosensor for histidine-rich protein 2 determination.

Ariamna María Dip Gandarilla,Matias Regiart,Juliane Correa Glória,Luís André Morais Mariuba,Mauro Bertotti,Walter Ricardo Brito

doi:10.1039/d0ra08729g

Abstract

In the present work, we describe a novel one-step enzyme-free dual electrochemical immunosensor for the determination of histidine-rich protein 2 (Ag-PfHRP2), a specific malaria biomarker. A gold electrode (GE) was functionalized with the PfHRP2 antibody (Ab-PfHRP2) using dihexadecyl phosphate (DHP) polymer as an immobilization platform. The Ab-PfHRP2/DHP/GE sensor was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy, and atomic force microscopy. The developed immunosensor was employed for indirect Ag-PfHRP2 determination by differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). The linear range was 10–400 ng mL−1 and 10–500 ng mL−1 for EIS and DPV, while the limit of detection was 3.3 ng mL−1 and 2.8 ng mL−1, respectively. The electrochemical immunosensor was successfully applied for Ag-PfHRP2 determination in human serum samples. Its performance was compared with an ELISA test, and good correspondence was achieved. The coefficients of intra- and inter-assay variations were less than 5%. The electrochemical immunosensor is a useful and straightforward tool for in situ malaria biomarker determination.

Highlights

Malaria is one of the most important tropical infectious parasitic diseases, caused by Plasmodium sp. parasites (Plasmodium falciparum, ovale, vivax, malariae, and knowlesi) and transmitted by the female of Anopheles mosquito
According to the World Malaria Report 2019, there was an estimate of 405 000 deaths globally in 2018, and the infections by Plasmodium falciparum parasite are the most common.[1]
Nucleic acid ampli cation tests have been used to detect the nucleic acid of the malaria parasite, including aDepartment of Chemistry, Federal University of Amazonas, Manaus, Amazonas 69067-005, Brazil

Summary

Introduction

Malaria is one of the most important tropical infectious parasitic diseases, caused by Plasmodium sp. parasites (Plasmodium falciparum, ovale, vivax, malariae, and knowlesi) and transmitted by the female of Anopheles mosquito. According to the World Malaria Report 2019, there was an estimate of 405 000 deaths globally in 2018, and the infections by Plasmodium falciparum parasite are the most common.[1] The morbidity and mortality are higher in low resource populations, with limited health care facilities.[2]. Malaria diagnosis is commonly con rmed by microscopic examination, which consists of the observation of blood samples on a microscopic slide assisted with staining. Such an approach requires trained professionals, specialized facilities, long analysis time, expensive equipment, and reagents.[3] Nucleic acid ampli cation tests have been used to detect the nucleic acid of the malaria parasite, including

Methods

Results

Conclusion