An electrochemical immunoassay for neopterin was developed using recently produced specific antibodies immobilized to protein A-coated magnetic beads in combination with differential pulse voltammetry and screen-printed array of electrodes. Neopterin-alkaline phosphatase conjugate was used as label in a competitive assay format. Multiplexed analysis of neopterin was demonstrated by replacing the traditional ELISA with electrochemical detection and the traditional plastic wells with screen-printed array of electrodes. The optimized electrochemical method, based on polyclonal antibodies, reached a limit of detection of 0.008 ng/mL with an average RSD %=10. Serum samples collected from patients with sepsis, healthy volunteers and other patients without a confirmed clinical diagnosis were also analyzed. The obtained results, compared with those of a commercial ELISA kit, had a significant correlation, showing the possibility to distinguish among the serum samples from ill or healthy subjects.

Department of Biotechnology Veterinary Research Institute Hudcova 70 621 32 Brno Czech Republic

Istituto di Fisica Applicata Nello Carrara Consiglio Nazionale delle Ricerche Via Madonna del Piano 10 50019 Sesto Fiorentino Italy

Istituto di Fisiologia Clinica Consiglio Nazionale delle Ricerche Via G Moruzzi 1 56124 Pisa Italy

Università degli Studi di Firenze Dipartimento di Chimica Via della Lastruccia 3 50019 Sesto Fiorentino Italy; Istituto di Biochimica delle Proteine Via P Castellino 111 80131 Napoli Italy

Università degli Studi di Firenze Dipartimento di Scienze Biomediche Sperimentali e Cliniche Viale G Pieraccini 6 50139 Firenze Italy

References provided by Crossref.org

Magnetic nanoparticles for smart electrochemical immunoassays: a review on recent developments