Functionalisation data of a carbon electrode biosensor for detection of antimicrobial resistance

The fabrication process involves multi LTCC layers, and screen printing of silver reference electrode (RE), carbon layer of working electrode (WE) and counter electrode (CE), and the dielectric layers. The SPCEs were functionalised with a specific (Peptide nucleic acid) PNA probe, by electrografting through in situ generated diazonium cations. Then creating a 4-carboxyphenyl (AP) film on the electrode surface after the modification of SPCEs electrochemical by reduction of the in situ generated 4-carboxyphenyl diazonium salt, using four cyclic voltammetry (CV) scans from +0.4 to -0.6 V at a scan rate of 100mV/s. The AP film then activated via 60 min incubation in 1-Ethyl-3-(3-Dimethylaminopropyl)Carbodiimide (EDC) and NHS (N-hydroxysuccinimide) in a MES (2-(Nmorpholino) EthaneSulfonic acid), PH 5.0. After, the electrode surface rinsed in MES buffer, and incubated it in amino-modified PNA probe dispersed in droplet of PBS buffer for 60 min at room temperature. Formation of a blocking film by droplet deposition to the electrode of 1% v/v ethanolamine/PBS buffer and incubated for 30 min in room temperature. Finaly, 52 min incubation with complimentary DNA target and electrochemical impedance spectroscopy (EIS) measurements by (Metrohm-Autolab, PGSTAT204/FRA32M), (dRCT 100kHz to 0.3Hz) in a 1mM KCl + 2mM Ferri/Ferrocyanide solution. DNA strand hybridizing to probs lead to an accumulation of negative charge on the electrode surface causing an increase in the charge transfer resistance (RCT).