One-pot fabrication of GA-functionalized Cu-nanoparticles by pulsed laser ablation for electrochemical biosensors development

Functionalized nanoparticles (NPs) are widely used in nanobiosensor fabrication providing improved selectivity and good conductivity. Synthesis of functional nanomaterials is often costly and typically requires several functionalization steps. In this work, we used Pulsed Laser Ablation in Liquids (PLAL) to synthetize and functionalize at the same time copper (Cu) NPs with glutamic acid (GA). A Cu target immersed in a GA solution and hit by a laser led to Cu ablation, NP formation and amine groups bonding at the NPs surface. The GA-functionalized Cu NPs were immobilized onto an electrode and linked to antibodies for alpha-synuclein protein. A successful protein detection was achieved through electrochemical impedance spectroscopy (EIS) measurements at concentration in the pg/mL range. A careful optimization of NP synthesis showed an improved experimental LoD (10 pg/mL) by varying the amount of GA- Cu NPs and the PLAL environment, demonstrating this one-pot fabrication of GA-functionalised Cu-nanoparticles by PLAL as a valuable method for high sensitivity electrochemical sensing electrode.