Developing a nanomaterial-based 3D-printed platform

Abstract

Overexpressed heat shock protein 90 (HSP90) has been proven as a new cancer biomarker, and its detection can be used as an auxiliary diagnosis. In this research, we designed an electrochemical aptasensor to detect this biomarker. Initially, a 3D-printed electrode was designed and produced while the electrode surface (made from a conductive carbon black/ polylactic acid (CB-PLA) filament) was improved by CO2 laser ablation. Then, the electrode surface was modified with graphene oxide (GO) and an array of frost-like gold nanocrystals (FGNCs); the results showed that the final surface covered with gold contained nano/microstructures with a mean width of ∼ 65 nm and a mean length of ∼ 509 nm. Also, a significant increase in the electrochemically active surface area was observed for modified surfaces with GO and FGNCs. Efficient immobilization of aptamer strands on the gold surface could complete the assembly of this aptasensing platform, which could detect analyte molecules in a linear range from 0.1 to 200 ng mL−1. The estimated limit of detection (LOD) and the limit of quantification (LOQ) were as low as 0.1 ng mL−1 and 0.23 ng mL−1, respectively. The performance of reproducibility (5 times), regeneration (5 times), and stability (7 days) were satisfactory (low relative standard deviation (RSD)). Also, this aptasensor showed adequate performance for selective and accurate analyte capturing in the presence of interfering agents and spiked analyte concentrations in serum samples.