fig12

Figure 12. Electrochemical aptamer-based tobramycin sensors for minimally invasive therapeutic drug monitoring. (A) Schematic illustration of a MN patch applied to a rodent model, together with stained histological images showing penetration marks remaining in the skin after MN insertion; (B) Raw SWV recorded from rat ISF; (C) Real-time pharmacokinetic profile extracted from noisy raw voltammograms through algorithmic signal processing; (D) Schematic overview of an AuNP-coated MN-EAB patch designed for minimally invasive ISF microsampling and efficient signal transduction; (E) Tobramycin sensing response of the MN-EAB platform compared with that of a standard gold disk EAB sensor. The inset shows raw SWV acquired over a tobramycin concentration range of 0-100 µM; (F) Response of the MN-EAB sensor to 10 µM tobramycin during repeated insertion into porcine skin tissue, demonstrating the mechanical robustness of the electrochemical interface under repeated sampling conditions. (A-C) Reproduced with permission Copyright 2022, Analytical Chemistry^[131]. (D-F) Reproduced with permission Copyright 2022, Science Advances^[226]. MN: Microneedle; SWV: square wave voltammetry; ISF: interstitial fluid; AuNP: Au nanoparticle; EAB: electrochemical aptamer-based; PDMS: polydimethylsiloxane; RE: reference electrode; WE: working electrode; CE: counter electrode; μNEAB: microneedle-based electrochemical aptamer biosensing; Disc-Au: gold disk electrode.