Skip to main content
. 2021 Aug 26;12:5138. doi: 10.1038/s41467-021-25391-z

Fig. 1. Design and fabrication of an implantable miniaturize optical fiber device (IMOD) for on-demand drug delivery and tumor impedance measurement.

Fig. 1

a The cross-section image of an uncoated optical fiber with embedded electrodes for measuring tumor impedance. PC, polycarbonate; PVDF, polyvinylidene difluoride. b Procedure for coating the optical fiber surface with hydrophobic molecules (e.g., verteporfin or rhodamine) and filling the inner channel of the fiber with hydrophilic drugs (e.g., immune checkpoint blockade (ICB) antibodies or fluorescein isothiocyanate–bovine serum albumin (FITC-BSA)). The obtained fiber was assembled with an integrated-circuit (IC) chip to the IMOD device. c An image of IMOD with a refilling tubing and IC chip. d IMOD combines photodynamic therapy, immune checkpoint therapy, and impedance measurement, thus allowing for monitoring of treatment efficacy and adjustment of the antibody dosage to generate a sustained anti-tumor immune response while minimizing systemic toxicities. e Fluorescence imaging of an optical fiber coated with rhodamine B (red) and loaded with FITC-BSA (green). Scale bar: 500 µm. Data are representative of three repeated experiments. f Implantation of IMOD into a subcutaneous E0771 tumor in a C57BL/6 mouse. g Connection of IMOD in (f) via an electrical connector to a Gamry potentiostat for impedance measurement.