Localized Delivery of Theranostic Nanoparticles and High‐Energy Photons using Microneedles‐on‐Bioelectronics

The low delivery efficiency of light‐responsive theranostic nanoparticles (NPs) to target tumor sites, particularly to brain tumors due to the blood–brain barrier, has been a critical issue in NP‐based cancer treatments. Furthermore, high‐energy photons that can effectively activate theranostic NPs are hardly delivered to the target region due to the strong scattering of such photons while penetrating surrounding tissues. Here, a localized delivery method of theranostic NPs and high‐energy photons to the target tumor using microneedles‐on‐bioelectronics is presented. Two types of microneedles and flexible bioelectronics are integrated and mounted on the edge of surgical forceps. Bioresorbable microneedles containing theranostic NPs deliver the NPs into target tumors (e.g., glioblastoma, pituitary adenoma). Magnetic resonance imaging can locate the NPs. Then, light‐guiding/spreading microneedles deliver high‐energy photons from bioelectronics to the NPs. The high‐energy photons activate the NPs to treat tumor tissues by photodynamic therapy and chemotherapy. The controlled thermal actuation by the bioelectronics accelerates the diffusion of chemo‐drugs. The proposed method is demonstrated with mouse tumor models in vivo. Microneedle‐based local delivery of light‐responsive theranostic nanoparticles (NPs) and high‐energy photons to treat brain tumors is proposed. The multifunctional theranostic NPs are delivered locally using bioresorbable microneedles. Then, high‐energy photons generated from integrated bioelectronics are delivered by the light‐guiding/spreading microneedles to the NPs to activate photodynamic therapy/chemotherapy. The efficacy of the proposed treatment is demonstrated with two types of brain tumor model in vivo.