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Targeted drug delivery for primary brain tumors, particularly gliomas, is currently a promising approach to reduce patient relapse rates. The use of substitutable scaffolds, which enable the sustained release of clinically relevant doses of anticancer medications, offers the potential to decrease the toxic burden on the patient's organism while also enhancing their quality of life and overall survival. Upconversion nanoparticles (UCNPs) are being actively explored as promising agents for detection and monitoring of tumor growth, and as therapeutic agents that can provide isolated therapeutic effects and enhance standard chemotherapy. Our study is focused on the feasibility of constructing scaffolds using methacrylated hyaluronic acid with additional impregnation of UCNPs and the chemotherapeutic drug temozolomide (TMZ) for glioma treatment. The designed scaffolds have been demonstrated their efficacy as a drug and UCNPs delivery system for gliomas. Using the aggressive orthotopic glioma model in vivo , it was found that the scaffolds possess the capacity to ameliorate neurological disorders in mice. Moreover, upon intracranial co-implantation of the scaffolds and glioma cells, the constructs disintegrate into distinct segments, augmenting the release of UCNPs into the surrounding tissue and concurrently reducing postoperative damage to brain tissue. The use of TMZ in the scaffold composition contributed to restraining glioma development and the reduction of tumor invasiveness. Our findings unveil promising prospects for the application of photopolymerizable biocompatible scaffolds in the realm of neuro-oncology. [ABSTRACT FROM AUTHOR]

Biodegradable nanomaterials can significantly improve the safety profile of nanomedicine. Germanium nanoparticles (Ge NPs) with a safe biodegradation pathway are developed as efficient photothermal converters for biomedical applications. Ge NPs synthesized by femtosecond‐laser ablation in liquids rapidly dissolve in physiological‐like environment through the oxidation mechanism. The biodegradation of Ge nanoparticles is preserved in tumor cells in vitro and in normal tissues in mice with a half‐life as short as 3.5 days. Biocompatibility of Ge NPs is confirmed in vivo by hematological, biochemical, and histological analyses. Strong optical absorption of Ge in the near‐infrared spectral range enables photothermal treatment of engrafted tumors in vivo, following intravenous injection of Ge NPs. The photothermal therapy results in a 3.9‐fold reduction of the EMT6/P adenocarcinoma tumor growth with significant prolongation of the mice survival. Excellent mass‐extinction of Ge NPs (7.9 L g−1 cm−1 at 808 nm) enables photoacoustic imaging of bones and tumors, following intravenous and intratumoral administrations of the nanomaterial. As such, strongly absorbing near‐infrared‐light biodegradable Ge nanomaterial holds promise for advanced theranostics. [ABSTRACT FROM AUTHOR]

Förster resonance energy transfer (FRET) provides a unique means to probe processes occurring on the nanoscale. Efficient point-to-plane FRET between acceptors arrayed in two-dimensional (2D) sheets and point-dipole donors is known to exhibit an energy transfer proportional to d–4, where d is the distance from the donor to the acceptor-plane. We developed a 2D nanomaterial with surface-adjacent acceptors based on chromium-doped aluminum oxide (ruby) that supports 2D-FRET architecture. Ruby exhibits bright, narrow-band photoluminescence with a long lifetime and excellent photostability, and it was synthesized and processed to yield 2D ruby nanoflakes of 5 nm thickness, termed "rubyene". Rubyenes exhibit FRET with a remarkable efficiency of 96% as the donor paired with the acceptor indocyanine green (ICG) dye, exhibiting a distance dependence of d–n, where n varies from 4 to 6, as determined by the acceptor surface density. The dependence approaches d–4 in the limit of the acceptors' continuum distribution. The developed model of the random distribution of donor Cr3+ ions inside rubyenes and a discrete planar array of the acceptor ICG molecules in combination with high-density surface traps acting as nonresonant acceptors provides a nearly perfect fit to the experimental results and explains the emission lifetime variation from 5.8 to 0.7 versus the ICG surface density. We envisage potential applications of the demonstrated rubyenes for environmental sensing, optical labeling, FRET-scaled precision measurement, and engineered emission lifetime for multiplexed imaging. [ABSTRACT FROM AUTHOR]

Surgical resection is the main method for oral tongue squamous cell carcinoma (OTSCC) treatment. However, the oral physiological function and aesthetics may be seriously damaged during the operation with a high risk of recurrence. Therefore, it is important to develop an alternative strategy with precise guidance for OTSCC treatment. Herein, multifunctional Au/Mn nanodots (NDs) are designed and synthesized. They can perform multimodal bioimaging, including computed tomography (CT) and magnetic resonance imaging (MRI) simultaneously, and exhibit bright near-infrared fluorescence imaging (FI) for navigation, and even integrate photothermal therapy (PTT) property. The localization of OTSCC relies on visual and tactile cues of surgeons while lacking noninvasive pretreament labeling and guidance. Au/Mn NDs provide CT/MRI imaging, giving two means of accurate positioning pretherapy. Meanwhile, the fluorescence of the Au/Mn NDs in the near-infrared region (NIR) is beneficial for noninvasive labeling and intuitive observation with the naked eye to determine the tumor boundary during PTT. Further, Au/Mn NDs showed excellent results in ablating tumors in vivo. Above all, the Au/Mn NDs provide a key platform for multimodal bioimaging and PTT in a single nanoagent, which demonstrated attractive performance for OTSCC treatment. [ABSTRACT FROM AUTHOR]