Targeted 8-arm PEG Nanosystems for Localization of Choroidal Neovascularization Macular Degeneration Model.

8-arm PEG (polyethylene-glycol) is a highly promising nanoplatform due to its small size (<10 nm), ease-of-conjugation (many functionalized variants are readily available with "click-like" properties), biocompatibility, and optical inactivity. This study evaluates 8-arm PEG uptake into cells () and localization and clearance in vasculature () for targeting of choroidal neovascularization in mice, an animal model of macular degeneration. 8-arm PEG nanoparticles were labeled with fluorescein isothiocyanate (FITC) and functionalized in the absence or presence of pentameric Ar-Gly-Asp (RGD; 4 RGD motifs and a PGC linker), one of the most common peptide motifs used for active targeting.

Photoacoustic lifetime oxygen imaging of radiotherapy-induced tumor reoxygenation .

Purpose: Early detection and diagnosis of cancer is critical for achieving positive therapeutic outcomes. Biomarkers that can provide clinicians with clues to the outcome of a given therapeutic course are highly desired. Oxygen is a small molecule that is nearly universally present in biological tissues and plays a critical role in the effectiveness of radiotherapies by reacting with DNA radicals and subsequently impairing cellular repair of double strand breaks.

Photoacoustic Chemical Imaging Sodium Nano-Sensor Utilizing a Solvatochromic Dye Transducer for In Vivo Application.

Sodium has many vital and diverse roles in the human body, including maintaining the cellular pH, generating action potential, and regulating osmotic pressure. In cancer, sodium dysregulation has been correlated with tumor growth, metastasis, and immune cell inhibition. However, most in vivo sodium measurements are performed via Na NMR, which is handicapped by slow acquisition times, a low spatial resolution (in mm), and low signal-to-noise ratios.

Photoacoustic Spectral Analysis for Evaluating the Aggressiveness of Prostate Cancer Labeled by Methylene Blue Polyacrylamide Nanoparticles.

Evaluating the aggressiveness of prostate cancer (PCa) is crucial for PCa diagnosis and prognosis. Previously, studies have shown that photoacoustic spectral analysis (PASA) can assess prostate tissue microarchitecture for evaluating the aggressiveness of PCa. In this study, in a transgenic mouse (TRAMP) model of PCa, we utilized methylene blue polyacrylamide nanoparticles (MB PAA NPs) to label the cancer cells in prostate in vivo.

Personalized Oncology by In Vivo Chemical Imaging: Photoacoustic Mapping of Tumor Oxygen Predicts Radiotherapy Efficacy.

We hereby apply the approach of photoacoustic chemical imaging, performing an in vivo chemical analysis that is spatially resolved (200 μm) and in real time, to predict a given tumor's response to therapy. Using triple negative breast cancer as a model, we took photoacoustic images of tumors' oxygen distributions in patient-derived xenografts (PDXs) in mice using biocompatible, oxygen-sensitive tumor-targeted chemical contrast nanoelements (nanosonophores), which function as contrast agents for photoacoustic imaging. Following radiation therapy, we established a quantitatively significant correlation between the spatial distribution of the initial oxygen levels in the tumor and its spatial distribution of the therapy's efficacy: the lower the local oxygen, the lower the local radiation therapy efficacy.