Multifunctional Polymeric Nanoparticles for Chemo/Phototheranostics of Retinoblastoma.

Retinoblastoma (Rb) is the most critical and severe intraocular malignancy occurring in children. The clinical management of retinoblastoma is still challenging due to failure in early detection and control despite the advancements in medical strategies. Early-stage Rb tumors do not occupy major visual fields, so chemo/photothermal therapy (PTT) with biocompatible materials can be a practical approach. Herein, we report multifunctional polymeric nanoparticles (PNPs) entrapped with an FDA-approved anticancer drug, Palbociclib (PCB), and a near-infrared dye, IR820 (IR), as chemo/photothermal agents. These PCB/IR PNPs were evaluated for the combinational effect in the retinoblastoma cell line. Further, the in vivo photoacoustic imaging efficacy and acute toxicity profile of the PNPs were studied in a mice model. The results indicated that the PCB/IR PNPs exhibited a significant cytotoxic effect (86.5 ± 2.3%) in Y79 cell lines than the respective control groups upon exposure to NIR light. Qualitative and quantitative analyses indicated that PCB/IR PNPs with NIR light induction resulted in DNA damage followed by apoptosis. PCB/IR PNPs, when tested in vivo, showed optimal photoacoustic signals. Thus, the combination of PCB and PTT can emerge as a translational modality for retinoblastoma therapy.

Cross-linked chitosan biofunctionalized paper-based microfluidic device towards long term stabilization of blood typing antibodies.

Long term stability of antibodies at room temperature is a major challenge in the commercialization of point-of-care devices for diagnostics. Since chitosan has been proven to be an excellent biofunctionalization material, the effects of four different biofunctionalization processes were studied to improve the room temperature stability of antibodies immobilized on chitosan modified paper-based microfluidic devices using blood typing antibodies as candidates. The devices used in this work have a flower-shaped design with 4 test zones at each corner. In three zones Anti-A, Anti-B, and Anti-D (Anti-Rh) antibodies are immobilized and the fouth zone represents the control (no antibodies) after biofunctionalization. The biofunctionalization of the paper devices was done with chitosan and chitosan cross-linked with sodium triphosphate pentabasic, glutaraldehyde, and sodium hydroxide. These devices were used for blood typing assays using real blood samples. A similar assay was also performed on unmodified (non-biofunctionalized) paper devices for comparison. Chitosan based biofunctionalized paper-devices showed better stability, up to 100 days as compared to 14 days on unmodified paper, at room temperature. Such biofunctionalized paper-based devices will be suitable for on-field and remote testing without any technical expertise and requirement for the cold chain.