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The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) has emerged as a promising strategy for cancer treatment. However, the poor photostability and photothermal conversion efficiency (PCE) of organic small-molecule photosensitizers, and the intracellular glutathione (GSH)-mediated singlet oxygen scavenging largely decline the antitumor efficacy of PTT and PDT. Herein, a versatile nanophotosensitizer (NPS) system is developed by ingenious incorporation of indocyanine green (ICG) into the PEGylated chitosan (PEG-CS)-coated polydopamine (PDA) nanoparticles via multiple π-π stacking, hydrophobic and electrostatic interactions. The PEG-CS-covered NPS showed prominent colloidal and photothermal stability as well as high PCE (ca 62.8 %). Meanwhile, the Michael addition between NPS and GSH can consume GSH, thus reducing the GSH-induced singlet oxygen scavenging. After being internalized by CT26 cells, the NPS under near-infrared laser irradiation produced massive singlet oxygen with the aid of thermo-enhanced intracellular GSH depletion to elicit mitochondrial damage and lipid peroxide formation, thus leading to ferroptosis and apoptosis. Importantly, the combined PTT and PDT delivered by NPS effectively inhibited CT26 tumor growth in vivo by light-activated intense hyperthermia and redox homeostasis disturbance. Overall, this work presents a new tactic of boosting antitumor potency of ICG-mediated phototherapy by PEG-CS-covered NPS., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Chemodynamic therapy (CDT) has emerged as a promising strategy for tumor treatment. Nevertheless, the low Fenton catalytic efficiency and the high concentration of glutathione (GSH) in cancer cells largely decline antitumor efficacy of CDT. To self-augment antitumor effect of the CDT by combining with photothermal therapy (PTT), the unique photothermal nanozymes that doubly depleted GSH, and generated massive hydroxyl radicals (·OH) in the hyperthermia/acidity-activated manner were developed. Through the coordination of Fe 3+ ions with PEGylated chitosan (PEG-CS)-modified polydopamine (PDA) nanoparticles, the attained Fe 3+ @PEG-CS/PDA nanozymes showed outstanding colloidal stability, photothermal conversion efficiency and acidity-triggered Fe 3+ release. By GSH-mediated valence states transition of Fe 3+ ions and Michael reaction between GSH and quinone-rich PDA, the nanozymes sufficiently executed dual depletion of GSH with the elevated temperature.Under mimic tumor acidity and near-infrared (NIR) irradiation condition, the endocytosed nanozymes effectively converted intracellular H 2 O 2 into toxic ·OH upon amplified Fenton reaction, thereby potently killing 4T1 cancer cells and RAW 264.7 cells. Importantly, the nanozymes prominently suppressed 4T1 tumor growth in vivo and metastasis of cancer cells by CDT/PTT combination therapy without significant systemic toxicity. Our study provides novel visions in design of therapeutic nanozymes with great clinical translational prospect for tumor treatment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Nanoparticles were designed to encapsulate drugs to alter their pharmacological behaviors, therefore, it is very essential to monitor the pharmacokinetic profile of drug encapsulated in nanoparticles in order to clarify and predict their efficacy and side effects. In this paper, we reported a simple, rapid μ-elution 96-well solid phase extraction (μSPE) method combining with ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for determination of nanoformulated drug in rat plasma. This method presented satisfactory results in terms of sensitivity, precision, accuracy, and recovery, for the first time, of quantitatively analyzing clarithromycin (CLA) in rat plasma after intravenous administration CLA-loaded ultrafine PLGA nanoparticles for pharmacokinetic study. This method has been proved to be fast, reliable and reproducible to accurately analyze drug encapsulated in polymeric nanoparticles sample for a pharmacokinetic study., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Glial cell line derived neurotrophic factor (GDNF) induces neuronal survival and tissue repair after spinal cord injury (SCI). A continuous GDNF supply is believed to gain greater efficacy in the neural restoration of the injured spinal cord. Accordingly, nanovehicle formulation for their efficient delivery and sustained release in injured spinal cord was examined. We first used fluorescence-labeled bovine serum albumin (FBSA) loaded in biodegradable poly(lactic acid-co-glycolic acid) (PLGA) for intraspinal administration after SCI and for in vitro study. Our results showed that the preservation of PLGA-FBSA was observed in the injured spinal cord at 24h, and PLGA-FBSA nanoparticles were well absorbed by neurons and glia, indicating that PLGA as a considerable nanovehicle for the delivery of neuroprotective polypeptide into injured spinal cord. Furthermore, intraspinal injection of GDNF encapsulated in PLGA (PLGA-GDNF) nanoparticles into the injured spinal cord proximal to the lesion center had no effect on gliosis when compared to that observed in SCI rats receiving PLGA injection. However, local administration of PLGA-GDNF effectively preserved neuronal fibers and led to the hindlimb locomotor recovery in rats with SCI, providing a potential strategy for the use of PLGA-GDNF in the treatment of SCI.

In our study, the dye-sensitized solar cells (DSSCs) with double-layer thin films were fabricated. The active bottom layer of the structure was mainly made of the commercially available titanium dioxide (TiO2) nanoparticles. TiO2 hollow microspheres (THS) were doped into the TiO2 composite material and used as the scattering top layer. The THS prepared by the one-pot hydrothermal method was composed of irregularly arranged nanoparticles. Meanwhile, we also characterized the synthesized hollow TiO2 microspheres by both the scanning electron microscope (FE-SEM) and the X-ray diffractometer (XRD). Besides, we produced DSSCs with different weight percentages (0.5wt%, 1wt%, and 2wt%) of THS photoanodes. The DSSCs based on pure TiO2 showed the short-circuit current (JSC) of 8.33 mA/cm2 and the photovoltaic conversion efficiency (PCE) of 3.75%. The DSSCs manufactured using 1wt%-THS photoanode had JSC of 12.02 mA/cm2 and a PCE of 5.01%. When compared with the JSC and PCE based on pure TiO2 DSSCs, a significant improvement in the structure was observed. [ABSTRACT FROM AUTHOR]