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Persistent Luminescent Nanoparticles (PLNPs) emit prolonged light after excitation, allowing getting images with high signal‐to‐noise ratio, making them particularly beneficial for in vitro biodetection. In this study, we report the preparation of a library of gallium and zinc‐based Persistent Luminescent Nanoparticles doped with chromium (ZnGa2O4:Cr3+) through two distinct syntheses conducted at 120 °C for 12 hours or 24 hours, followed by a calcination at 500 °C or 750 °C. Using centrifugation, and starting from polydisperse samples, we demonstrated the ability to achieve different sizes in a monodisperse manner. Furthermore, our research revealed that ZnGa2O4:Cr3+ (ZGO) nanoparticles react differently with hydrogen peroxide (H2O2) based on their size, synthesis duration, and calcination temperature. We observed the most significant amplification of persistent luminescence for ZGO particles prepared at 120 °C for 12 hours and calcinated at 500 °C, with a size of approximately 100 nm, in the presence of 100 mM H2O2 (later named ZGO‐2). This study enabled the detection of H2O2 in serum without autofluorescence using the developed PLNPs, with a detection limit of up to 2.1 μM and a recovery rate of around 99 %. Additionally, we designed a glucose test for based on the responsiveness of ZGO PLNPs to H2O2. Using glucose oxidase, the glucose detection limit in serum was established around 0.13 μM, with a detection range between 0–5 μM. These findings could open new avenues to further control the size, synthesis, calcination temperature, and persistent luminescence of PLNPs, thus enhancing their utility in the development of new in vitro biosensors. [ABSTRACT FROM AUTHOR]

Age-related Macular Degeneration (AMD) is a multifactorial ocular pathology that destroys the photoreceptors of the macula. Two forms are distinguished, dry and wet AMD, with different pathophysiological mechanisms. Although treatments were shown to be effective in wet AMD, they remain a heavy burden for patients and caregivers, resulting in a lack of patient compliance. For dry AMD, no real effective treatment is available in Europe. It is, therefore, essential to look for new approaches. Recently, the use of long-chain and very long-chain polyunsaturated fatty acids was identified as an interesting new therapeutic alternative. Indeed, the levels of these fatty acids, core components of photoreceptors, are significantly decreased in AMD patients. To better understand this pathology and to evaluate the efficacy of various molecules, in vitro and in vivo models reproducing the mechanisms of both types of AMD were developed. This article reviews the anatomy and the physiological aging of the retina and summarizes the clinical aspects, pathophysiological mechanisms of AMD and potential treatment strategies. In vitro and in vivo models of AMD are also presented. Finally, this manuscript focuses on the application of omega-3 fatty acids for the prevention and treatment of both types of AMD. [ABSTRACT FROM AUTHOR]

Radiofrequency ablation (RFA) of cancer induces an anti-tumor immunity, which is insufficient to prevent recurrences. In mice, RFA–intratumoral immunotherapy by granulocyte–macrophage colony-stimulating factor (GM-CSF) and Bacillus Calmette-Guerin resulted in complete metastases regression. Infectious risk in human needs replacement of live vaccines. Intratumoral purified protein derivatives (PPD) have never been tested in digestive cancers, and the safety of intratumoral immunotherapy after RFA has not yet been validated in human models. We investigated the therapeutic efficacy of combined radiofrequency ablation (RFA) and intratumoral immunotherapy (ITI) using an immune-muco-adherent thermogel (IMT) in a mouse model of metastatic colorectal cancer (CRC) and the safety of this approach in a pig model. Intratumoral stability of the immunogel was assessed using magnetic resonance imaging (MRI) and bioluminescent imaging. Seventy-four CT26 tumor-bearing female BALB/c mice were treated with RFA either alone or in combination with intratumoral IMT. Regression of distant metastasis and survival were monitored for 60 days. Six pigs that received liver radiofrequency and intralesional IMT injections were followed for 15 days. Experimental gel embolisms were treated using an intravascular approach. Pertinent rheology of IMT was confirmed in tumors, by the signal stability during 3 days in MRI and 7 days in bioluminescence imaging. In mice, the abscopal effect of RFA–intratumoral immunotherapy resulted in regression of distant lesions completed at day 16 vs. a volume of 350 ± 99.3 mm3 in the RFA group at day 25 and a 10-fold survival rate at 60 days. In pigs, injection of immunogel in the liver RFA area was safe after volume adjustment without clinical, hematological, and liver biology disorder. Flow cytometry showed an early increase in CD3 TCRγδ+T cells at D7 (p < 0.05) and a late decrease in CD29+-CD8 T cells at D15 (p < 0.05), reflecting the inflammation status changes. Systemic GM-CSF release was not detectable. Experimental caval and pulmonary thermogel embolisms were treated by percutaneous catheterism and cold serum infusion. RFA–intratumoral immunotherapy as efficient and safe mini-invasive interventional oncology is able to improve ablative treatment of colorectal liver metastases. [ABSTRACT FROM AUTHOR]

After excitation in the biological transparency window, chromium-doped zinc gallate nanoparticles (ZGO NPs) emit near-infrared luminescence for more than an hour, allowing long-term imaging to be performed without background autofluorescence. However, these nanoparticles are recognized in just a few minutes by serum proteins and are then trapped in the liver. In this article, we put forth that liver uptake can be delayed when coating the surface of ZGO NPs with zwitterions. We focused on the use of a very small zwitterion molecule of 330 Da derived from sulfobetaine silane (SBS) and its grafting in one step and in water onto zinc gallate nanoparticles, and we compared the colloidal stability, the in vitro interactions with serum proteins, and the biodistribution in mice with PEGylated ZGO NPs (5000 Da) prepared in two steps in organic solvent. In vitro quantification of serum protein adsorption suggests that the similarity between the sulfobetaine and the cell membrane is enough to reduce protein adsorption as much as a PEGylation, despite the difference in coating thickness and molecular weight. This study has also proved that a combination of good protein repulsion and a smaller size compared to PEGylated NPs allows similar circulation times to be obtained in mice with zwitterionic or PEG coatings. Therefore, its use could offer new opportunities for further in vivo application of functionalized ZGO derivative NPs. [ABSTRACT FROM AUTHOR]

In the spirit of circular economy and sustainable chemistry, the use of environmentally friendly chemical products in pharmacy has become a hot topic. In recent years, organic solvents have been the subject of a great range of restriction policies due to their harmful effects on the environment and toxicity to human health. In parallel, deep eutectic solvents (DESs) have emerged as suitable greener solvents with beneficial environmental impacts and a rich palette of physicochemical advantages related to their low cost and biocompatibility. Additionally, DESs can enable remarkable solubilizing effect for several active pharmaceutical ingredients (APIs), thus forming therapeutic DESs (TheDESs). In this work, special attention is paid to DESs, presenting a precise definition, classification, methods of preparation, and characterization. A description of natural DESs (NaDESs), i. e., eutectic solvents present in natural sources, is also reported. Moreover, the present review article is the first one to detail the different approaches for judiciously selecting the constituents of DESs in order to minimize the number of experiments. The role of DESs in the biomedical and pharmaceutical sectors and their impact on the development of successful therapies are also discussed. [ABSTRACT FROM AUTHOR]

FOLFOX is the most common chemotherapy combination prescribed in colorectal cancer. It is composed of calcium levofolinate, 5-fluorouracil and oxaliplatin which demonstrated synergistic outcome. Nowadays, the lack of all-in-one formulation is due to the chemical composition of the pharmaceutical products and the highly pH-dependent stability of each drug. Herein, we aimed to investigate the stability of a ternary mixture of 5-fluorouracil, oxaliplatin and calcium levofolinate, knowing that coadministering these drugs would improve their efficacy. The effect of three pHs (5.0, 6.0 and 7.5) and two drug concentrations (8/3/6 and 1/1/1 mg/ml for 5-fluorouracil, oxaliplatin and calcium levofolinate, respectively) were examined. A high-performance liquid chromatography method was developed to separate and quantify the three drugs in one run. At higher concentrations, the ternary mixture was unstable regardless of pH. By reducing concentration, drug stability and compatibility in the mixture was improved at pH 5.0 for up to 3 days at +5°C ± 3 °C. In addition, binary mixtures provided stable properties at defined pHs. 5-fluorouracil/oxaliplatin mixture was stable at pH 5.0 over 48 hours while 5-fluorouracil/calcium levofolinate mixture was stable at pHs 6.0 and 7.5 up to 7 days. [ABSTRACT FROM AUTHOR]