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POXylated polyurea dendrimer nanoparticles (PUREG4OOx48) are loaded with sildenafil (SDF) by a supercritical carbon dioxide–assisted (scCO2) impregnation. Further supercritical CO2‐assisted spray drying (SASD) leads to hybrid nano‐in‐micro dry powder formulations that are investigated aiming at efficient pulmonary delivery of SDF in pulmonary arterial hypertension treatment. This is the first report of the production of poly(D,L‐lactide‐co‐glycolide)‐cholesterol (PLGA‐Chol) microparticles processed by SASD. The optimized formulation of nano‐in‐microparticles is composed of PLGA, Chol, and PUREG4OOx48, loaded with SDF solutions in a 77:23 ratio (PLGA‐Chol:dendrimer, w/w). The dry powders are fully characterized and found to be highly biodegradable and biocompatible, and the SDF release profile evaluates under different pH values. The median mass average diameter (MMAD) of the nano‐in‐micro systems varies between 2.57 and 5 µm and the fine particle fraction (FPF) between 36% and 29% for PUREG4OMeOx48[PLGA‐Chol] and PUREG4OEtOx48[PLGA‐Chol], respectively. The data validate the potential use of these new formulations in inhalation therapy. In vitro studies are also carried out in order to evaluate the effect of the free drug in cell viability and formulations cytotoxicity. [ABSTRACT FROM AUTHOR]

POxylated polyurea dendrimer (PUREG4OOx48)‐based nanoparticles were loaded with paclitaxel (PTX) and doxorubicin (DOX) and micronized with chitosan (CHT) by using supercritical CO2‐assisted spray drying (SASD). Respirable, biocompatible, and biodegradable dry powder formulations (DPFs) were produced to effectively transport and deliver the chemotherapeutics with a controlled rate to the deep lung. In vitro studies performed with the use of the lung adenocarcinoma cell line showed that DOX@PUREG4OOx48 nanoparticles were much more cytotoxic than the free drug. Additionally, the DPFs did not show higher cytotoxicity than the respective nanoparticles, and DOX‐DPFs showed a higher chemotherapeutic effect than PTX formulations in adenocarcinoma cells. Inhalation chemotherapeutics: Micronized POxylated polyurea dendrimers loaded with anticancer agents (paclitaxel or doxorubicin) are fabricated by using green methodologies. These drug‐delivery systems reveal enhanced drug accumulation into neoplastic cells and allow a reduction in drug dosages and undesired side effects. [ABSTRACT FROM AUTHOR]

Pulmonary administration offers excellent advantages over conventional drug delivery routes, including increasing therapeutics bioavailability, and avoiding long-term safety issues. Formulations of nano-in-micro dry powders for lung delivery are engineered using (S)-ibuprofen as a model drug. These biodegradable formulations comprise nanoparticles of drug-loaded POxylated polyurea dendrimers coated with chitosan using supercritical-fluid-assisted spray drying. The formulations are characterized in terms of morphology, particle-size distribution, in vitro aerodynamic particle pulmonary distribution, and glutathione- S-transferase assay. It is demonstrated that ibuprofen-loaded nanoparticles can be successfully incorporated into microspheres with adequate aerodynamic properties, mass median aerodynamic diameter (1.86-3.83 μm), and fine particle fraction (28%-45%), for deposition into the deep lung. The (S)-ibuprofen dry powder formulations show enhanced solubility, high swelling behavior and a sustained drug release at physiologic pH. Also, POxylated polyureas decrease the (S)-ibuprofen toxic effect on cancer cellular growth. The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assays show no significant cytotoxicity on the metabolic activity of human lung adenocarcinoma ephithelial (A549) cell line for the lowest concentration (1 × 10−3 m), even for longer periods of contact with the cells (up to 120 h), and in the normal human dermal fibroblasts cell line the toxic effect is also reduced. [ABSTRACT FROM AUTHOR]

Hybrid photodiodes (HPD) systems are on the rise. The growing interest on these devices is mainly due to their power in image sensing and bioengineering solutions. In this work, a new class of donor‐acceptor dendrimers was synthesized and incorporated, along with a ruthenium sensitizer dye, into low cost devices comprised of one single layer of a biocompatible matrix (agarose). Exploring different electrodes, low current devices with a counter‐electrode dependent response have been successfully assembled at room temperature. Using a stainless steel electrode, sensitized donor‐acceptor dendrimers provide photodiode‐like systems having nA dark currents. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48635. [ABSTRACT FROM AUTHOR]

The Cover Feature shows engineered nano‐in‐microparticles specially designed for inhalation chemotherapy. The dry powder formulations, produced by supercritical CO2‐assisted co‐atomization of chitosan and polyurea dendrimers, deliver anticancer drugs to the deep lung. More information can be found in the Full Paper by R. B. Restani et al. on page 772 in Issue 10, 2018 (DOI: 10.1002/open.201800093). [ABSTRACT FROM AUTHOR]