This study reports the development of a polymeric carrierfor pulmonarysiRNA delivery via inhalation. Poly­(α,β-N-(2-hydroxyethyl)-d,l-asparamide) (PHEA) was first functionalized withdivinyl sulfone (DV) to form PHEA-VS, enabling controlled graftingof 1,2-bis­(3-aminopropylamino)­ethane (bAPAE, of about ∼25 mol%) and poly­(2-methyl-2-oxazoline) (PMeOx, of about ∼5 mol %).The resulting PHEA-VS-g-(PMeOx;bAPAE) copolymer containedprotonable amines for efficient siRNA complexation. Potentiometrictitration confirmed strong buffering capacity, while fluorescencestudies indicated pH-responsive membrane interaction, suggesting improvedendosomal escape. Polyplexes formed starting from a polymer/siRNAratio of 5, with diameters below 40 nm, showing stability in mucinsand pulmonary surfactant and protection against RNase degradation.Surface decoration with the cell-penetrating peptide penetratin (Pen)via a terminal alkyne on PMeOx enhanced cellular uptake and siRNArelease. Biocompatibility tests on 16-HBE cells showed viability over80% at high polymer concentrations. Functional assays in MDA-MB-231-LUCcells demonstrated effective gene silencing, particularly at a polymer/siRNAratio of 5. Combined with the favorable aerosolization propertiesof aqueous dispersions, these results highlight PHEA-VS-g-(PMeOx;bAPAE) as a versatile platform for pulmonary siRNA delivery,offering stability, biocompatibility, and targeted intracellular releasefor potential treatment of respiratory diseases.

Despite significant advances in nonlinear optical (NLO) materials, a systematic strategy for designing mid-infrared (mid-IR) NLO oxides that simultaneously exhibit strong second-harmonic generation (SHG) efficiency and wide optical transparency remains elusive. Herein, we report two polar antiperovskite oxide materials, (Pb1.5Cd1.5)GeO5 (PCGO) and Pb3GeO5 (PGO). Structural analyses reveal that PCGO adopts a 2H-hexagonal antiperovskite structure, whereas PGO features a three-dimensional antiperovskite framework. Both materials are thermally stable up to approximately 900 °C and exhibit wide optical transparency extending into the mid-IR region (0.3–13 μm). Powder SHG measurements indicate that PCGO and PGO exhibit strong SHG efficiencies of 0.5 and 1.3 times that of AgGaS2, respectively, along with particle-size-dependent SHG responses indicative of phase-matching behavior. Further first-principles calculations reveal moderate birefringence values of 0.053 and 0.058 at 1064 nm for PCGO and PGO, respectively, corresponding to shortest phase-matching (PM) wavelengths of 737 and 776 nm. A closer structural investigation and density functional theory calculations suggest that the pronounced distortions of OPb/Cd6 and OPb6 octahedra, together with highly polarizable cations, play a dominant role in governing the SHG responses. These results highlight polar antiperovskite oxides as a promising platform for the development of next-generation mid-IR NLO materials.

Hybrid adsorbents uniquely combine inorganic thermal stability with organic versatility. This study introduces a class of hybrid materials synthesized by cross-linking octa(vinyl)silsesquioxane (OV-SQ) with poly(2-phenyl-2-oxazoline) (PPhOx) using an AlCl3-mediated Friedel–Crafts reaction, demonstrating the application of this synthetic pathway to PPhOx. A key feature of this synthesis involves adjusting the stoichiometry to retain vinyl groups, facilitating postsynthetic modification via simple thiol–ene click chemistry. Consequently, nonfunctionalized adsorbents were successfully prepared alongside variants bearing alcohol, vicinal diol, and carboxyl functionalities. These resulting hybrids exhibited high surface areas and proved highly effective for adsorbing pesticides from aqueous environments. Detailed adsorption studies revealed that specific surface functionalities drastically influenced capacity; notably, the carboxyl-modified adsorbent displayed exceptional efficiency for removing 2-methyl-4-chlorophenoxyacetic acid (MCPA). Furthermore, these materials were integrated with ambient mass spectrometry (MS) to enable direct pesticide quantification. This combined analytical procedure significantly enhanced sensitivity, improving MCPA detection limits by a factor of 200 compared to standard solutions. This work establishes a versatile synthesis route using PPhOx and highlights the materials’ customizability. Ultimately, the integration of these hybrid adsorbents with ambient MS provides a rapid, efficient framework for screening environmental samples, offering a promising dual-function solution for detecting and removing hazardous contaminants.