Aggregate (Hoboken, N.J.)最新文献

Cartilage tissue engineering is a promising strategy to repair damaged tissue and reconstruct organ function, but the scaffold-free cartilage regeneration technology is currently limited in its ability to construct three-dimensional (3D) shapes, maintain the chondrogenic phenotype, and express cartilage-specific extracellular matrix (ECM). Recently, cartilaginous organoids (COs), multicellular aggregates with spheroid architecture, have shown great potential in miniaturized cartilage developmental models in vitro. However, high-efficiency and transferable in vivo organoid-based 3D cartilage regeneration technology for preclinical research needs further exploration. In this study, we develop novel cartilaginous organoids bioassembly (COBA) strategy to achieve scaffold-free 3D cartilage regeneration, which displays batch-to-batch efficiency, structural integration, and functional reconstruction. For underlying molecule mechanism, cellular adhesion proteins significantly regulate cell aggregation and cytoskeleton reorganization to form cartilaginous spheroids, and the hypoxic microenvironment created by high-density cell aggregates synergistically activates hypoxia-inducible factor-1α-mediated glycolytic metabolism reprogramming to maintain the chondrogenic phenotype and promote cartilage-specific ECM deposition. Furthermore, separated COs can integrate into a complete and continuous cartilage tissue through the COBA approach, and thus facilitate raising the nasal dorsa in goats after minimally invasive injection. This study thus demonstrates the promise of COBA technology to achieve scaffold-free 3D cartilage regeneration for organoid-based translational applications.

In this work, Yoon and co-workers developed a nanostructured supramolecular phototherapeutic agent based on Förster resonance energy transfer mechanism. Such nanostructured phototherapeutic agent can enable the visualization of a tumor with a photoacoustic signal-to-liver ratio as high as 11.9, and ultimately achieving a notable therapeutic effect in a preclinical model at a low dose through the photodynamic and photothermal synergistic therapy (e514).

A novel strategy for nanoparticle size enlargement is developed by constructing a pair of similar nanodrugs, referred to as “twins-like nanodrugs (TLNs)”. The TLNs synchronously transport in blood, coalesce inside tumor and achieve particle aggregation for ultrasound-triggerable penetrative drug delivery (e476).

Aggregation-induced emission (AIE) materials emitting near-infrared (NIR) light offer advantages like deep tissue penetration, minimal background interference, and negligible tissue damage. Consequently, NIR-AIE holds great promise in biomedical applications, including cell and living imaging, photothermal and photodynamic therapy, making it a prominent research focus (e505).

An anti-drug-resistant bacteria core-shell structure is designed, containing antibacterial zeolitic imidazolate framework-8 (ZIF-8) as the core and bactericidal benzalkonium chloride (BAC) templated rough-surface mesostructured silica nanocomposite (RMSN) as the shell. The resultant ZIF-8@RMSN nanocomposite exhibits sustained release of BAC and zinc ions, leading to enhanced antibacterial and biofilm elimination properties against drug-resistant bacterial. In addition, ZIF-8@RMSN modified antibacterial band-aid possesses excellent anti-drug-resistant bacterial infection properties both in vitro and in vivo (e523).

Hofmeister effect is a famous physical chemistry phenomenon that was reported a hundred years ago, which firstly refers to the action of certain salts to decrease the solubility of proteins while others increase. The Hofmeister effect on the luminescent properties of cationic organic fluorophore is still obscure, especially for their room temperature phosphorescence (RTP). Herein, hydrophilic groups (quaternization pyridine) were introduced into carbazole molecules to obtain a series of carbazole derivatives (named CZ-Py⁺) with different counter anions in the Hofmeister series. These carbazole derivatives displayed tunable fluorescent color from cyan to yellow in the solid state following the Hofmeister sequence and anti-Hofmeister behavior in an aqueous solution. Moreover, RTP material with tunable emission color and lifetime was achieved by doping CZ-Py⁺ with Hofmeister series anion in polymethyl methacrylate and polyvinyl alcohol, which displayed good performance in time getting information encryption and anti-counterfeiting.

Type I photosensitizers (PSs) with the ability to generate reactive oxygen species (ROS) containing superoxide anion and hydroxyl radical have promising application potential for treating hypoxia tumors, but the deep mechanism of type II ROS converts to the type I ROS in the PSs is still unclear, it is urgent to reveal influencing factors about inducing type I ROS generation. Herein, six PSs with aggregation-induced emission properties, which were fabricated with the same electronic acceptor but different electronic donors and “π-bridge”, have been successfully prepared to explore the influencing mechanism of generating superoxide anion and hydroxyl radical from organic PSs. Experimental results discovered two factors containing molecular structure and aggregated environment could decide the ROS efficiency and types of PSs. On the level of designing molecular structure, we discovered that “π-bridge” with a lower energy level of the lowest triplet state could be beneficial for triggering the production of superoxide anion, and electronic donor of triphenylamine was an important factor in producing hydroxyl radical than another donor of dimethylamine. On the level of designing aggregates of PS-based polymeric nanoparticles, bovine serum albumin could improve largely the generation efficiency of superoxide anion. Due to the satisfactory ROS efficiency and better biocompatibility, synthetic PSs showed excellent photodynamic therapy outcomes in vitro/vivo.

The regulation of emission color, emission efficiency, and asymmetry factor is of great significance for the real applications of circularly polarized luminescent (CPL) materials. Herein, we develop a modular synthetic strategy toward full-color-tunable CPL materials based on chiral macrocyclic aggregation-induced emission (AIE) luminogens via delicate molecular engineering. Modular synthesis of chiral AIEgens with different acceptor moieties has afforded a series of bright solid emitters with tunable emission colors. These chiral cyclic AIEgens have retained high solid-state emission quantum yield and displayed CPL emission from blue to red as nano-aggregates, in liquid crystal matrix and polymer film. The strong acceptor units in the red-emitting chiral AIEgens RBTPE-2CN and SBTPE-2CN have rendered them twisted intramolecular charge transfer properties and solvatochromic luminescence. And polymer matrix with different polarity further facilitates the tuning of CPL emission color from green to red emission. These results have paved a reliable approach toward constructing full-spectra solid-state CPL material.

Clusterization-triggered emissive (CTE) materials have attracted great attention in recent years. The regulation of the emission property of materials with CTE property through supramolecular interactions is an excellent strategy for the construction of smart fluorescent materials. In this work, we have prepared a regulatable supramolecular polymer network with CTE properties through pillararene-based host−guest interactions. The pillar[5]arene-grafted poly(methyl methacrylate) (PMMA) showed a classic CTE character. After adding Brooker's merocyanine-grafted polymer to the solution of the pillar[5]arene-containing PMMA, the supramolecular polymer network gel formed by the host−guest interactions between pillararene and Brooker's merocyanine guest. This supramolecular network showed brighter fluorescence than the pillar[5]arene-grafted PMMA in the solid state. In addition, the fluorescence emission of the supramolecular network can be further regulated by pH conditions. After adding an acid, the Brooker's merocyanine-containing guest polymer was protonated, and the supramolecular network changed to a protonated network through host−guest interactions between protonated Brooker's merocyanine guest and pillararene. Interestingly, the fluorescence was quenched when the supramolecular network turned into the protonated network. After adding a base, the protonated network can convert back to the original network, along with recovery of the fluorescence. Therefore, the regulation of the fluorescence of the supramolecular polymer materials with CTE was successfully realized by pillararene-based host−guest interactions. Furthermore, this tailorable fluorescent supramolecular polymer network system was applied as an information encryption material.