ACS Applied Bio Materials最新文献

Excess accumulation of misfolded and mutated human lysozyme (HuL) is the pathological hallmark of non-neuropathic systemic amyloidosis. These deposits are rich in cross β-sheet conformers and often exist as polymorphic fibrillar structures, which makes it a tricky and challenging task to design therapeutic interventions toward HuL-linked amyloidopathy. Here we aimed to design an effective antiamyloid metal nanoparticle formulation to target the exposed hydrophobic and aggregation-prone stretches in HuL. Initially, we synthesized and characterized piperine-coated gold nanoparticles (AuNPs^Pip). ThT-probed aggregation studies of HuL in the presence and absence of AuNPs^Pip revealed an inhibition of lysozyme aggregation. This inhibition effect was confirmed through dynamic light scattering (DLS) and fluorescence microscopy analyses. We further investigated whether AuNPs^Pip could bind to preformed fibrils and prevent the secondary nucleation process, which is a crucial step in amyloidogenesis. Our results showed that AuNPs^Pip not only prevented seed-induced aggregation but also disassembled preformed amyloid aggregates, which was not observed with AuNPs or piperine. Experimental and computational studies suggest that the retention of the lysozyme native structure and the ability of AuNPs^Pip to interact with the aggregation-prone residues are key factors in the inhibition mechanism. The findings of this work may aid in developing nanoparticle-based formulations to prevent pathologies linked to lysozyme aggregation.

This study explores cell death through photodynamic therapy (PDT) with β-cyclodextrin-encapsulated platinum(II)-based nanoparticles (Pt-NPs) and the effect on the NF-κB and stress pathways in glioblastoma. The encapsulation of the cyclometalated Pt(II) complex Pt(LL') within β-cyclodextrin (β-CD) enhances its biocompatibility, improves cellular penetration, and boosts emission, thereby increasing the effectiveness of PDT. Both Pt(LL') and Pt-NPs show minimal toxicity in the dark; however, Pt-NPs significantly increase toxicity toward glioblastoma Kr158 cells upon irradiation at 390 nm. The PDT-induced cell death is further validated through apoptosis assays and the modulation of some key survival pathways like NF-κB/p65, DJ-1, and ERp29. This is the first report of β-cyclodextrin-encapsulated platinum(II)-based nanoparticles designed to target glioblastoma cells through PDT, offering a promising strategy for enhancing therapeutic efficacy.

Messenger RNA (mRNA) has proven to be an effective vaccine agent against unexpected pandemics, offering the advantage of rapidly producing customized therapeutics targeting specific pathogens. However, undesired byproducts, such as double-stranded RNA (dsRNA), generated during in vitro transcription (IVT) reactions may impede translation efficiency and trigger inflammatory cytokines in cells after mRNA uptake. In this study, we developed a facile method using PEGylated polystyrene resins that were further surface-modified with graphene oxide (GO@PEG–PS) for the removal of dsRNA from IVT mRNA. The GO@PEG–PS resin adsorbed mRNA due to the property of graphene oxide (GO), which preferentially adsorbs single-stranded nucleic acids over double-stranded nucleic acids in the presence of Mg²⁺. The resin-bound single-stranded (ss) RNA was readily desorbed with a mixture of EDTA and urea, possibly by chelating Mg²⁺ and disrupting hydrogen bonding, respectively. Spin-column chromatography with GO@PEG–PS for IVT mRNA eliminated at least 80% of dsRNA, recovering approximately 85% of mRNA. Furthermore, this procedure precluded the salt precipitation step after the IVT reaction, which fractionates mRNAs from the IVT components, including nucleotides and enzymes. The purified mRNA exhibited enhanced protein translation with reduced secretion of interferon (IFN)-β upon mRNA transfection. We anticipate that the mRNA purification chromatography system employing GO@PEG–PS resin will facilitate the removal of dsRNA contamination during mRNA production.

Messenger RNA (mRNA) has proven to be an effective vaccine agent against unexpected pandemics, offering the advantage of rapidly producing customized therapeutics targeting specific pathogens. However, undesired byproducts, such as double-stranded RNA (dsRNA), generated during in vitro transcription (IVT) reactions may impede translation efficiency and trigger inflammatory cytokines in cells after mRNA uptake. In this study, we developed a facile method using PEGylated polystyrene resins that were further surface-modified with graphene oxide (GO@PEG-PS) for the removal of dsRNA from IVT mRNA. The GO@PEG-PS resin adsorbed mRNA due to the property of graphene oxide (GO), which preferentially adsorbs single-stranded nucleic acids over double-stranded nucleic acids in the presence of Mg²⁺. The resin-bound single-stranded (ss) RNA was readily desorbed with a mixture of EDTA and urea, possibly by chelating Mg²⁺ and disrupting hydrogen bonding, respectively. Spin-column chromatography with GO@PEG-PS for IVT mRNA eliminated at least 80% of dsRNA, recovering approximately 85% of mRNA. Furthermore, this procedure precluded the salt precipitation step after the IVT reaction, which fractionates mRNAs from the IVT components, including nucleotides and enzymes. The purified mRNA exhibited enhanced protein translation with reduced secretion of interferon (IFN)-β upon mRNA transfection. We anticipate that the mRNA purification chromatography system employing GO@PEG-PS resin will facilitate the removal of dsRNA contamination during mRNA production.

Excess accumulation of misfolded and mutated human lysozyme (HuL) is the pathological hallmark of non-neuropathic systemic amyloidosis. These deposits are rich in cross β-sheet conformers and often exist as polymorphic fibrillar structures, which makes it a tricky and challenging task to design therapeutic interventions toward HuL-linked amyloidopathy. Here we aimed to design an effective antiamyloid metal nanoparticle formulation to target the exposed hydrophobic and aggregation-prone stretches in HuL. Initially, we synthesized and characterized piperine-coated gold nanoparticles (AuNPs^Pip). ThT-probed aggregation studies of HuL in the presence and absence of AuNPs^Pip revealed an inhibition of lysozyme aggregation. This inhibition effect was confirmed through dynamic light scattering (DLS) and fluorescence microscopy analyses. We further investigated whether AuNPs^Pip could bind to preformed fibrils and prevent the secondary nucleation process, which is a crucial step in amyloidogenesis. Our results showed that AuNPs^Pip not only prevented seed-induced aggregation but also disassembled preformed amyloid aggregates, which was not observed with AuNPs or piperine. Experimental and computational studies suggest that the retention of the lysozyme native structure and the ability of AuNPs^Pip to interact with the aggregation-prone residues are key factors in the inhibition mechanism. The findings of this work may aid in developing nanoparticle-based formulations to prevent pathologies linked to lysozyme aggregation.

This study explores cell death through photodynamic therapy (PDT) with β-cyclodextrin-encapsulated platinum(II)-based nanoparticles (Pt-NPs) and the effect on the NF-κB and stress pathways in glioblastoma. The encapsulation of the cyclometalated Pt(II) complex Pt(LL′) within β-cyclodextrin (β-CD) enhances its biocompatibility, improves cellular penetration, and boosts emission, thereby increasing the effectiveness of PDT. Both Pt(LL′) and Pt-NPs show minimal toxicity in the dark; however, Pt-NPs significantly increase toxicity toward glioblastoma Kr158 cells upon irradiation at 390 nm. The PDT-induced cell death is further validated through apoptosis assays and the modulation of some key survival pathways like NF-κB/p65, DJ-1, and ERp29. This is the first report of β-cyclodextrin-encapsulated platinum(II)-based nanoparticles designed to target glioblastoma cells through PDT, offering a promising strategy for enhancing therapeutic efficacy.

Polymer nanobiocomposites (PNCs) prepared with graphitic carbon nitride (GCN) nanosheets in polybutylene adipate terephthalate (PBAT)/polylactic acid (PLA) bioblends were processed using a three-step processing technique that involved: (1) a solution-based GCN exfoliation step; (2) a masterbatching step of GCN in PBAT by solution processing; and (3) a melt-compounding step where the masterbatch was mixed with pristine PLA to delaminate the 2D GCN layers by extrusion high-shear mixing and to deposit them onto the biphasic PLA/PBAT morphology. Due to the partial exfoliation of GCN, this process led to a concurrent presence of three distinct morphologies within the PNCs’ microstructure: (1) Type 1, characterized by an unaltered interface and PLA matrix, with minimal GCN deposition within the PBAT phase; (2) Type 2, distinguished by a diffused and stiff interface with GCN distribution in both the dispersed (PBAT) and matrix (PLA) phases; and (3) Type 3, featuring unmodified interfaces and GCN localization across both PLA and PBAT phases with a stair-like morphological texture. Such a morphological combination generates distinct crack propagation micromechanics, thereby influencing the variability of the plastic deformational behavior of their PNCs. Particularly, the Type 1 morphology enables GCN to act as a secondary stress-dissipating agent, whereas the PBAT domains serve as the primary stress-absorbing sites, contributing to enhanced crack propagation energy requirements. Contrarily, Type 3 (slightly) and Type 2 (predominantly) morphologies invert GCN’s role from stress dissipation to stress concentration due to its localization within the PLA matrix. Differential scanning calorimetry revealed a crystallinity increase in the PNCs until 0.1 wt % GCN, followed by a decline, likely due to agglomeration at higher contents. Thermogravimetric analysis showed that GCN addition improved the thermostability of the bioblends, attributed to the GCN’s nanophysical and pyrolytic barrier effect. Moreover, using both direct and indirect methods, GCN did not impair the biocompatibility of the bioblends as confirmed via cytocompatibility assays.

This study investigates the use of bimetallic copper-silver nanoclusters (Cu-AgNCs) for fluorescence turn-on sensing of leucine, a potential biomarker for cancer detection. These nanoclusters exhibit high fluorescence tunability and specificity, with Fe³⁺ serving as a quencher to facilitate leucine detection. The fluorescence recovery mechanism is attributed to the interaction of leucine with Fe³⁺, alleviating the quenching effect on the metal nanoclusters. This bimetallic nanocluster is a promising platform for biomarker identification in cancer diagnosis. The fluorescence enhancement upon leucine binding provides a measurable signal, confirming the feasibility of these nanoclusters as noninvasive sensors for cancer biomarkers. The sensor achieves a detection limit of 0.58 μM and demonstrates a linear response within the range of 110-657 μM. This approach offers a promising method for noninvasive cancer diagnostics using saliva and urine samples. Additionally, the method's reproducibility and robustness further support its potential in clinical applications, providing a cost-effective and accessible technique for early cancer detection.

This study investigates the use of bimetallic copper–silver nanoclusters (Cu-AgNCs) for fluorescence turn-on sensing of leucine, a potential biomarker for cancer detection. These nanoclusters exhibit high fluorescence tunability and specificity, with Fe³⁺ serving as a quencher to facilitate leucine detection. The fluorescence recovery mechanism is attributed to the interaction of leucine with Fe³⁺, alleviating the quenching effect on the metal nanoclusters. This bimetallic nanocluster is a promising platform for biomarker identification in cancer diagnosis. The fluorescence enhancement upon leucine binding provides a measurable signal, confirming the feasibility of these nanoclusters as noninvasive sensors for cancer biomarkers. The sensor achieves a detection limit of 0.58 μM and demonstrates a linear response within the range of 110–657 μM. This approach offers a promising method for noninvasive cancer diagnostics using saliva and urine samples. Additionally, the method’s reproducibility and robustness further support its potential in clinical applications, providing a cost-effective and accessible technique for early cancer detection.

Engineering thick skin tissue substitutes resembling the physiochemical and mechanical properties of native tissue is a significant challenge. Melt electrowriting (MEW) is a powerful technique with the capability of fabricating highly ordered structures with fine fiber diameters, closely replicating the native extracellular matrix (ECM). In this study, we constructed melt electrowritten porous polycaprolactone (PCL) scaffolds with three different geometries by depositing fibers at 0–90 and 60–120° in a mesh structure and in a honeycomb-like orientation to assess the effects of the microstructure on the mechanical strength of the scaffold and cellular behavior. These scaffolds were subsequently infilled with gelatin hydrogel, encapsulating human skin dermal fibroblasts (HSFs) and human umbilical vein endothelial cells (HUVECs). Mechanical tensile tests revealed that the honeycomb microstructure of the hybrid PCL/gelatin scaffold exhibited greater elongation at failure, along with an acceptable elastic modulus suitable for skin tissue applications. All scaffolds provided a cytocompatible microenvironment that maintained over 90% cell viability and preserved typical cell morphology. HSFs were guided through the PCL fibers to the apical surface, while HUVECs were distributed within the gelatin hydrogel within the hybrid structure. Additionally, HSFs’ alignment was regulated by the scaffold geometry. Notably, the expression of CD31 in HUVECs─a key transmembrane protein for capillary formation─increased significantly over a 14 day incubation period. Among those, 0–90° mesh and honeycomb geometries showed the greatest effects on the upregulation of CD31. These findings demonstrate that the microstructural guidance of HSFs and their interaction with HUVECs in hybrid structures play a crucial role in promoting vascularization. In conclusion, the honeycomb MEW-gelatin hybrid scaffold demonstrates significant potential for effectively replicating both the mechanical and physicochemical properties essential for full-thickness skin tissue substitutes.