Cartilage is a specialized connective tissue with limited self-regenerative ability, and current cartilage-related trauma treatments often fail to achieve consistent healing. Developing bioinks that closely mimic the native physical, mechanical, and biological microenvironment of cartilage is a critical challenge in tissue engineering. Here, we present a systematic study on the development of composite bioinks reinforced with nanofibrous polyelectrolyte complexes (PECs) derived from various categories of biopolymers: proteins (gelatin), mucopolysaccharides (chondroitin sulfate), and polysaccharides (alginate) in combination with chitosan. By integrating PECs of distinct biochemical origin into a BSA-alginate matrix, we demonstrate precise modulation of key bioink properties relevant for cartilage tissue engineering. Our findings reveal that incorporating PECs significantly enhances crosslinking density, in vitro stability, and mechanical strength (>120 kPa compressive modulus and >170 kPa tensile modulus). All of the bioinks exhibit excellent printability, shape fidelity, shear-thinning behavior, and cytocompatibility. Specifically, bioinks incorporated with gelatin-chitosan and chondroitin sulfate-chitosan PECs demonstrated proliferation of encapsulated primary chondrocytes and production of cartilage-specific glycosaminoglycans within the bioprinted constructs after 14 days of in vitro culture. This work highlights the pivotal role of tailored PEC compositions in tuning the physicochemical, mechanical, and biological performance of natural polymer-based bioinks. Our approach provides a versatile platform for engineering next-generation cartilage-biomimetic bioinks, offering significant promise for advancing cartilage tissue engineering.

Urothelial carcinoma of the bladder is one of the most common malignancies of the urinary tract. It remains a therapeutic challenge due to its high recurrence rate and resistance to conventional treatments. Photodynamic therapy (PDT) is an attractive, minimally invasive alternative that enables spatially controlled tumor ablation by activating photosensitizers (PS) with visible light, generating reactive oxygen species (ROS), mainly singlet oxygen (1O2), and inducing the targeted death of tumor cancer cells. However, due to poor aqueous solubility and aggregation of porphyrin-based PS, their clinical application is often limited. In this study, we report the biological evaluation of three thiopyridinium porphyrin-cyclodextrin conjugates (Por-CD 1a-3a) designed to enhance solubility and cellular delivery while preserving photodynamic activity. In the UM-UC-3 human bladder cancer cell line, we demonstrate that these conjugates exhibit distinct cellular uptake kinetics. PS 1a was rapidly internalized, reaching early saturation within 2 h; PS 2a displayed a gradual and sustained accumulation up to 4 h; and PS 3a demonstrated significant uptake within 30-60 min followed by stabilization. None of the compounds induced significant cytotoxicity in the absence of light at concentrations of 5 or 10 μM, confirming their dark safety profile. After light irradiation, PS 1a-3a produced strong PDT effect, with cytotoxicity profiles directly linked to their absorption properties. PS 1a showed rapid and stable phototoxicity, PS 2a exhibited a slower cytotoxic response, and PS 3a caused intense early phototoxicity even after short incubation periods. These findings indicate that Por-CD conjugates possess favorable cellular internalization and strong PDT efficacy. The three derivatives emerge as promising candidates for optimizing PDT strategies targeting bladder cancer cells.

Tung oil (TO) and its derivatives, characterized by a high content of α-eleostearic acid, exhibit significant potential as renewable feedstocks for the development of sustainable biopolymers, particularly for structural keratin repair applications. In this study, Tung free fatty acids (TF) were generated in a one-step process from TO via a vortex fluidic device (VFD)-assisted saponification process, enabling rapid, solvent-minimal conversion with high efficiency while preserving the reactive conjugated triene system. TO, TF, and a hybrid TO-TF (1:1) copolymer were then subsequently formed under natural solar irradiation. Morphological analysis revealed that the TO-TF copolymer yields a homogeneous, conformal film, attributed to the steric modulating effect of flexible TF chains, which regulates excessive crosslinking and mitigates the brittle network formation characteristic of neat TO polymers. Structural analysis confirmed a chemically saturated surface in the copolymer, suggesting enhanced resistance to oxidative degradation. Differential scanning calorimetry revealed that the copolymer exhibited a higher post-curing transition temperature (165 °C) compared to the TO polymer (142 °C) and TF polymer (134 °C), indicating enhanced thermal network stability. Rheological measurements demonstrated improved viscoelastic performance, with a strain yield approximately seven times greater than that of the TF polymer, confirming a superior balance between flexibility and mechanical resilience. When formulated as an emulsion and applied to bleached hair under thermal styling conditions, the TO-TF (1:1) emulsion treatment produced uniform surface coverage and effective cuticle sealing on the hair surface, leading to significant mechanical recovery. Notably, yield stress increased from 89 to 124 MPa, and Young's modulus improved by over 40% without compromising fiber elongation at break. These results demonstrated that copolymerizing TO with VFD-based TF yields a structurally optimized, sustainable biopolymer capable of reinforcing damaged hair. The established structure-performance relationship highlights its potential for next-generation eco-friendly hair-repair applications.

Triple-negative breast cancer (TNBC) poses a serious threat to the lives and health of patients, as traditional treatments are limited by psychological burden, systemic toxicity, or drug resistance. Photonic hyperthermia triggered by the second near-infrared (NIR-II) window is a promising minimally invasive strategy. Herein, we synthesized SnSe nanosheets via a simple, scalable method for NIR-II-triggered photonic tumor hyperthermia. SnSe nanosheets exhibited irregular lamellar structures with uniform Sn/Se distribution, favorable biocompatibility, and prominent photothermal performance under NIR-II irradiation. Under NIR-II irradiation, the SnSe+NIR-II group significantly suppressed tumor growth. This work offers a platform based on NIR-II light-induced photonic tumor hyperthermia, providing a minimally invasive strategy for TNBC treatment.

FeSe2/rGO nanohybrids were prepared via in situ one-pot synthesis using the hydrothermal method and were assessed for their potential for peroxidase-like activity. Structural and morphological analysis using FE-SEM and TEM confirmed the successful in situ growth and uniform distribution of FeSe2 NPs onto the rGO nanosheet matrix. Furthermore, the FeSe2/rGO nanohybrids showed superior and enhanced peroxidase-like activities compared to the bare FeSe2, as demonstrated using two substrates, 3,3',5,5'-tetramethylbenzidine (TMB) and o-phenylenediamine (OPD). Michaelis-Menten kinetics showed a significantly lower Km of 0.00952 mM for TMB and 7.62 mM for H2O2, along with a high Vmax of 6.48 × 10-8 M s-1 (TMB) and 1.706 × 10-6 Ms-1 (H2O2) for FeSe2/rGO, outperforming bare FeSe2 and several other reported nanozymes. The kinetic parameters showed a strong substrate affinity and improved catalytic efficiency. Mechanistic study using terephthalic acid (fluorescent probe) revealed that •OH is majorly responsible for substrate oxidation, which is significantly enhanced by the synergistic effect of FeSe2 and rGO. Furthermore, in support of our experimental results, molecular docking studies with multiple peroxidase proteins also showed significantly higher binding affinities for FeSe2/rGO (-9.9 to -11.9 kcal mol-1), as compared to FeSe2 (-4.8 to -9.1 kcal mol-1). Overall, this work highlights FeSe2/rGO as a robust peroxidase mimic and efficient nanozyme with strong potential for colorimetric sensing and catalytic performance.

Liposomes are valuable in drug and vaccine delivery. However, due to limited stability in the gastric environment, there is a need to optimize liposomes for oral delivery. This study demonstrates the potential of pectin-coated cationic liposomes for mucosal delivery. Low methoxylated (LM), low methoxylated amidated (LMA), or high methoxylated (HM) pectins were coated onto cationic adjuvant formulation (CAF04) liposomes. The resulting liposomes were characterized to determine their in vitro stability in a simulated intestinal medium, interactions with mucins, and diffusivity across artificial mucus. Subsequently, liposome retention after in situ intestinal perfusion in rats and liposome uptake after incubation with macrophage-like cells were determined. In vitro stability tests in simulated intestinal fluid revealed that the pectin coating protected the liposomes against premature degradation. Mucin interaction studies showed that LM and LMA-pectin coatings created a protective buffer, avoiding excessive complexation with mucin. Diffusivity of the liposomes across artificial mucus revealed that the diffusivity of particles across mucus was influenced by both steric obstructions and interactive barriers. In situ intestinal perfusion demonstrated that pectin-coated liposomes were retained in the intestine, and cellular uptake studies confirmed that the pectin coating did not inhibit the uptake of the liposomes by macrophages. Overall, pectins demonstrated potential as excipients for mucosal delivery systems. In the context of oral liposome-based vaccine formulations, they can mitigate undesirable interactions such as complexation with bile salts and mucins, while preserving the cellular uptake efficiency of the particles.

It is challenging to develop multiresponsive polypeptide theranostics that can respond to the tumor microenvironment (TME) for highly efficient chemodynamic therapy (CDT) while simultaneously alleviating tumor hypoxia. Inspired by protein biomineralization and utilizing zwitterionic phosphorylcholine-bearing polycysteine as a multivalent template, herein, a kind of MnOx/CaCO3-embedded polypeptide nanomodulator (PCMC) was easily constructed by a one-pot method. Upon the redox reaction of MnOx with intracellular glutathione (GSH), released Mn2+ mediated a Fenton-like reaction to transform endogenous H2O2 into cytotoxic ·OH, enabling GSH depletion-enhanced CDT, while MnOx also consumed H2O2 into O2 to relieve hypoxia. Meanwhile, the Ca2+ release from CaCO3 in the PCMC induced calcium overload to generate reactive oxygen species (ROS), synergizing with MnOx to boost CDT for killing 4T1 cells. The hypoxia staining assay and intracellular GSH and Ca2+ measurements corroborated that the PCMC effectively alleviated hypoxia and depleted intracellular GSH while inducing calcium overload in 4T1 cells. Remarkably, PCMC could accumulate in tumors, implement a T1-weighted magnetic resonance imaging (MRI) in 4T1 tumor-bearing mice, and achieve a synergistic CDT antitumor efficacy while heavily alleviating tumor hypoxia, as evidenced by means of H&E, TUNEL, ROS, and HIF-1α assays. Importantly, this work offers a versatile strategy for designing the TME-responsive polypeptide/metal ion hybrid nanoparticles to amplify CDT and alleviate hypoxia in tumors, opening an avenue for the MRI-guided drug/dye-free cancer theranostics.

Metallic plating systems composed of titanium and its alloys remain the standard treatment for craniofacial bony fixation but may require secondary removal due to infection, implant migration, or discomfort. Absorbable polymeric alternatives reduce those risks but lack sufficient strength for load-bearing applications. Thus, biodegradable metallic implants may eliminate complications and secondary procedures while maintaining the structural integrity. Our previous work demonstrated the fabrication of immiscible Fe-AZ31 composites via additive manufacturing with improved degradation kinetics over pure iron. This study aimed to evaluate the in vitro and in vivo biocompatibility of Fe-AZ31 composites for potential craniofacial fixation applications. Pure iron (Fe), magnesium (Al-Mg-Zn) alloy (AZ31), and Fe-AZ31 samples were fabricated for extract-based cytotoxicity testing using HFF-1 fibroblasts, L929 fibroblasts, and hFOB osteoblasts. Metal extracts were prepared at a 3 cm2/mL surface-to-volume ratio in complete media at 37 °C and cell viability was measured by live/dead assay after 24 and 72 h exposure. For in vivo evaluation, Fe-AZ31, Fe, and titanium (Ti) plates were implanted subcutaneously in wild type mice for 6 weeks and 3 and 6 months. Implant degradation, histologic response, hematology, and serum biochemistry were assessed. Fe-AZ31 extracts demonstrated ≥70% cell viability across all cell types at both time points with normal cell morphology and adhesion, whereas AZ31 extracts caused marked cytotoxicity associated with pronounced alkalization (pH 10.53). In vivo, Fe-AZ31 implants exhibited gradual surface corrosion accompanied by mild, transient inflammation and minimal capsule formation over time. No systemic toxicity was observed. Hematology and serum biochemistry remained within the physiological limits. Additively manufactured Fe-AZ31 composites demonstrate acceptable cytobiocompatibility and favorable tissue responses, supporting their development as bioresorbable metallic fixation devices for craniofacial reconstruction.

The rise of drug-resistant microbes has made antimicrobial therapy increasingly challenging, and despite several reports on peptide-functionalized silver nanoparticles, their efficacy against Mycobacterium species remains largely unexplored. In this study, we synthesized short peptide functionalized silver nanoparticles to develop an effective antimycobacterial agent, where peptides acted as both reducing and stabilizing agents for the one-pot synthesis of silver nanoparticles (AgNPs). The developed nanoparticles were characterized by high-resolution transmission electron microscopy (HR-TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), and UV-visible spectroscopy (UV-vis). The positively charged peptide-capped silver nanoparticles exhibited significant antimycobacterial activity against acid-fast mycobacterial strains, including Mycobacterium smegmatis, Mycobacterium bovis, and Mycobacterium marinum, compared to peptides alone, which could be due to the integrated effect of the peptide-functionalized AgNPs. Among the synthesized nanoparticles, linear peptide 2 (LP 2) functionalized AgNP exhibited the highest antimycobacterial efficacy against the Mycobacterium strains, with the lowest MIC (5 μM). AgNP LP 2 was found to be efficient to penetrate the mycobacterial cell wall, inducing membranolytic activity, triggering oxidative stress and degrading DNA, which led to the death of mycobacterial cells. Molecular docking and molecular dynamics (MD) simulations of the peptides with key enzyme FadD32 (MsmFadD32), Mycobacterium smegmatis, demonstrated strong interactions near the active site cleft, indicating potential inhibition of the mycolic acid biosynthesis pathway by the LP 2 peptide. This disruption likely challenges the organism's pathogenicity and supports the peptides' role in contributing to membranolytic activity. Additionally, AgNP LP 2 demonstrated the ability to inhibit biofilm formation and effectively disrupt preformed mycobacterial biofilms while exhibiting negligible cytotoxicity toward human embryonic kidney (HEK293) cells. In summary, our results suggest that newly developed AgNPs exhibit antimycobacterial activity without compromising the cell viability of normal cells, making them highly potent as prospective antimycobacterial agents.

Multifunctional silk fibroin (SF) nanofibrous membranes incorporating cuttlefish ink (CI) and vitamin B2 (VitB2) were developed via water-based electrospinning as bioactive scaffolds for soft tissue regeneration and laser-assisted tissue welding. CI provided antioxidant and photothermal properties, while VitB2 promoted cellular proliferation. Membranes exhibited controlled VitB2 release and CI retention within the matrix. NIH-3T3 fibroblast assays confirmed high viability (>80% at 48 h), with CI promoting adhesion and cytoskeletal organization, and VitB2 enabling formation of a confluent, organized cell layer. Laser-assisted welding produced satisfactory adhesion and shear-stress resistance on the order of ten kPa in ex vivo tendons, corneas, and sclerae, while keeping tissue temperatures below the 60 °C threshold for thermal damage. These findings highlight CI- and VitB2-loaded SF membranes as sustainable, cytocompatible scaffolds with antioxidant and adhesive functionalities, offering a versatile platform for soft tissue repair via an adhesive-free approach.