Carbon nitride reinforced chitosan/sodium alginate hydrogel as high-performance adsorbents for free hemoglobin removal in vitro and in vivo.

Removing free hemoglobin generated during extracorporeal circulation remains a challenge. Currently, there is no adsorbent with specificity and good biosafety for removing hemoglobin. In this study, a new chitosan/sodium alginate/carbon nitride (CS/SA/C3N4) hydrogel adsorbent was prepared by blending SA with C3N4 to drop into CS/CaCl2 solution. The physicochemical properties of CS/SA/C3N4 hydrogel were evaluated using some techniques, including scanning electron microscope, Zeta potential measurement, and thermogravimetric analysis. Hemoglobin adsorption in vitro, stability, hemocompatibility, cell compatibility, inflammatory reaction and blood extracorporeal circulation in vivo were also evaluated. The findings revealed that the CS/SA/C3N4-0.4 % hydrogel exhibited an impressive adsorption capacity of 142.35 mg/g for hemoglobin. The kinetic data of hemoglobin adsorption were well-described by pseudo second-order model, while the isothermal model data conformed to the Langmuir model. The hardness and modulus of CS/SA/C3N4-0.4 % was 11.7 KPa and 94.66 KPa respectively, which indicated robust resistance to breakage. CS/SA/C3N4 demonstrated excellent hemocompatibility, biocompatibility and anti-inflammatory properties. In addition, the results of in vivo rabbit extracorporeal blood circulation experiment demonstrated that CS/SA/C3N4 could adsorb free hemoglobin from blood while maintaining high biosafety standard. Consequently, CS/SA/C3N4 hydrogel emerges as a promising candidate for use as a hemoglobin adsorbent in extracorporeal blood circulation system.

A Transparent Additive-Free Fibrous Facial Mask for Skin Moisturizing.

Most sheet facial masks for skincare are made of nonwovens and loaded with liquid active ingredients, which are usually opaque and require additives for long-term preservation. Herein, a Transparent Additive-Free Fibrous (TAFF) facial mask is reported for skin moisturizing. The TAFF facial mask consists of a bilayer fibrous membrane. The inner layer is fabricated by electrospinning functional components of gelatin (GE) and hyaluronic acid (HA) into a solid fibrous membrane to get rid of additives, the outer layer is an ultrathin PA6 fibrous membrane that is highly transparent, especially after absorbing water. The results indicate that the GE-HA membrane can quickly absorb water and become a transparent hydrogel film. By employing the hydrophobic PA6 membrane as the outer layer, directional water transport is achieved, which enables TAFF facial mask with excellent skin moisturizing effect. The skin moisture content is up to 84% ± 7% after placing the TAFF facial mask on the skin for 10 min. In addition, the relative transparency of the TAFF facial mask on the skin reaches 97.0% ± 1.9% when ultrathin PA6 membrane is used as the outer layer. The design of the transparent additive-free facial mask may serve as a guideline for developing new functional facial masks.

Spiral grass inspired eco-friendly zein fibrous membrane for multi-efficient air purification.

Air pollution, one of the severest threats to public health, may lead to cardiovascular and respiratory illnesses. In order to cope with the deteriorating air pollutant, there is an increasing demand for filters with high purification efficiency, but it's tough to strike a balance between efficiency and resistance. Fabricating an eco-friendly fibrous filter which can capture both PM2.5 and gaseous chemical hazards with high efficiency but under ultra-low resistance is a long-term challenge. Herein, inspired by the interesting ribbon shape of spiral grass, a green and robust 3D nonwoven membrane with controllable hierarchical structure made of self-curved zein nanofibers modified by zeolitic imidazolate framework-8 (ZIF-8) via bi-solvent electrospinning and fumigation welding method was fabricated. The obtained ZIF-8 modified zein membranes showed extraordinary overall performance with high PM2.5 removal efficiency (99.04 %) at a low stress drop (54.87 Pa), first-rate formaldehyde removal efficiency (98.8 %) and excellent photocatalytic antibacterial. In addition, the relatively weak mechanical properties of zein fibrous membranes have been improved via solvent fumigation welding of the joint zein fibers. This study provides a green and convenient insight to the manufacturing of environmentally-friendly zein fibrous membranes with high filtration efficiency, low air resistance and high formaldehyde removal for sustainable air remediation.

Preparation and evaluation of stingray skin collagen/oyster osteoinductive composite scaffolds.

The regeneration of bone defects is a major challenge for clinical orthopaedics. Herein, we designed and prepared a new type of bioactive material, using stingray skin collagen and oyster shell powder (OSP) as raw materials. A stingray skin collagen/oyster osteoinductive composite scaffold (Col-OSP) was prepared for the first time by genipin cross-linking, pore-forming and freeze-drying methods. These scaffolds were characterized by ATR-FTIR, SEM, compression, swelling, cell proliferation, cell adhesion, alkaline phosphatase activity, alizarin red staining and RT-PCR etc. The Col-OSP scaffold had an interconnected three-dimensional porous structure, and the mechanical properties of the Col-OSP composite scaffold were enhanced compared with Col, combining with the appropriate swelling rate and degradation rate, the scaffold was more in line with the requirements of bone tissue engineering scaffolds. The Col-OSP scaffold was non-toxic, promoted the proliferation, adhesion, and differentiation of MC3T3-E1 cells, and stimulated the osteogenesis-related genes expressions of osteocalcin (OCN), collagen type I (COL-I) and RUNX2 of MC3T3-E1 cells.

In-situ formable dextran/chitosan-based hydrogels functionalized with collagen and EGF for diabetic wounds healing.

Delayed or non-healing skin wounds causing gangrene or even amputation, greatly threats diabetic patients lives. Herein, a bioactive, in-situ formable hydrogel based wound dressing was designed through simple Schiff base reaction. Oxidized dextran (OD) and carboxyethyl chitosan (CEC) were crosslinked together and applied as the main porous framework of hydrogel. To improve the mechanical strength and biocompatibility, collagen (Col) and EGF (Epidermal Growth Factor) were introduced into OD-CEC precursors: (1) after addition of only Col, the mechanical strength of hydrogels was improved by participating the functional -NH2 group of Col into the crosslinking process. Moreover, swelling ratio was as high as 750% on 3%OD-3%CEC-Col (water retention rate was 65 wt% after 7 days). (2) Once we introduced both Col and EGF into the OD-CEC hydrogel, the proliferation of mouse embryonic fibroblast (NIH 3T3) cells was promoted using 3%OD-3%CEC-Col/EGF, an accelerated wound healing was observed with 86% wound closure after only 14 operative days. Hematoxylin and eosin (H&E) staining and Masson staining indicated the synergy of Col and EGF might promote new tissue's formation, well collagen distributions and thus accelerate skin regeneration, presenting great potentials in wound healing of diabetic patients.

[Development of Thrombus Aspiration Catheter].

Coronary disease is one of the highest mortality diseases in the world,and interventional therapy has been the best treatment choice for its low risks,high efficiency,less wound and rapid recovery after the operation.Thrombus aspiration catheter is one of the most important equipment in the interventional therapy instrument of coronary disease.This paper is based on the demand of clinical and market,designed and manufactured aspirated catheter for the treatment of coronary thrombosis.Through the performance comparison of the material,confirmed the main material quality of thrombus aspiration catheter and its organization.We also made the appraisement for the function of the material and the main performance of the thrombus aspiration catheter.The experiment turned out that our catheter performance is stable and also with highly reliable,which is absolutely fit for the using requirements of the clinical.

Neural intrinsic functional connectivity associated with sensation seeking in heavy metal music and classical music lovers.

The aim of this study was to investigate the spontaneous neural activity and functional connectivity in heavy metal music lovers (HMML) and classical music lovers (CML) as well as the neural correlates of sensation seeking in two groups. Thrity-six HMML and 30 CML underwent resting-state functional MRI scans. Fractional amplitude of low-frequency fluctuations and seed-based resting-state functional connectivity (RSFC) were computed to explore regional activity and functional integration. A voxel-wise two-sample t-test was used to test the differences between the two groups and a whole-brain correlation analysis was carried out to explore RSFCs that were related to sensation seeking scores in HMML and CML separately. Compared with CML, HMML showed lower fractional amplitude of low-frequency fluctuations in the right gyrus rectus and lower RSFC between the right gyrus rectus and the right precuneus. Correlation results indicate that preferences for heavy metal music and classical music were associated with the relationship between RSFC and sensation seeking. These findings may suggest the neural correlates of sensation seeking were related to music preference (heavy metal music vs. classical music).