Synthetic dyes are prone to water pollution during use, jeopardizing biodiversity and human health. This study aimed to investigate the adsorption and photocatalytic assist potential of sodium lignosulfonate (LS) in in situ reduced silver nanoparticles (AgNPs) and chitosan (CS)-loaded silver nanoparticles (CS-LS/AgNPs) as adsorbents for Rhodamine B (RhB). The AgNPs were synthesized by doping LS on the surface of chitosan for modification. Fourier transform infrared (FT-IR) spectrometry, energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to confirm the synthesis of nanomaterials. The adsorption and photocatalytic removal experiments of RhB were carried out under optimal conditions (initial dye concentration of 20 mg/L, adsorbent dosage of 0.02 g, time of 60 min, and UV power of 250 W), and the kinetics of dye degradation was also investigated, which showed that the removal rate of RhB by AgNPs photocatalysis can reach 55%. The results indicated that LS was highly effective as a reducing agent for the large-scale production of metal nanoparticles and can be used for dye decolorization. This work provides a new catalyst for the effective removal of dye from wastewater, and can achieve high-value applications of chitosan and lignin.

UNASSIGNED: Nanosilver-alginate dressing can effectively promote the healing of diabetic wounds in rats. However, due to the potential toxicity of nanosilver, its widespread application in hard-to-heal wound healing is limited. In the present study, the role and potential mechanism of nanosilver-free alginate gel (NSFAG) in the healing process of diabetic wounds were explored.
UNASSIGNED: A diabetic rat skin wound model was established, and wounds were treated with saline (NC group), nanosilver gel (NSG group) or nanosilver-free alginate gel (NSFAG group) for seven consecutive days.
UNASSIGNED: NSFAG significantly promoted wound healing and increased the content of protein and hydroxyproline in granulation tissues, and was superior to NSG (p<0.05). Immunohistochemical analyses revealed that the skin wound tissue structure of the NSFAG group was intact, and the number of skin appendages in the dermis layer was significantly higher compared with the NC group and the NSG group (p<0.05). Western blot analysis found that the protein expression of the epidermal stem cell marker molecules CK19 and CK14 as well the proliferation marker of keratinocytes Ki67 in the NSFAG group was significantly higher compared with the NC group or NSG group (p<0.05). Additionally, the proliferation marker of keratinocytes Ki67 in the NSFAG group was significantly higher compared with the NC or NSG group (p<0.05). Immunofluorescence staining analyses indicated that the CK19- and CK14-positive cells were mainly distributed around the epidermis and the newly formed appendages in the NSFAG group, and this result was not observed in the NC or NSG groups.
UNASSIGNED: The present findings demonstrate that NSFAG can effectively accelerate wound healing in diabetic rats by promoting epidermal stem cell proliferation and differentiation into skin cells, as well as formation of granulation tissue, suggesting that it can be a potential dressing for diabetic wounds.

Wound infection remains a major challenge for health professionals, because it delays wound healing and increases the overall cost and morbidity. Therefore, the development of new biomaterials with new antibacterial properties and healing effects remains a dire clinical need. To solve this problem, we developed silver nanoparticles embedded in γ-cyclodextrin metal-organic frameworks (Ag@MOF) and platelet-rich plasma (PRP)-loaded hydrogel systems based on methacrylated silk fibroin (SFMA) and methacrylate hyaluronic acid (HAMA) as Ag+ ion and growth factor delivery vehicles for inhibiting the growth of drug-resistant bacteria and promoting wound healing. The prepared SFMA/HAMA hydrogel demonstrated good rheological properties, swelling capability, appropriate mechanical properties and controllable biodegradability. The SFMA/HAMA/Ag@MOF/PRP hydrogel showed sustained release profiles of Ag+ ions and EGF. The SFMA/HAMA/Ag@MOF hydrogel have good inherent antibacterial properties against both gram-negative bacteria and gram-positive bacteria. The prepared hydrogel showed excellent cytocompatibility and could stimulate the growth and proliferation rate of NIH-3T3 cells. In vivo experiments showed that SFMA/HAMA/Ag@MOF/PRP hydrogel treatment enhanced the healing of full-thickness wounds, reduced inflammatory cell infiltration, and promoted re-epithelialization and collagen synthesis. All results indicated that the prepared hydrogel has tremendous potential to reduce wound infections and improve wound healing.

Copper (Cu) nanoparticles are considered a promising alternative to silver (Ag) and gold (Au) for printed electronics applications. Because Cu has higher electrical conductivity, it is significantly cheaper than Ag and Au. To study the applicability of electronic printing, we prepared Ag@Cu conductive ink by using a stepwise feeding method to disperse nano Ag and nano Cu in ethanol and water. The ink has the advantages of nontoxic, low content, and low cost. A three-dimensional (3D) model was designed, and a conductive pattern was printed on the photo paper substrate using extrusion 3D printing technology. The influence of waterborne resin on the adhesion of conductive patterns is discussed. The printed conductive pattern can maintain the stability of conductivity after 100 bending cycles. The conductive pattern has good thermal stability. It can be tested 10 times under 2 conditions of 85°C and room temperature to maintain good conductivity. This shows that Ag@Cu conductive ink printed flexible electronic products are competitive.

Foreign body reactions induced by macrophages often cause delay or failure of wound healing in the application of tissue engineering scaffolds. This study explores the application of nanosilver (NAg) to reduce foreign body reactions during scaffold transplantation. An NAg hybrid collagen-chitosan scaffold (NAg-CCS) was prepared using the freeze-drying method. The NAg-CCS was implanted on the back of rats to evaluate the effects on foreign body reactions. Skin tissue samples were collected for histological and immunological evaluation at variable intervals. Miniature pigs were used to assess the effects of NAg on skin wound healing. The wounds were photographed, and tissue samples were collected for molecular biological analysis at different time points post-transplantation. NAg-CCS has a porous structure and the results showed that it could release NAg constantly for two weeks. The NAg-CCS group rarely developed a foreign body reaction, while the blank-CCS group showed granulomas or necrosis in the subcutaneous grafting experiment. Both matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinase-1 (TIMP-1) were reduced significantly in the NAg-CCS group. The NAg-CCS group had higher interleukin (IL)-10 and lower IL-6 than the blank CCS group. In the wound healing study, M1 macrophage activation and inflammatory-related proteins (inducible nitric oxide synthase (iNOS), IL-6, and interferon-‍γ (IFN-‍γ)) were inhibited by NAg. In contrast, M2 macrophage activation and proinflammatory proteins (arginase-1, major histocompatibility complex-II (MHC-II), and found in inflammatory zone-1 (FIZZ-1)) were promoted, and this was responsible for suppressing the foreign body responses and accelerating wound healing. In conclusion, dermal scaffolds containing NAg suppressed the foreign body reaction by regulating macrophages and the expression of inflammatory cytokines, thereby promoting wound healing.
在组织工程支架的应用中，巨噬细胞引起的异物反应常导致伤口愈合延迟或失败。本研究探讨了纳米银（NAg）在支架移植过程中减少异物反应的作用。首先采用冷冻干燥法制备了包覆NAg的胶原-壳聚糖支架（NAg-CCS）。将Nag-CCS植入大鼠背部以评估对异物反应的影响，并在不同的时间间隔收集皮肤组织样本用于组织学和免疫学评估。小型猪创面愈合模型被用来评估NAg对皮肤伤口愈合的影响。在不同时间点对创面进行拍照，并收集组织样本用于移植后不同时间点的分子生物学分析。结果表明，NAg-CCS具有多孔结构，可以持续释放NAg超过2周。NAg-CCS组很少发生异物反应，而空白CCS组在皮下移植实验中出现明显的肉芽肿或坏死。NAg-CCS组的基质金属蛋白酶-1（MMP-1）和组织金属蛋白酶抑制剂-1（TIMP-1）均显着降低。Nag-CCS组比空白CCS组具有更高的白细胞介素（IL）‍-10和更低的IL-6。在创面愈合实验中，NAg显著抑制了M1巨噬细胞的活化和炎症相关蛋白（一氧化氮合成酶（iNOS）、IL-6和干扰素-γ（IFN-γ））的表达，而促进了M2巨噬细胞的活化和抗炎相关蛋白（精氨酸酶-1、主要组织相容性复合体-Ⅱ（MHC-Ⅱ）和抵抗素样分子-1（FIZZ-1））的表达，这些改变均有助于抑制创面的异物反应并加速创面的愈合。总之，含有NAg的真皮支架通过调节巨噬细胞极化和炎性细胞因子的表达来抑制异物反应，从而促进皮肤创面的修复。.

Our current knowledge on nanomaterials is mostly built on data from basic studies, and the application and developmental potentials of nanomaterials are emphasized. On the other hand, standard evaluation methods, models, exposure methods, standards, and guidelines for biological effect evaluation are inadequate. In response to the bottlenecks of supervision, scientific research institutes and regulatory organizations in China have cooperated closely to research and establish an evaluation system for nanomedical devices, and silver-containing nanomaterials have been adopted as an example. In such a context, reference materials, characterization strategies, in vitro and in vivo distribution and toxicity evaluation standards have been established. This article highlights research on the risk assessment of nanomedical device products (taking silver-containing nanomedical device products as an example) in China, including the characterization and release determination strategies, determination of nanosilver in tissues, applications of three-dimensional skin models and in vitro and toxicity evaluation standards have been established. This article highlights research on technical standards. As a consequence, the \"Guidelines for the safety and effectiveness evaluation of nanomedical devices\" were published in 2021, and a market entry framework for nanomedical devices has been preliminarily formed as a significant component in scientific supervision. This Guideline supervises the review and supervision of nanomedical devices and, therefore, provides a guarantee for the market access of nanomedical devices in China. This article is categorized under: Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials Toxicology and Regulatory Issues in Nanomedicine > Regulatory and Policy Issues in Nanomedicine.

Microbiological protection textile materials played an important role in the battle against the epidemic. However, the traditional active antimicrobial treatment of textiles suffers from narrow textile applicability, low chemical stability, and poor washability. Here, a high-strength adhesive nanosilver glue was synthesized by introducing nontoxic water-soluble polyurethane glue as a protectant. The as-prepared nanosilver glue could adhere firmly to the fiber surfaces by forming a flexible polymer film and could encapsulate nanosilver inside the glue. The as-prepared nanosilver had a torispherical structure with diameter of ~22 nm, zeta potential of -42.7 mV, and good dispersibility in water, and it could be stored for one year. Further studies indicated that the nanosilver glue had wide applicability to the main fabric species, such as cotton and polyester fabric, surgical mask, latex paint, and wood paint. The antimicrobial cotton and polyester fabrics were prepared by a simple impregnation-padding-baking process. The corresponding antimicrobial activity was positively correlated with nanosilver content. The treated fabrics (500 mg/kg) exhibited ultrahigh washing resistance (maintained over 99% antibacterial rates for 100 times of standard washing) and wear resistance (99% antibacterial rates for 8000 times of standard wearing), equivalent breathability to untreated fabric, improved mechanical properties, and good flexibility, demonstrating a potential in cleanable and reusable microbiological protection textiles.

Silver nanoparticles (AgNPs) were widely used in the antibacterial field because of their excellent antibacterial properties. In this study, we used hesperidin and pectin as reductants and stabilizers, and prepared uniform and stable Hesperidin-Pectin AgNPs (HP-AgNPs) by a simple microwave-assisted process. Increasing the proportion of hesperidin, P-AgNPs, HP-AgNPs1, HP-AgNPs2 and H-AgNPs were obtained respectively. With the increase of hesperidin ratio, the mean particle size and zeta potential increased gradually. Fourier transform infrared spectroscopy (FTIR) analysis showed that Ag+ was reduced by hesperidin and pectin. Antibacterial tests showed that HP-AgNPs2 showed the MIC values of 66.7 μg/mL against E. coli. In addition, HP-AgNPs2 was selected to clarify its antibacterial mechanism against E. coli. Morphological experiments showed that HP-AgNPs2 stress caused damage to the cell wall of E. coli, as well as leakage of its contents and an increase in reactive oxygen species (ROS). On the other hand, the release of Ag+ during cell co-culture was studied and the results showed that most of the Ag+ released was taken up by E. coli. The synergistic effect of hesperidin and pectin resulted in a significant enhancement of the antibacterial properties of AgNPs. These preliminary data suggest that HP-AgNPs has good antibacterial activity and may be developed as an effective antibacterial nanomaterial.

Nanosilver is a metallic silver monomer with a diameter of <100 nm, which has excellent antibacterial activity and is widely used in the fields of medicine and sanitation, disinfection of drinking water in daily life and feed additives in livestock and poultry farming. Heterophil extracellular traps (HETs) are an important part of innate immunity in chickens and have an excellent antimicrobial effect, but their excessive release caused tissue damage. Nanosilver overdose caused toxic effects in chickens, while immunotoxic effects of nanosilver on chickens have not been reported. In this study, we explored the effects of nanosilver-induced HETs on chicken liver and kidney damage and further investigated the molecular mechanism of nanosilver-induced HETs release. The results showed that nanosilver significantly upregulated serum HETs and caused liver and kidney damage. The classical structure of nanosilver-induced HETs was also observed, and nanosilver-induced HETs were dependent on reactive oxygen species (ROS), extracellular regulatory protein kinase (ERK)1/2, p38 and glycolysis pathways. In summary, this research suggests that nanosilver induced HETs release, but excessive HETs release also caused damage to chicken. It also helps to understand the importance of moderate application of nanosilver, which may improve animal immunity but avoid negative effects in safeguarding the economic efficiency of poultry farming.

In this study, we used the polysaccharide ulvan from the green macroalgae Ulva fenestrata to prepare the hydrogel for chronic diabetic wound healing. A natural polysaccharide-based hydrogel matrix (UC-DPA-Ag hydrogel) was prepared using ulvan dialdehyde, chitosan, dopamine (DPA) and silver nanoparticles (Ag NPs). Human umbilical cord mesenchymal stem cell lyophilized powder (hUC-MSCs) was loaded into the hydrogel to develop a novel chronic diabetic wound healing material (UC-DPA-Ag@hUC-MSCs). The resulting hydrogel features adequate mechanical properties, swelling capability, adhesiveness, antioxidant, antibacterial ability, and promoting cell proliferation and migration. In vivo wound healing in type II diabetic mellitus mouse wound model showed that hUC-MSCs loaded UC-DPA-Ag hydrogel could accelerate wound healing effectively. This advanced hydrogel provides a facile and effective way for diabetic chronic wound management. Furthermore, it offers a new route for the utilizing Ulva as a valuable biomaterial for the global and large-scale production of valued added biomaterials.