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quently increased biocompatibility.Silver nanoparticles (AgNPs) have been widely used for sterilization due to their broad-spectrum bactericidal properties. However, there exist the problems of premature releasing and accumulative toxicity when free AgNPs are applied. This study proposed a one-pot hydrothermal strategy to synthesize carbon spheres immobilized silver nanoparticles (AgNPs@CS). The synthesis involves with silver ammonia solution as Ag precursor, and corn stalk as green reducing agent and carbon precursor. [https://www.selleckchem.com/products/quinine-dihydrochloride.html selleck compound] Furthermore, AgNPs@CS was anchored by cellulose nanofibers (CNF) to obtain the antibacterial composite paper. The obtained CNF/AgNPs@CS paper exhibited superior antibacterial properties against E. coli and S. aureus. Notably, the accumulative release rate of AgNPs from AgNPs@CS was 10.2% in 9 days, while that from CNF/AgNPs@CS paper was only 6.7% due to the anchoring effect of both CS and CNF, which was low for avoiding the cumulative toxicity problem. In addition, the mechanical and barrier properties of CNF/AgNPs@CS paper were also improved by 29.4% (tensile index), 2.7% (tear index), 7.4% (burst index), 10% (folding endurance), 0.8% (water vapor transmission) and 9.4% (oxygen transmission rate), respectively. Therefore, the composite paper has potential application as a medical antibacterial material.The measurement of renal function by important clinical parameters such as (Crt) clearance and glomerular filtration rate often goes wrong vis-à-vis the Crt level in human body. Hence, development of an accurate detection system over a wide range of Crt concentration in both blood and urine is medically essential. In this study, a new non-enzymatic electrochemical probe, carbon dots doped tungstic anhydride embedded on graphene oxide nanopanels (CDs/WO3@GO) is reported for picomolar-level Crt detection in blood and urine with a wide linear range (0.2-112.0 nM). The sensor is economical, reproducible, stable and interferents-free. The properties of CDs/WO3@GO were studied using various analytical techniques. The proposed electrochemical Crt sensor could be used as a sustainable alternative for diagnostic use.In this study, carboxymethyl cellulose (CMC)-glycol chitosan (GC) hydrogel, a potential three-dimensional (3D) printing biomaterial ink for tissue engineering applications was synthesized using simple, biocompatible in situ-gelling Schiff's base reaction and ionic interactions. Different grades of hydrogels (C70G30, C50G50 and C30G70) were synthesized at physiological conditions. The oxidation of CMC and imine bond formation in the hydrogel were confirmed spectroscopically. Scanning electron microscopic images revealed the crosslinked interconnected pores in the cross-sectioned hydrogels (dried). Swelling (equilibrium 1 h), porosity (~75%), in vitro degradation (&gt;30 days) and thermal gravimetric analyses of the dried gels were studied. Initially, cytotoxicity assay was evaluated using mouse osteoblastic cells (MC3T3). These experiments revealed that CMC-GC gels formed stable hydrogel networks and were biocompatible. Particularly, C50G50 gels showed high printability (continuous extrusion) and post-printing stshow that the CMC-GC gels are promising bio-ink candidates for 3D printing and loading proteins or drugs for tissue engineering applications.Dense extracellular matrix (ECM) is a primary obstacle that restrains the permeation of therapeutic drugs in tumor tissues. Degrading ECM with bromelain (Br) to increase drug penetration is an attractive strategy to enhance antitumor effects. However, the poor stability in circulation and potential immunogenicity severely limit their applications. In this work, a novel pH-sensitive nanocarrier was prepared by crosslinking Br with an ortho ester-based crosslink agent, and Br still retained a certain ability to degrade ECM after crosslinking. The nanoparticles showed higher DOX release rate than non-sensitive nanoparticles, and DOX release amount reached to 86% at pH 5.5 within 120 h. In vivo experiments revealed that the pH-sensitive nanoparticles could be degraded in mildly acidic condition, and the released Br further promoted nanoparticles penetration in tumor parenchyma via in situ hydrolysis of ECM. Furthermore, Br itself could inhibit the proliferation of tumor cells at high concentration, and produce synergistic antitumor effects with DOX. Finally, tumor growth inhibition of these nanoparticles reached to 62.5%. Overall, the bromelain-based pH-sensitive nanoparticles can be potential drug carriers for efficient drug delivery and tumor treatment.In the present study, the effects of Zn-3Cu-xFe (x = 0, 0.2, 0.5 wt%) alloys on endothelial cells (EA.hy926) and smooth muscle cells (A7r5), the hemocompatibility and antibacterial properties were also evaluated. The cell viability of EA.hy926 cells and A7r5 cells decreased with the increasing of extract concentration. At the same Zn2+ concentration (over 6 ppm), the cell viability of EA.hy926 cells increased with the addition of Cu or Cu and Fe content, but no significant effect on A7r5 cells was observed. The hemolysis rate of Zn-3Cu-xFe alloys samples was about 1%, and there was no adversely affected on platelets adhering to the surface of the Zn alloys. As Fe content increases in the Zn-Cu-Fe alloys, the antibacterial lower concentrations against Staphylococcus aureus and Escherichia coli was improved due to the higher degradation rate and more Zn2+ and Cu2+ released. Our previous study already showed that the Zn-Cu-Fe alloy exhibited excellent mechanical properties and moderate degradation rate. Based on the above results, the in vitro biocompatibilities and antibacterial properties of Zn-3Cu alloy are significantly improved by the alloying of trace Fe, and the hemocompatibility is not adversely affected, which indicated that Zn-Cu-Fe alloy is a promising vascular stents candidate material.Calcium silicate (CS) is envisioned as a good substrate for bone tissue engineering applications because it can provide bioactive ions like Ca2+ and Si4+ to promote bone regeneration. Calcination temperature is a critical factor in determining the crystallinity of CS ceramic, which subsequently influences its degradation and ion release behaviors. To investigate the effect of calcination temperature on the capacity of CS in inducing bone regeneration, CS nanofibers were fabricated via electrospinning of precursor sol-gel and subsequent sintering at 800 °C, 1000 °C or 1200 °C. As the calcination temperature was increased, the obtained CS nanofibers displayed higher crystallinity and slower degradation rate. The CS nanofibers calcined at 800 °C (800 m) would like to cause high pH (&gt;9) in cell culture medium due to its rapid ion release rate, displaying adverse effect on cell viability. Among all the preparations, it was found the CS nanofibers calcined at 1000 °C (1000 m) demonstrated the strongest promotion effect on the osteogenic differentiation of bone marrow mesenchymal stromal cells.