Abstract The covalent functionalization of graphene oxide (GO) with chitosan (CS) is successfully accomplished via a facile amidation process. CS‐grafted GO (GO–CS) sheets consist about 64 wt.% CS, which imparts them good aqueous solubility and biocompatibility. Additionally, the physicochemical properties GO–CS are studied. As novel nanocarrier, applied to load water‐insoluble anticancer drug, camptothecin (CPT), π–π stacking hydrophobic interactions. It demonstrated that possesses superior...

Abstract Covalently functionalized graphene sheets are prepared by grafting a well‐defined thermo‐responsive poly( N ‐isopropylacrylamide) (PNIPAM) via click chemistry. The PNIPAM‐grafted (PNIPAM‐GS) consist of about 50% polymer, which endows the with good solubility and stability in physiological solutions. PNIPAM‐GS exhibits hydrophilic to hydrophobic phase transition at 33 °C, is relatively lower than that PNIPAM homopolymer because interaction between grafted PNIPAM. Moreover, through...

On the basis of thermoreversible sol-gel transition behavior κ-carrageenan in water, a double-network (DN) hydrogel has been fabricated by combining an ionically cross-linked network with covalently polyacrylamide (PAAm) network. The κ-carrageenan/PAAm DN demonstrated excellent recoverability and significant self-healing capability (even when notched). More importantly, warm pregel solution κ-carrageenan/AAm can be used as ink three-dimensional (3D) printer to print complex 3D structures...

Carbon nanomaterials such as multiwalled carbon nanotubes (MWCNTs) and graphene oxide (GO) have been functionalized by highly hydrophilic biocompatible poly(vinyl alcohol) (PVA) for loading delivery of an anticancer drug, camptothecin (CPT). For the first time, CPT was loaded onto MWCNT–PVA GO–PVA through π–π interactions its capability to kill human breast skin cancer cells investigated.

Three dimensional (3D) bioprinting technologies with appropriate bioinks are potentially able to fabricate artificial tissues or organs precise control. A bioink is a mixture of biomaterial and living cells, which for bioprinting. Hydrogels the most appealing candidates biomaterials because they have many similar features natural extracellular matrix could also provide highly hydrated environment cell proliferation. In this field bio-fabrication, particularly in bioprinting, lack suitable...

A robust alginate/methylcellulose (Alg/MC) blend hydrogel, with a strategy to improve adhesion between printed layers, has been fabricated for the first time three-dimensional (3D) bioprinting. The optimized Alg/MC hydrogel exhibits highly thixotropic property, great extrudability, and stackability. With treatment by trisodium citrate (TSC) solution, interfacial bonding layers is significantly improved. TSC solution acts as chelating agent remove superficial calcium ions at each layer....

In recent years, hydrogels have been used as important biomaterials for 3D printing of three dimensional tissues or organs. The key issue a successful scaffold is the selection material with good printability. Rheological properties are believed to pay an role in However relations between rheological and printability not extensively studied. this study, alginate-based were prepared model extrusion-based printer graphene oxide was added modify hydrogels. studies performed hydrogel samples...

Thermal gelation was studied for aqueous gelling solutions of a methylcellulose. An attempt made to elucidate the gel network structure and validity scaling laws. observed on heating, it reverted liquid state cooling. The thermoreversibility heating/cooling rate dependent process. For isothermally stabilized samples, 42.5 °C found be critical temperature differentiating weak gels from strong gels. Below °C, elasticity evolved by following law with as Ge ∼ [(T − Tc)/Tc]2.93 where is...

Aqueous solutions of a methylcellulose, ranging from 0.30 to 2.49 wt %, were studied by means micro differential scanning calorimetry (micro DSC) and rheology. The effects polymer concentration on the thermodynamic properties these examined through heating process following cooling at fixed rate 1 °C/min. Upon heating, an endothermic peak was observed about 63 °C, which independent concentration. total energy defined area found be linear function On other hand, when samples 90 broad...

It was observed that the polyurethane shape memory polymer (SMP) loses its fixing capability after being exposed in air at room temperature for several days. A significant indication this change is continuous decrease of glass transition (Tg) polyurethane. Accompanying Tg, uniaxial tensile behaviour also changes. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) tests were carried out to find cause behind phenomenon. Moisture concluded as main reason. mathematical...

Thermally induced gelation was studied for aqueous solutions of methylcellulose with a substitution degree 1.8 and molecular weight 310 000. The dynamic viscoelastic microcalorimetric properties were measured as functions temperature polymer concentration. An attempt made to elucidate the validity scaling laws mechanism involved in thermoreversible methylcellulose. For given high concentration methlycellulose, gel elasticity evolved temperature, but it did not obey single law. At 70 °C,...

A series of phosphorus-doped titania samples with different phosphorus contents have been prepared by a simple, modified sol−gel method. The obtained were characterized X-ray diffraction spectrometry, Brunauer−Emmett−Teller surface area, differential thermal analysis-thermogravimetry, photoelectron spectroscopy, Fourier transform infrared Raman and UV−vis diffuse reflectance the photodegradation methylene blue (MB) on was tested under both UV visible light irradiation. It found that doped...