Recent Progress in the Synthesis and Biomedical Properties of Natural Biopolymer Composites.

Background: Natural biopolymers have drawn extensive attention because of their great biocompatibility, biodegradability, renewability, and the availability of various reactive functional groups for modifying and introducing novel components. In the last few years, numerous natural biopolymer composites have been exploited to improve their physical and chemical properties and add new functionalities.

Methods: Herein, we summarize the current progress in three common classes of natural biopolymer-based composites, including alginate, chitosan, and gelatin.

Cellulose-based Nanocarriers as Platforms for Cancer Therapy.

Cellulose is an important environmentally-friendly renewable polymer on the earth. Cellulose has been widely used as feedstocks for the synthesis of biomaterials, biofuels and biochemicals. Recently, cellulose and cellulose derivatives have received intense attention in biomedical applications, such as tissue engineering, scaffold, artificial blood vessel, skin grafts, artificial skin, drug carrier, and chronic skin diseases, many of which are somehow related to cancer therapy.

Microwave-Assisted Hydrothermal Synthesis of Cellulose/Hydroxyapatite Nanocomposites.

In this paper, we report a facile, rapid, and green strategy for the synthesis of cellulose/hydroxyapatite (HA) nanocomposites using an inorganic phosphorus source (sodium dihydrogen phosphate dihydrate (NaH₂PO₄·2H₂O)), or organic phosphorus sources (adenosine 5'-triphosphate disodium salt (ATP), creatine phosphate disodium salt tetrahydrate (CP), or D-fructose 1,6-bisphosphate trisodium salt octahydrate (FBP)) through the microwave-assisted hydrothermal method. The effects of the phosphorus sources, heating time, and heating temperature on the phase, size, and morphology of the products were systematically investigated. The experimental results revealed that the phosphate sources played a critical role on the phase, size, and morphology of the minerals in the nanocomposites.

The microwave-assisted ionic-liquid method: a promising methodology in nanomaterials.

In recent years, the microwave-assisted ionic-liquid method has been accepted as a promising methodology for the preparation of nanomaterials and cellulose-based nanocomposites. Applications of this method in the preparation of cellulose-based nanocomposites comply with the major principles of green chemistry, that is, they use an environmentally friendly method in environmentally preferable solvents to make use of renewable materials. This minireview focuses on the recent development of the synthesis of nanomaterials and cellulose-based nanocomposites by means of the microwave-assisted ionic-liquid method.

Microwave synthesis of cellulose/CuO nanocomposites in ionic liquid and its thermal transformation to CuO.

The purpose of this study is to develop a green strategy to synthesize the cellulose-based nanocomposites and open a new avenue to the high value-added applications of biomass. Herein, we reported a microwave-assisted ionic liquid route to the preparation of cellulose/CuO nanocomposites, which combined three major green chemistry principles: using environmentally friendly method, greener solvents, and sustainable resources. The influences of the reaction parameters including the heating time and the ratio of cellulose solution to ionic liquid on the products were discussed by X-ray powder diffraction, Fourier transform infrared spectrometry, and scanning electron microscopy.

Nanocomposites of cellulose/iron oxide: influence of synthesis conditions on their morphological behavior and thermal stability.

Nanocomposites of cellulose/iron oxide have been successfully prepared by hydrothermal method using cellulose solution and Fe(NO3)3·9H2O at 180 °C. The cellulose solution was obtained by the dissolution of microcrystalline cellulose in NaOH/urea aqueous solution, which is a good system to dissolve cellulose and favors the synthesis of iron oxide without needing any template or other reagents. The phases, microstructure, and morphologies of nanocomposites were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectra (EDS).

Isolation and characterization of hemicelluloses extracted by hydrothermal pretreatment.

The dewaxed sample from Triploid of Populus tomentosa Carr. was extracted by using organic alkaline solvent (Dimethylformamide, DMF) via hydrothermal pretreatment. Neutral sugar compositions and molecular weight analysis demonstrated that the hemicellulosic fractions with a higher Uro/Xyl ratio, namely the more branched hemicelluloses, had higher molecular weights.

Recent progress on fabrication of calcium-based inorganic biodegradable nanomaterials.

Calcium-based inorganic biodegradable nanomaterials (CIBNs) including calcium phosphate, hydroxyapatite (HA), calcium silicate, calcium carbonate, and calcium sulfate, are important materials and have been widely used in biomedical field. Although CIBNs have been intensively studied, there are only a few synthesis methods that showed promising characteristics for practical applications. Here, we intend to review recent progress in the synthesis of the CIBNs including both patents and papers.

Recent Progress on Fabrication of Calcium-Based Inorganic Biodegradable Nanomaterials.

Calcium-based inorganic biodegradable nanomaterials (CIBNs) including calcium phosphate, hydroxyapatite (HA), calcium silicate, calcium carbonate, and calcium sulfate, are important materials and have been widely used in biomedical field. Although CIBNs have been intensively studied, there are only a few synthesis methods that showed promising characteristics for practical applications. Here, we intend to review recent progress in synthesis of the CIBNs including both patents and papers.

Rapid microwave-assisted synthesis and characterization of cellulose-hydroxyapatite nanocomposites in N,N-dimethylacetamide solvent.

Preparation of nanocomposites was carried out using microcrystalline cellulose, CaCl(2), and NaH(2)PO(4) in N,N-dimethylacetamide (DMAc) solvent by a microwave-assisted method at 150 degrees C. XRD results showed that the nanocomposites consisted of cellulose and hydroxyapatite (HA). The cellulose existed as a matrix in the nanocomposites.

Microwave-assisted one-step synthesis of polyacrylamide-metal (M = Ag, Pt, Cu) nanocomposites in ethylene glycol.

Polyacrylamide-metal (M = Pt, Ag, Cu) nanocomposites with metal nanoparticles homogeneously dispersed in the polymer matrix have been successfully prepared with the corresponding metal salt and acrylamide monomer in ethylene glycol by microwave heating. This method is based on the single-step simultaneous formation of metal nanoparticles and polymerization of the acrylamide monomer, leading to a homogeneous distribution of metal nanoparticles in the polyacrylamide matrix. Ethylene glycol acts as both a reducing reagent and a solvent, thus no additional reductant is needed.