A comprehensive review on recent advances in preparation, physicochemical characterization, and bioengineering applications of biopolymers.

Biopolymers are mainly the polymers which are created or obtained from living creatures such as plants and bacteria rather than petroleum, which has traditionally been the source of polymers. Biopolymers are chain-like molecules composed of repeated chemical blocks derived from renewable resources that may decay in the environment. The usage of biomaterials is becoming more popular as a means of reducing the use of non-renewable resources and reducing environmental pollution produced by synthetic materials. Biopolymers' biodegradability and non-toxic nature help to maintain our environment clean and safe. This study discusses how to improve the mechanical and physical characteristics of biopolymers, particularly in the realm of bioengineering. The paper begins with a fundamental introduction and progresses to a detailed examination of synthesis and a unique investigation of several recent focused biopolymers with mechanical, physical, and biological characterization. Biopolymers' unique non-toxicity, biodegradability, biocompatibility, and eco-friendly features are boosting their applications, especially in bioengineering fields, including agriculture, pharmaceuticals, biomedical, ecological, industrial, aqua treatment, and food packaging, among others, at the end of this paper. The purpose of this paper is to provide an overview of the relevance of biopolymers in smart and novel bioengineering applications. Graphical abstract: The Graphical abstract represents the biological sources and applications of biopolymers. Plants, bacteria, animals, agriculture wastes, and fossils are all biological sources for biopolymers, which are chemically manufactured from biological monomer units, including sugars, amino acids, natural fats and oils, and nucleotides. Biopolymer modification (chemical or physical) is recognized as a crucial technique for modifying physical and chemical characteristics, resulting in novel materials with improved capabilities and allowing them to be explored to their full potential in many fields of application such as tissue engineering, drug delivery, agriculture, biomedical, food industries, and industrial applications.

Fabrication and characterization of dendrimer-functionalized mesoporous hydroxyapatite.

A successful synthesis of mesostructured hydroxyapatite (HAp) using cetyltrimethylammonium bromide and poly(amido amine) dendrimer porogens has been reported. A comparative study of physicochemical properties has also been performed. The formation of a single-phase hydroxyapatite crystal in synthesized HAp particles with an aspect ratio of 2.3 was revealed. The formation of the mesostructural nature of HAp was proven with a specific surface area (56-63 m(2)/g) and a certain pore size (4.7-5.5 nm), although there were significant differences between particles from surfactant micelle and dendrimer porogens. In addition, the surface modification of mesoporous HAp particles was carried out using poly(amido amine) dendrimer. The content and thickness of the dendrimer coating on particle surfaces were highly dependent on the pH. At pH 9 or greater, the coating thickness corresponded to at least a double layer of dendrimer, but it decreased sharply with decreasing pH from 9 to 6, in agreement with the protonation of amine groups in the dendrimer, indicating the strong interaction of nonionic dendrimer with HAp. The developed dendrimer-functionalized mesoporous hydroxyapatite materials may be applicable in biocomposite material and/or bone tissue engineering.

Self-assembly of surfactants: An overview on general aspects of amphiphiles.

Surfactants are molecules (ionic or nonionic) that upon adsorption at the air-water interface reduce surface tension of water. Therefore, surfactants are surface-active agents. Surfactants are normally amphiphilic molecules with a long hydrocarbon tail and a polar head group. The head group may be anionic, cationic or nonionic and accordingly the surfactants are classified as anionic, cationic or nonionic. There are some surface-active amphiphilic molecules that contain both anionic and cationic centers at the head group. These are called zwitterionic surfactants. Surfactants can also have two hydrocarbon chains attached to a polar head and are called double chain surfactants. Also, surfactants containing two hydrophobic and two hydrophilic groups, called "gemini" surfactants. The gemini surfactants can be thought of "twin" surfactants as being made up of two typical surfactant molecules chemically linked at or near the head group. Amphiphilic molecules can also have two head groups (both anionic, both cationic or one anionic and the other cationic) joined by hydrophobic spacer. These types of molecules are termed "bola-amphiphiles" commonly known as "bolaforms". Surface activity of these molecules depends on both the hydrocarbon chain length and the nature of head group(s). Amphiphiles with longer hydrocarbon chains are found to be more surface-active compared to those having shorter hydrocarbon tail. It is observed that amphiphiles with fluorocarbon chain are more surface-active than those with hydrocarbon chain. This is because the fluorocarbon chain is more hydrophobic than hydrocarbon chain.

Biomedical Application of Doxorubicin Coated Hydroxyapatite-Poly(lactide-co-glycolide) Nanocomposite for Controlling Osteosarcoma Therapeutics.

Nano drug delivery systems are widely used in cancer treatment nowadays. It is used to accomplish a remarkable drug therapeutic index to increase the efficacy of nanocomposites against cancer cells without affecting the other cells. Ceramic nanoparticles are well-known to carry chemotherapeutic drugs to the infected sites. Interest in them is aroused by their potential for application as promising biomaterials, especially in various orthopaedic applications. In the current study, Hydroxyapatite (HAp) was prepared by a simple in situ precipitation method and coated with a potent anticancer drug doxorubicin (DOX) using poly(lactide-co-glycolide) (PLGA) polymer. The interfacial strength of the composite is enhanced by the use of polymer in the nanocomposite preparation. An interaction between HAp particle and PLGA matrix has been noticed, which leads to improve the physicochemical properties of the prepared composites. Such a novel nanocomposite is further physicochemically characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Transmission Electron Spectroscopy (TEM) and Particle Size Distribution (PSD). In addition, the biocompatibility and the anticancer activity of the nanocomposite were evaluated by a colorimetric assay (MTT assay). The synthesized DOX-HAp-PLGA nanocomposite shows a significant cytotoxicity towards osteosarcoma cells, which may be potentially used as an anticancer agent against osteosarcoma diseases.

Synthesis and characterization of ultrafine poly(vinylalcohol phosphate) coated magnetite nanoparticles.

Nanosized magnetite (Fe3O4) particles showing superparamagnetism at room temperature have been prepared by controlled coprecipitation of Fe2+ and Fe3+ in presence of highly hydrophilic poly(vinylalcohol phosphate)(PVAP). The impact of polymer concentration on particle size, size distribution, colloidal stability, and magnetic property has been extensively studied. The aqueous suspension of magnetite, prepared using 1% PVAP solution is stable for four weeks at pH 5-8. X-ray diffractograms show the formation of nanocrystalline inverse spinel phase magnetite. Transmission Electron Microscopy confirmed well dispersed cubic magnetite particles of size of about 5.8 nm. Dynamic Light Scattering measurement shows narrow distribution of hydrodynamic size of particle aggregates. Infrared spectra of samples show strong Fe--O--P bond on the oxide surface. UV-visible studies show aqueous dispersion of magnetite formed by using 1% PVAP solution is stable at least for four weeks without any detoriation of particle size. Magnetization measurements at room temperature show superparamagnetic nature of polymer coated magnetite nanoparticles.

Chemical synthesis, characterization, and biocompatibility study of hydroxyapatite/chitosan phosphate nanocomposite for bone tissue engineering applications.

A novel bioanalogue hydroxyapatite (HAp)/chitosan phosphate (CSP) nanocomposite has been synthesized by a solution-based chemical methodology with varying HAp contents from 10 to 60% (w/w). The interfacial bonding interaction between HAp and CSP has been investigated through Fourier transform infrared absorption spectra (FTIR) and x-ray diffraction (XRD). The surface morphology of the composite and the homogeneous dispersion of nanoparticles in the polymer matrix have been investigated through scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. The mechanical properties of the composite are found to be improved significantly with increase in nanoparticle contents. Cytotoxicity test using murine L929 fibroblast confirms that the nanocomposite is cytocompatible. Primary murine osteoblast cell culture study proves that the nanocomposite is osteocompatible and highly in vitro osteogenic. The use of CSP promotes the homogeneous distribution of particles in the polymer matrix through its pendant phosphate groups along with particle-polymer interfacial interactions. The prepared HAp/CSP nanocomposite with uniform microstructure may be used in bone tissue engineering applications.