Starch-based completely biodegradable polymer materials

Microparticle delivery system is accepted as are reliable. Mean to delivery the drug to the target site with specificity,. The drug should be delivered to specific target site at a rate and concentration that provides optimum therapeutic efficacy and reducing the side effect to minimum. Microspheres are empty spherical particles, the particle size is less than 200 mm. Microspheres are free flowing powder consisting of natural and synthetic polymers. They have the potential controlled release drug. Polymers are the most important things of pharmaceutical drug delivery. There are many kind of polymers which varying the properties available those days for use in different pharmaceutical applications. Polymers use in the preparation of microspheres is the synthetic and natural polymers. Synthetic polymers are acrolein, poly anhydrides, methyl meth acrylate, lactides, and glycosides. Natural polymers are albumin, gelatin, collagen, agarose, chitosan, carragenene. Microspheres are the free flowing powders consist of protein and synthetic polymers having a particle size ranging from 1 ? 1000 micrometer. Microspheres are prepared by several techniques but the choice of method depends upon the drug. The polymers used and duration of action required. The evaluation parameters of microspheres are micromeritic properties particle size and shape, swelling index, tapped density, drug loading efficiency. In coming days by combining numerous other sceniorio, we will find the microspheres in novel drug delivery. Specifically in disease cell sorting diagnostics, gene and genetic materials, safe targeted and effective in vivo delivery and supplements a tiny interpretation of diseased organ and tissue in the body. Keywords: Microencapsulation, novel drug delivery, synthetic and natural polymers, duration of action.

Most commercialized wound dressings are polymer-based. Synthetic and natural polymers have been utilized widely for the development of wound dressings. However, the use of natural polymers is limited by their poor mechanical properties, resulting in their combination with synthetic polymers and other materials to enhance their mechanical properties. Natural polymers are mostly affordable, biocompatible, and biodegradable with promising antimicrobial activity. They have been further tailored into unique hybrid wound dressings when combined with synthetic polymers and selected biomaterials. Some important features required in an ideal wound dressing include the capability to prevent bacteria invasion, reduce odor, absorb exudates, be comfortable, facilitate easy application and removal as well as frequent changing, prevent further skin tear and irritation when applied or removed, and provide a moist environment and soothing effect, be permeable to gases, etc. The efficacy of polymers in the design of wound dressings cannot be overemphasized. This review article reports the efficacy of wound dressings prepared from a combination of synthetic and natural polymers.

Poly (vinyl alcohol) and hyaluronic acid hydrogels as potential biomaterial systems - A comprehensive review

Polymer blends and composites from renewable resources

Advances in Drug Delivery

Polymer contamination with the advent of fast industrialization has become one of the serious threat to the natural environment. Due to lack of proper knowledge, poor waste management practice and unavailability of potential microbial strains, preference toward the biodegradable manmade and natural polymers. The prevalent occurrence of synthetic polymers is related to industrialization and domestic practices which affect the marine and terrestrial ecosystems. Scientific approaches exploited for polymer degradation include physical, chemical and biological treatments. Among them, biodegradation serves as eco-friendly approach to remediate polluted environment using living organisms. In this chapter biodegradation of natural (cellulose, hemicelluloses and lignin), synthetic (polyurethane, polyethylene succinate, polycaprolactone, polyvinyl alcohol and polyethylene) polymers and associated factors that influence the polymer biodegradation process have been discussed.

Electrospinning is one of the techniques to produce structured polymeric fibers in the micro or nano scale and to generate novel materials for biomedical proposes. Electrospinning versatility provides fibers that could support different surgical and rehabilitation treatments. However, its diversity in equipment assembly, polymeric materials, and functional molecules to be incorporated in fibers result in profusion of recent biomaterials that are not fully explored, even though the recognized relevance of the technique. The present article describes the main electrospun polymeric materials used in oral applications, and the main aspects and parameters of the technique. Natural and synthetic polymers, blends, and composites were identified from the available literature and recent developments. Main applications of electrospun fibers were focused on drug delivery systems, tissue regeneration, and material reinforcement or modification, although studies require further investigation in order to enable direct use in human. Current and potential usages as biomaterials for oral applications must motivate the development in the use of electrospinning as an efficient method to produce highly innovative biomaterials, over the next few years. Impact statement Nanotechnology is a challenge for many researchers that look for obtaining different materials behaviors by modifying characteristics at a very low scale. Thus, the production of nanostructured materials represents a very important field in bioengineering, in which the electrospinning technique appears as a suitable alternative. This review discusses and provides further explanation on this versatile technique to produce novel polymeric biomaterials for oral applications. The use of electrospun fibers is incipient in oral areas, mainly because of the unfamiliarity with the technique. Provided disclosure, possibilities and state of the art are aimed at supporting interested researchers to better choose proper materials, understand, and design new experiments. This work seeks to encourage many other researchers-Dentists, Biologists, Engineers, Pharmacists-to develop innovative materials from different polymers. We highlight synthetic and natural polymers as trends in treatments to motivate an advance in the worldwide discussion and exploration of this interdisciplinary field.

Chemical enhanced oil recovery (EOR) processes are usually used as additives for hydrocarbon production due to its simplicity and relatively reasonable additional production costs. Polymer flooding uses polymer solutions to increase oil recovery by decreasing the water/oil mobility ratio by increasing the viscosity of the displacing water. The commonly used synthetic water-soluble polymer in EOR application is partially hydrolyzed polyacrylamide (HPAM). However, synthetic polymers in general are not attractive because of high cost, environmental concerns, limitation in high temperature, and high-salinity environment. Guar gum is an environmentally friendly natural water-soluble polymer available in large quantities in many countries and widely used in various applications in the oil and gas industry especially in drilling fluids and hydraulic fracturing operations; however, very limited studies investigated on guar as a polymer for EOR and no any study investigated on its uses in high-temperature and high -salinity reservoirs. The objective of this study is to confirm the use of guar gum as a natural polymer for EOR applications in sandstone reservoirs and investigate its applicability for high-temperature and high-salinity reservoirs. The study experimentally investigated rheological characteristics of a natural polymer obtained from guar gum with consideration of high temperature (up to 210 °F) and high salinity (up to 20% NaCl) and tested the guar solution as EOR polymer. The results of this study show that the guar solution can be used as an environmentally friendly polymer to enhance oil recovery. Based on the results, it can be concluded that guar gum shows shear-thinning behavior and strongly susceptible to microbial degradation but also shows a very good properties stability in high temperature and salinity, where in low shear rate case, about 100 cp viscosity can be achieved at 210 °F for polymer prepared in deionized water. Guar polymer shows good viscosity in the presence of 20% NaCl where the viscosity is acceptable for temperature less than 190 °F. Also, the flooding experiment shows that the recovery factor can be increased by 16%.

6 - Nanoengineered polymeric biomaterials for drug delivery system

Graphene-Based Materials for Inhibition of Wound Infection and Accelerating Wound Healing

Marine and terrestrial humic acids are thought to differ in structural composition owing to differences in precursors and formation pathways. It has been proposed that marine humic acids are formed by the polymerization of sugars and amino acids (the melanoidin pathway) while terrestrial humic acids result primarily from the condensation of lignin-derived phenols and amino acids. In this study, four marine and three terrestrial humic acids have been isolated, and a series of polymers have been made by the reaction of either glucose or catechol with alanine or ammonia. Chemical and spectroscopic measurements of the natural and synthetic polymers have been made, including elemental analysis, carbon isotope ratios and IR, UV-visible, UV-fluorescence, and ESR scans. In additi n, degradative analyses of marine and terrestrial humic acids together with the synthetic polymers have been performed to determine (1) if characteristic structural differences exist between marine and terrestrial humic acids and (2) if similarities between the degradative products of synthetic and natural polymers reflect biologic precursors and reaction pathways. End_of_Article - Last_Page 704------------

In recent years, a technological breakthrough in the pharmaceutical and biomedical fields have been reflected in the development of more complex, safe and effective dosage forms to improve the administration, delivery, disposition and stability of drugs, as well as at creating more biocompatible and biodegradable materials. As a result, modified release devices and functional coatings which improve the effectiveness and efficacy of drugs have been generated. This advancement has been achieved by physical or chemical modification of natural or semisynthetic polymers which stabilize and protect drugs against harsh environmental factors. Therefore, the development of novel excipients with a high functionality and robustness has become an important quest. Among these materials, polyvinyl alcohol is one of the most versatile and biocompatible, since by chemical or physical modification its properties are modulated, improving drug stability, drug targeting, and ensures patient compliance. Freezing-thawing cycles, heat treatment and formation of composites are the most significant physical modifications to improve the performance of polyvinyl alcohol. On the other hand, the chemical modifications by cross-linking with aldehydes, carboxylic acids, sodium tetraborate, epichlorohydrin have enhanced the physical and mechanical properties, such as the oil sorption ability, oxygen and waterproof characteristics, mechanical strength, drug diffusion and rate of swelling. Key words: Polyvinyl alcohol, composites, crosslinking, pharmaceutical and biomedical applications.

The tremendous risk of climate change and environmental problems has drastically endangered the survival and development of human society, which certainly demand modern technologies that require high-performance materials with superior properties. Photocatalysis is a promising, greener, and eco-friendly technology for pollution remediation, energy conversion, and chemical synthesis. Moreover, this technology has emerged as a powerful tool to design and in the development of engineered materials. In this association, functionalized polymers and their (nano) composites are not only used as fillers in polymer matrices but also play a significant role as hosts or supporting materials for inorganic metals and semiconductors (TiO2, ZnO, Fe2O3, and so on). As efficient supporting materials in photocatalysis, functionalized polymeric composites derived either from natural or synthetic polymers are gaining much attention from governments, industries, and academia on the account of their low cost, environmental compatibility, and replacement capability for petroleum-derived products. This chapter provides a comprehensive understanding for obtaining photocatalytic organic/inorganic hybrid (nano) composites from natural and synthetic functionalized polymers and their wastewater treatment applications. Two different categories of functionalized polymers, namely, (i) natural polymers and (ii) synthetic polymers, and their composite materials along with their recent advancement in wastewater treatment by light-responsive photocatalysis are figured out.

Chapter 10 - Biodegradable polymers as packaging materials

Ancient fibrous biomaterials from silkworm protein fibroin and spider silk blends: Biomechanical patterns