Thermoresponsive Nanogels Based on Different Polymeric Moieties for Biomedical Applications

Nanogels, or nanostructured hydrogels, are one of the most interesting materials in biomedical engineering. Nanogels are widely used in medical applications, such as in cancer therapy, targeted delivery of proteins, genes and DNAs, and scaffolds in tissue regeneration. One salient feature of nanogels is their tunable responsiveness to external stimuli. In this review, thermosensitive nanogels are discussed, with a focus on moieties in their chemical structure which are responsible for thermosensitivity. These thermosensitive moieties can be classified into four groups, namely, polymers bearing amide groups, ether groups, vinyl ether groups and hydrophilic polymers bearing hydrophobic groups. These novel thermoresponsive nanogels provide effective drug delivery systems and tissue regeneration constructs for treating patients in many clinical applications, such as targeted, sustained and controlled release

Thermoresponsive Nanogels Based on Different Polymeric Moieties for Biomedical Applications

Nanogels, or nanostructured hydrogels, are one of the most interesting materials in biomedical engineering. Nanogels are widely used in medical applications, such as in cancer therapy, targeted delivery of proteins, genes and DNAs, and scaffolds in tissue regeneration. One salient feature of nanogels is their tunable responsiveness to external stimuli. In this review, thermosensitive nanogels are discussed, with a focus on moieties in their chemical structure which are responsible for thermosensitivity. These thermosensitive moieties can be classified into four groups, namely, polymers bearing amide groups, ether groups, vinyl ether groups and hydrophilic polymers bearing hydrophobic groups. These novel thermoresponsive nanogels provide effective drug delivery systems and tissue regeneration constructs for treating patients in many clinical applications, such as targeted, sustained and controlled release

Chitosan/TPP microparticles obtained by microemulsion method applied in controlled release of heparin

AbstractThis work deals with the preparation of chitosan/tripolyphosphate microparticles (CHT/TPP) using microemulsion system based on water/benzyl alcohol. The morphology of the microparticles was evaluated by scanning electron microscopy (SEM). The microparticles were also characterized through infrared spectroscopy (FTIR) and wide-angle X-ray scattering (WAXS). The morphology and crystallinity of microparticles depended mainly on CHT/TPP ratio. Studies of controlled release of HP were evaluated in distilled water and in simulated gastric fluid. Besides, the profile of HP releasing could be tailored by tuning the CHT/TPP molar ratio. Finally, these prospective results allow the particles to be employed as site-specific HP controlled release system

Sub-micron sized saccharide fibres via electrospinning

In this work, the production of continuous submicron diameter saccharide fibres is shown to be possible using the electrospinning process. The mechanism for the formation of electrospun polymer fibres is usually attributed to the physical entanglement of long molecular chains. The ability to electrospin continuous fibre from a low molecular weight saccharides was an unexpected phenomenon. The formation of sub-micron diameter “sugar syrup” fibres was observed in situ using high speed video. The trajectory of the electrospun saccharide fibre was observed to follow that typical of electrospun polymers. Based on initial food grade glucose syrup tests, various solutions based on combinations of syrup components, i.e. mono-, di- and tri-saccharides, were investigated to map out materials and electrospinning conditions that would lead to the formation of fibre. This work demonstrated that sucrose exhibits the highest propensity for fibre formation during electrospinning amongst the various types of saccharide solutions studied. The possibility of electrospinning low molecular weight saccharides into sub-micron fibres has implications for the electrospinability of supramolecular polymers and other biomaterial

Marine Polysaccharides in Pharmaceutical Applications: An Overview

The enormous variety of polysaccharides that can be extracted from marine plants and animal organisms or produced by marine bacteria means that the field of marine polysaccharides is constantly evolving. Recent advances in biological techniques allow high levels of polysaccharides of interest to be produced in vitro. Biotechnology is a powerful tool to obtain polysaccharides from a variety of micro-organisms, by controlling the growth conditions in a bioreactor while tailoring the production of biologically active compounds. Following an overview of the current knowledge on marine polysaccharides, with special attention to potential pharmaceutical applications and to more recent progress on the discovering of new polysaccharides with biological appealing characteristics, this review will focus on possible strategies for chemical or physical modification aimed to tailor the final properties of interest

Thermoresponsive Nanogels Based on Different Polymeric Moieties for Biomedical Applications

Nanogels, or nanostructured hydrogels, are one of the most interesting materials in biomedical engineering. Nanogels are widely used in medical applications, such as in cancer therapy, targeted delivery of proteins, genes and DNAs, and scaffolds in tissue regeneration. One salient feature of nanogels is their tunable responsiveness to external stimuli. In this review, thermosensitive nanogels are discussed, with a focus on moieties in their chemical structure which are responsible for thermosensitivity. These thermosensitive moieties can be classified into four groups, namely, polymers bearing amide groups, ether groups, vinyl ether groups and hydrophilic polymers bearing hydrophobic groups. These novel thermoresponsive nanogels provide effective drug delivery systems and tissue regeneration constructs for treating patients in many clinical applications, such as targeted, sustained and controlled release