Glyconanoparticles for biomedical applications

Over the past two decades, glycosylated nanoparticles (i.e., glyconanoparticles having sugar residues on the surface) received much attention for biomedical applications such as bioassays and targeted drug delivery. This minireview focuses on three aspects: (1) glycosylated gold nanoparticles, (2) glycosylated quantum dots, and (3) glyconanoparticles self-assembled from amphiphilic glycopolymers. The synthetic methods and the multivalent interactions between glyconanoparticles and lectins is shortly illustrated.     

An AC electroosmotic micropump for circular chromatographic applications

Flow rates of up to 50 microm s(-1) have been successfully achieved in a closed-loop channel using an AC electroosmotic pump. The AC electroosmotic pump is made of an interdigitated array of unequal width electrodes located at the bottom of a channel, with an AC voltage applied between the small and the large electrodes. The flow rate was found to increase linearly with the applied voltage and to decrease linearly with the applied frequency. The pump is expected to be suitable for circular chromatography for the following reasons: the driving forces are distributed over the channel length and the pumping direction is set by the direction of the interdigitated electrodes. Pumping in a closed-loop channel can be achieved by arranging the electrode pattern in a circle. In addition the inherent working principle of AC electroosmotic pumping enables the independent optimisation of the channel height or the flow velocity.     

Synthesis of water soluble, biodegradable, and electroactive polysaccharide crosslinker with aldehyde and carboxylic groups for biomedical applications

We report the synthesis and characterization of a polysaccharide crosslinker of tetraaniline grafting oxidized sodium alginate with large aldehyde and carboxylic groups. We demonstrate that this copolymer has the following properties: it is water soluble under any pH, biodegradable, electroactive, and noncytotoxic; it can self-assemble into nanoparticles with large active functional groups on the outer surface; it can crosslink materials with amino and aminoderivative groups like gelatin to form hydrogels, and thus the electroactivity is readily introduced to the materials. This copolymer has potential applications in biomedical fields such as tissue engineering, drug delivery, and nerve probes where electroactivity is required.     

Acoustic nanodrops for biomedical applications

Acoustic nanodrops are designed to vaporize into ultrasound-responsive microbubbles, which present certain challenges nonexistent for conventional nanoemulsions. The requirements of biocompatibility, vaporizability, and colloidal stability have focused research on perfluorocarbons. Shorter perfluorocarbons yield better vaporizability via their lower critical temperature, but they also dissolve more easily owing to their higher vapor pressure and solubility. Thus, acoustic nanodrops have required a trade-off between vaporizability and colloidal stability in vivo. The recent advent of vaporizable endoskeletal droplets, which are both colloidally stable and vaporizable, may have solved this problem. The purpose of this review is to justify this premise by pointing out the beneficial properties of acoustic nanodrops, providing an analysis of vaporization and dissolution mechanisms, and reviewing current biomedical applications.     

Emissive metallacages for biomedical applications

Owing to their appealing three-dimensional structures and tunable photophysical properties, emissive metallacages have been widely applied in recognition and sensing, adsorption and separation, catalysis, etc. Recently, the application of emissive metallacages in biomedical fields has emerged as a hot research topic, because multiple biological functionalities can be facilely integrated into metallacage-based platforms to deliver different functions. In this review, the applications of emissive ...     

Spintronic platforms for biomedical applications

Since the fundamental discovery of the giant magnetoresistance many spintronic devices have been developed and implemented in our daily life (e.g. information storage and automotive industry). Lately, advances in the sensors technology (higher sensitivity, smaller size) have potentiated other applications, namely in the biological area, leading to the emergence of novel biomedical platforms. In particular the investigation of spintronics and its application to the development of magnetoresistive (MR) biomolecular and biomedical platforms are giving rise to a new class of biomedical diagnostic devices, suitable for bench top bioassays as well as point-of-care and point-of-use devices. Herein, integrated spintronic biochip platforms for diagnostic and cytometric applications, hybrid systems incorporating magnetoresistive sensors applied to neuroelectronic studies and biomedical imaging, namely magneto-encephalography and magneto-cardiography, are reviewed. Also lab-on-a-chip MR-based platforms to perform biological studies at the single molecule level are discussed. Overall the potential and main characteristics of such MR-based biomedical devices, comparing to the existing technologies while giving particular examples of targeted applications, are addressed.     

Assessing the degradation profiles of a thermoresponsive polyvinyl alcohol (PVA)-based hydrogel for biomedical applications

Primary challenges associated with the design and success of polymeric biomedical devices are generally related to the control of the biomaterial in terms of degradability characteristics, sufficient processability characteristics, and required mechanical strength that may be altered during sterilization or manufacturing procedures. Polyvinyl alcohol-based thermoresponsive biomaterials provide a distinct advantage for biomedical applications as their physiochemical properties can be easily modified according to their desired use. In this work, we evaluated the thermal degradation characteristics of a polyvinyl alcohol (PVA)/polyethylene glycol (PEG)/polyvinylpyrrolidone (PVP) hydrogel that undergoes a steam sterilization autoclave cycle at 121°C to induce fluid-like behavior. FTIR was used to characterize the evolution of the area of the carbonyl region between 1800 and 1525 cm⁻¹. The carbonyl area increased at temperatures beyond 121°C which were used to accelerate the onset of degradation during both thermal oxidation and pyrolysis. The change in the carbonyl region was shown to correlate with respect to both temperature and time of exposure. The carbonyl region increased significantly in the presence of oxygen at temperatures above 150°C. Despite showing signs of thermal degradation at temperatures exceeding 150°C, our biomaterial was shown to be stable at 121°C during thermal degradation testing. Furthermore, bulk property analysis showed the hydrogel's mechanical and swelling properties were preserved even after being subject to multiple autoclave cycles beyond what would be experienced during a sterilization or clinical procedure.     

A review on electrospun nanofibers for multiple biomedical applications

Electrospinning is a well-known technique since 1544 to fabricate nanofibers using different materials like polymers, metals oxides, proteins, and many more. In recent years, electrospinning has become the most popular technique for manufacturing nanofibers due to its ease of use and economic viability. Nanofibers have remarkable properties like high surface-to-volume ratio, variable pore size distribution (10–100 nm), high porosity, low density, and are suitable for surface functionalization. Therefore, electrospun nanofibers have been utilized for numerous applications in the pharmaceutical and biomedical field like tissue engineering, scaffolds, grafts, drug delivery, and so on. In this review article, we will be focusing on the versatility, current scenario, and future endeavors of electrospun nanofibers for various biomedical applications. This review discusses the properties of nanofibers, the background of the electrospinning technique, and its emergence in chronological order. It also covers the various types of electrospinning methods and their mechanism, further elaborating the factors affecting the properties of nanofibers, and applications in tissue engineering, drug delivery, nanofibers as biosensor, skin cancer treatment, and magnetic nanofibers.     

Quantum dots-hydrogel composites for biomedical applications

Quantum dots-hydrogel composites are promising new materials that have attracted extensive attention due to their incomparable biocompatibility and acceptable biodegradability, leading to enormous potential applications for various fields. This review summarizes the recent advances in quantum dots-hydrogel composites with a focus on synthesis methods, including hydrogel gelation in quantum dots(QDs) solution, embedding prepared QDs into hydrogels after gelation, forming QDs in situ within the pr...     

Quantum dots-hydrogel composites for biomedical applications

Quantum dots-hydrogel composites are promising new materials that have attracted extensive attention due to their incomparable biocompatibility and acceptable biodegradability, leading to enormous potential applications for various fields. This review summarizes the recent advances in quantum dots-hydrogel composites with a focus on synthesis methods, including hydrogel gelation in quantum dots(QDs) solution, embedding prepared QDs into hydrogels after gelation, forming QDs in situ within the pr...     

Visible light-curable polymers for biomedical applications

Photocurable systems, which offer advantages such as microfabrication and in situ fabrication, have been widely used as dental restorative materials. Because the visible light-curable (VLC) system causes no biological damage, it is popular as a dental material and is being investigated by many researchers for other medical applications. Here, the principle of the VLC system is explained and recent progress in key components including photoinitiators, monomers, macromers, and prepolymers is discussed. Finally, biomedical applications for drug delivery and soft tissue engineering are reviewed. Considering the recent development of VLC systems, its importance in the field of medical applications is expected to continue to increase in the future.     

Multifunctional polymeric materials for biomedical applications

The work performed by our research group during the last few years in the area of bioerodible-biodegradable polymers as designed to the formulation of systems for the controlled delivery of drugs and as specific sorbents of uraemic toxins is broadly reviewed. In particular, attention has been focused on the strategies adopted in the preparation of functional polymers containing hydroxyl or carboxyl groups, suitable to establish specific bonding and non-bonding interactions with conventional and proteic drugs.     

Zwitterionically modified hydroxypropylcellulose for biomedical applications

Novel polyelectrolytes have been synthesized by grafting sulfobetaine side chains onto hydroxypropylcellulose backbone. Polymers with various degrees of grafting have been obtained. The polymers do not interact with model anionic, cationic and zwitterionic surfactants as found in fluorescence studies using pyrene as a molecular probe. Dynamic light scattering (DLS) studies indicated that in the graft polymer solution two types of polymers are present. The films were formed from the grafted polymers. Using atomic force microscopy (AFM) technique it was found that they are resistant to the adhesion of proteins and can be used for the preparation of antiadhesive surfaces which may find biomedical applications.     

Mass spectrometry imaging for biomedical applications

The development of technologies for mass spectrometry imaging is of substantial research interest. Mass spectrometry is potentially capable of providing highly specific information about the distribution of compounds in tissues, with high sensitivity. The in-situ analysis needed for tissue imaging requires MS to be performed under conditions different from the traditional ones, typically with intensive sample preparation and optimized for pharmaceutical applications. In this paper we critically review the current status of MS imaging with different methods of sample ionization and discuss the 3D and quantitative imaging capabilities which need further development, the importance of the multi-modal imaging, and the balance between the pursuit of high-resolution imaging and the practical application of MS imaging in biomedicine.     

Metal-organic framework-based nanomaterials for biomedical applications

In the past decade,nanoscale metal-organic frameworks(nMOFs) have drawn a great attention due to their high porosity,wide range of pore shapes,tunable frameworks and relatively low toxic.With the development of nanotechnology,many researchers studied the synthesis,characterization,functionalization and biotoxicity of nMOFs,and a more thorough understanding was developed about numerous nMOFs as promising platforms for biomedical applications.This review highlights the up-to-date progress of nMOFs...     

Plasmid DNA hydrogels for biomedical applications

In the last few years, our research group has focused on the design and development of plasmid DNA (pDNA) based systems as devices to be used therapeutically in the biomedical field. Biocompatible macro and micro plasmid DNA gels were prepared by a cross-linking reaction. For the first time, the pDNA gels have been investigated with respect to their swelling in aqueous solution containing different additives. Furthermore, we clarified the fundamental and basic aspects of the solute release mechanism from pDNA hydrogels and the significance of this information is enormous as a basic tool for the formulation of pDNA carriers for drug/gene delivery applications. The co-delivery of a specific gene and anticancer drugs, combining chemical and gene therapies in the treatment of cancer was the main challenge of our research. Significant progresses have been made with a new p53 encoding pDNA microgel that is suitable for the loading and release of pDNA and doxorubicin. This represents a strong valuable finding in the strategic development of systems to improve cancer cure through the synergetic effect of chemical and gene therapy.     

Stimulus-responsive polymeric nanoparticles for biomedical applications

Polymeric nanoparticles with unique properties are regarded as the most promising materials for biomedical applications including drug delivery and in vitro/in vivo imaging.Among them,stimulus-responsive polymeric nanoparticles,usually termed as intelligent nanoparticles,could undergo structure,shape,and property changes after being exposed to external signals including pH,temperature,magnetic field,and light,which could be used to modulate the macroscopical behavior of the nanoparticles.This paper reviews ...     

Stimuli responsive polymers for biomedical applications

Polymers that can respond to external stimuli are of great interest in medicine, especially as controlled drug release vehicles. In this critical review, we consider the types of stimulus response used in therapeutic applications and the main classes of responsive materials developed to date. Particular emphasis is placed on the wide-ranging possibilities for the biomedical use of these polymers, ranging from drug delivery systems and cell adhesion mediators to controllers of enzyme function and gene expression (134 references).