Controlled in vivo swimming of a swarm of bacteria-like microrobotic flagella.

In vivo imaging and actuation of a swarm of magnetic helical microswimmers by external magnetic fields (less than 10 mT) in deep tissue is demonstrated for the first time. This constitutes a major milestone in the field, yielding a generation of micrometer-scale transporters with numerous applications in biomedicine including synthetic biology, assisted fertilization, and drug/gene delivery.

Graphene-based electroresponsive scaffolds as polymeric implants for on-demand drug delivery.

Stimuli-responsive biomaterials have attracted significant attention in the field of polymeric implants designed as active scaffolds for on-demand drug delivery. Conventional porous scaffolds suffer from drawbacks such as molecular diffusion and material degradation, allowing in most cases only a zero-order drug release profile. The possibility of using external stimulation to trigger drug release is particularly enticing.

Design, engineering and structural integrity of electro-responsive carbon nanotube- based hydrogels for pulsatile drug release.

Triggerable drug delivery from polymeric implants offers the possibility to generate remote-controlled drug release profiles that may overcome the deficiencies of conventional administration routes (intravenous injections and oral administration) including the toxicity due to overdose and systemic administration. An electro-responsive delivery system was engineered to deliver drug molecules in a pulsatile manner, controlled by the on/off application of electric voltage. Pristine multi-walled carbon nanotubes (pMWNTs) were incorporated into a polymethacrylic acid (PMAA)-based hydrogel matrix by in situ radical polymerisation.

Electroresponsive polymer-carbon nanotube hydrogel hybrids for pulsatile drug delivery in vivo.

Drug release triggered by an external non-invasive stimulus is of great interest for the development of new drug delivery systems. The preparation of an electroresponsive multiwalled carbon nanotube/poly(methylacrylic acid) (MWNT/PMAA)-based hybrid material is reported. The hydrogel hybrids achieve a controlled drug release upon the ON/OFF application of an electric field, giving rise to in vitro and in vivo pulsatile release profiles.

Purified graphene oxide dispersions lack in vitro cytotoxicity and in vivo pathogenicity.

Prompted by the excitement from the description of single layer graphene, increased attention for potential applications in the biomedical field has been recently placed on graphene oxide (GO). Determination of the opportunities and limitations that GO offers in biomedicine are particularly prone to inaccuracies due to wide variability in the preparation methodologies of GO material in different laboratories, that results in significant variation in the purity of the material and the yield of the oxidation reactions, primarily the Hummers method used. Herein, the fabrication of highly pure, colloidally stable, and evenly dispersed GO in physiologically-relevant aqueous buffers in comparison to conventional GO is investigated.

Modulation of imprinting efficiency in nanogels with catalytic activity in the Kemp elimination.

The interactions between the template and the functional monomer are a key to the formation of cavities in the imprinted nanogels with high molecular recognition properties. Nanogels with enzyme-like activity for the Kemp elimination have been synthesized using 4-vinylpyridine as the functional monomer and indole as the template. The weak hydrogen bond interaction in the complex is shown to be able to induce very distinctive features in the cavities of the imprinted nanogels.

Tuning molecular recognition in water-soluble nanogels with enzyme-like activity for the kemp elimination.

The synthesis and characterization of water-soluble imprinted nanogels with enzyme-like activity in the Kemp elimination is reported together with studies that demonstrate how the recognition properties, morphology, and catalytic activity of the nanoparticles can be tuned by the use of surfactants, such as Tween 20. A detailed kinetic investigation is carried out, which shows clear evidence of saturation kinetics and rule out the effects of mass transfer. This is supported by characterization of the polymeric materials that confirms the morphological changes resulting from the use of surfactants.

The first example of molecularly imprinted nanogels with aldolase type I activity.

The molecular-imprinting approach was used to obtain a nanogel preparation capable of catalysing the cross-aldol reaction between 4-nitrobenzaldehyde and acetone. A polymerisable proline derivative was used as the functional monomer to mimic the enamine-based mechanism of aldolase type I enzymes. The diketone template used to create the cavity was designed to imitate the intermediate of the aldol reaction and was bound to the functional monomer using a reversible covalent interaction prior to polymerisation.