Volume 8 Issue 6, June 2009

Robert Langer has spent more than 30 years working with biomaterials and has seen their development from simple implants to complex multifunctional interfaces with the body. He shares his vision of the field's origins and what the future holds with Nature Materials.

Sustained gene knockdown by the aid of a well-known biodegradable polymer has shown that old materials can still be used to solve new problems.

Spray-coating of multilayer films on fibre mats yields conformal coatings, opening up new possibilities for the fabrication of protective clothing and reactive membranes.

Nanoparticles containing a silver iodine core and a polymer shell have superionic conductance even near room temperature, showing promise for a new generation of electrochemical devices.

By using light to control the degradation of hydrogel components in space and time, researchers have generated a tool to help them reconstruct functional biological tissues in a culture dish.

Advances in the functionality of multifunctional nanoparticles push their potential for the remote detection and treatment of cancer nearer to real-life patient care.

Fe-based superconductors have attracted tremendous interest recently. New evidence on BaFe₂As₂ shows that chemical doping and pressure, both of which induce superconductivity, distort the lattice in similar ways. The result provides important information in the quest for an understanding of the mechanism behind superconductivity.

Silver iodide is a well-known ionic conductor. However, it shows superionic conductivity only in its high-temperature phase (above∼150 ^∘C). It is now demonstrated that various sizes of nanoparticles can be synthesized for which the superionic phase is stable down to ∼30 ^∘C. The results suggest promising applications in silver-ion-based electrochemical devices.

Metal–organic frameworks are highly porous materials that are promising for drug release and gas storage. A liquid-phase-epitaxy approach that prevents interpenetration and retains the pore size is now proposed.

Multiferroics offer intriguing opportunities for sensing and information storage applications, although their integration into electronic devices has been difficult owing to a lack of suitable electronic control. Electric modulation of conduction is now achieved for a doped multiferroic, resulting in complete control over the ferroelectric state itself.

Stretchable electronics enables applications on arbitrary curved surfaces or on movable parts to be made. Based on a new technique for printing with carbon nanotube pastes, stretchable active matrix displays containing integrated electronic circuits are now realized.

The high capacity and energy densities of lithium sulphur batteries make them promising for applications, but their widespread realization has been hindered by problems at the interface between the cell components. A conductive mesoporous carbon–sulphur cathode framework capable of constraining sulphur growth and generating electrical contact to the insulating sulphur is now reported.

The size distribution of polymer vesicles and phospholipids is usually polydisperse as there are no selection rules for the overall size. A method combining photolithography and molecular self-assembly can now produce giant polymer vesicles with controlled and narrow size distributions.

A process based on spray-assisted layer-by-layer deposition produces conformal coatings on individual fibres within the bulk porous substrate. Additional processing creates a sublayer with properties that differ from the substrate. The method is used to fabricate a material that acts as both a toxin barrier and a photocatalyst.

Free-standing nanoparticle superlattices offer interesting possibilities for the design of devices free from undesired effects of substrates. DNA can now be used to obtain superlattices with control over interparticle spacing, offering an alternative perspective on the synthesis of nanoparticle solids.

Concerns over safety and the inability to control release have hampered progress towards instilling siRNA into mucosal tissue for protection against and treatment of human disease. Nanoparticles made from FDA-approved polymers have now been loaded with large amounts of siRNA and topically applied to vaginal mucosa leading to sustained gene silencing.

The biomaterials field is booming, thanks to unprecedented levels of understanding of biological systems and their interfaces with materials. Advances in the lab should make major impacts on patient care soon. We look at the history, current status and future prospects for this dynamic field.