.jpg)
Image Credit: GaudiLab/Shutterstock.com
Smart surfaces are an emerging material technology that demonstrates the extraordinary ability to respond dynamically to changes in the environment via the incorporation of Stimuli-responsive polymers (SRPs) into the material surface. This advance in nano-biotechnology mimics the fundamental responsive characteristic of living systems to external stimuli, thus blurring the edges between organic and non-organic matter.
Scientists have replicated this natural phenomenon by forming synthetic materials from functional molecular building blocks. It is the integration of these building blocks which enables the surface to be stimulated by environmental variations, including changes in temperature, pH, light and electrical fields. Three valuable properties that result from this are the regulation of surface wettability, antimicrobial characteristics and the transformation of stimuli signals into an electrical response.
Hydrophobic Surfaces
The University College London has developed a smart polymer surface that exhibits the hydrophobic property of water repulsion. Inspiration has been taken from the waxy cuticle of leaves and replicated via nano and micro-structural surface patterns. The creation of such a material could have a colossal impact within the health sector. The repulsion of water droplets from the surface takes with it any dirt particles, bacteria, and viruses present, thus inspiring the title of “self-clean surfaces”. This could dramatically reduce the transmission of infections, particularly in hospitals where precious time is required to continuously sterilize surfaces.
Antimicrobial Surfaces
The application of stimuli-responsive polymers within healthcare is not limited to self-cleaning. A truly remarkable advancement in material technology has been the fabrication of surfaces which autonomously kill bacteria. The smart surfaces incorporate a highly specialized dye which, when exposed to light, react with oxygen, producing particles named “radicals”. These reactants attack surface bacteria, damaging crucial cellular components of the bacteria – ultimately killing the harmful microbe. The realization of this novel property will be crucial to the impediment of the bacterial resistance to antibiotics, an epidemic of increasing concern; dubbed by some as the “antibiotic apocalypse”. The application of this antimicrobial surface will instigate a vital strategic turning point, concentrating on the prevention of infection rather than cure.
Electrically Responsive Surfaces
The key competitive advantage currently strived for in the automotive industry is the ability to offer “intelligent features”. It is, therefore, no surprise that vehicle companies have so swiftly seized the opportunity to exploit smart surfaces. It is proposed that the electrical response to stimuli could be implemented into control panels which will remain blank until a hand is detected, the benefit of which would be the reduction of driver distraction. An additional benefit to such a feature would be a reduction in weight by replacing heavy controls, a huge benefit to companies under increasing pressure to reduce fuel consumption.
Future Research: Multi-Responsive Polymers
It is evident that significant development has been achieved in the realization of the potential applications of smart surfaces, exploiting properties such as water repulsion, bacterial resistance, and electrical response. However, the possibility of multi-responsive polymer surfaces is an area of research truly in its infancy stage. A multi-responsive polymer may display independent responses to each of the different forms of stimuli or react in a compound manner as a result of the combined effect of the stimuli.
In recent years, various studies have been carried out with a focus on variations in temperature and pH. A surface that reacts to both modes of stimuli has been achieved by combining temperature –sensitive PNIPA grafted chains with a pH-sensitive grafted polyacid counterpart. This form of smart surface has gained particular interest as the cooperative response very closely resembles that of a body’s response to a drug under specific temperature, pH and active concentration conditions and therefore could be a catalyst to advances in drug delivery.
Sources and Further Reading
Disclaimer: The views expressed here are those of the author expressed in their private capacity and do not necessarily represent the views of AZoM.com Limited T/A AZoNetwork the owner and operator of this website. This disclaimer forms part of the Terms and conditions of use of this website.