Professor Silvana Andreescu and her research group study bioactive nanostructures, which consist of simple chemical and biological molecules that are assembled in precise proportions to form specific structures.
“Bioactive nanostructures are needed in a wide range of applications, especially in medical diagnostics and in environmental and food monitoring,” says Andreescu . The use of bioactive nanostructures is prevalent in the medical field, where they serve as building blocks for making implantable microdevices, such as those used to deliver drugs to specific organs in a patient’s body.
An expert in biosensing technology, Andreescu designs biosensors to perform specific functions by manipulating the components within the bioactive nanostructures. Examples of biosensing devices include wearable biosensors, functional contact lenses, environmental filters, smart screens and intelligent packaging. Depending on their specific functions, these devices allow users to monitor personal physiological biomarkers, such as blood pressure levels, or external conditions, such as exposure to environmental pollutants.
Andreescu has already patented several of her biosensor prototypes, including smart labels for food packaging that indicate food quality and safety. For example, a freshness sensor label can be applied to meat and poultry products. The ink color on the label will change according to the condition of the meat, turning from orange to gray when the meat is no longer fresh.
Smart food labels have been available for a few years now, but Andreescu’s smart label prototypes are far more sophisticated — one can authenticate various food products and detect antioxidant levels, while another can measure exposure to bisphenol A (BPA).
Manufacturing Affordable, Portable, Easy-to-Use Biosensors
Now, with funding from the National Science Foundation, Andreescu is developing a process for the large-scale manufacturing of functional bioactive nanostructures on flexible and inexpensive substrates, such as paper and plastic, using two- and three-dimensional printing techniques. This will enable the development of a new class of biosensing devices that are easy to use, portable and inexpensive.
“We are also designing our devices to be convenient to use, so that everything needed for analysis is confined within the device body," “she explains. The device body consists of a bioactive nanostructure interface, together with either an electronic circuit or a spectral-based analysis system. Upon exposure to the external environment, the circuit or analysis system can detect changes occurring to the nanomaterials and transmit those changes as output signals.
One challenge Andreescu faces is the need to maintain the functional properties and structural integrity of the nanoparticles within the device body.
“Most of the work that we do focuses on stabilizing the biological molecules, which are inherently sensitive to the environment,” she explains. A critical part of this work involves engineering a “cage” that can protect the biomolecules and maintain their activity under actual environmental conditions.
Andreescu is also taking the next step toward commercialization.
“There are many exciting applications of this technology, and we can tailor our device designs to address a specific need or market. My plan is to incorporate bioactive materials in commercial products and devices and to pursue real-world applications in the small, portable device market.”