The Johnson Research Group is inspired by the sentiment "If you can't sense it, you can't control it."

Background: The composition, structure, and properties of fluids and materials are inputs, outputs, states, and quality signatures of many physical, chemical, and biological processes.

Challenges: Measuring the composition, structure, and properties of fluids and materials before, during, and after processing is essential to quality assurance and control in various industries (e.g., pharmaceutical, medical diagnostics, environmental monitoring).

However, this requires analytical platforms for rapid and robust measurement in practical matrices, such as crude product mixtures, and practical processing formats, such as those based on high-throughput batch or continuous flow formats.

Our Research:  The creation of scalable, high-throughput, automated analytical techniques for measuring the composition, structure, and properties of fluids and materials in practical processing formats requires innovations in sensing and data analytics.  Our research is characterized by an iterative process of modeling, making, and measuring. In particular, we are focused on studying and creating:

  • 1) chemical sensors, biosensors, and sensor-embedded systems;

  • 2) sensor-based techniques for characterization of material structure and material properties;

  • 3) hierarchical, multi-material, bottom-up manufacturing processes; and

  • 4) automated platforms for high-throughput material characterization and discovery.

Consequently, the Johnson Research Group is focused on advancing instrumentation for biosensing, material structure-property sensing, and automated characterization.  We are also interested in establishing data analytics for classification of sensor time-series and spectral data, surface functionalization methods, molecular self-assembly processes, functional materials (e.g., stimuli-responsive, dielectric, piezoelectric), robotic embedding and conformal 3D printing techniques, and biosensing measurement techniques for continuous monitoring applications.

Sensing: While sensors widely vary regarding sensing principle, measurement capabilities, form factor, and size, which informs their capabilities and application, our research is focused on the creation of robust multi-scale sensors that facilitate continuous in-situ composition, structure, or property sensing in complex matrices. We focus on the realization of highly-integrated sensors (e.g., embedded of form-fitting) and complementary sample preparation-free and label-free measurement protocols. Given their versatility, sensitivity, and manufacturability, our lab is highly interested and experienced in the design, modeling, fabrication and application of impedimetric sensors, which range from thin film, cantilever, and fiber form factors

Processes and Characterization Techniques: Our relies heavily on 3D scanning and micro-extrusion additive manufacturing processes, electrochemical and dielectric impedance analysis, and traditional characterization and bioanalytical techniques.

Neuroscience: The Johnson Group is particularly interested in sensing and biofabrication applications that contribute to neuroscience.  We are specifically interested in the fabrication of bio-inspired scaffolds for nerve regeneration, instrumented microphysiological neural systems, and neural interface. Applications include disease modeling, nerve repair, neuromodulation, brain-machine interface, and pain monitoring.