Contact: Contact: International Center for Materials Nanoarchitectonics (MANAMANA), Nakata (ex. 8806)), Nakata (ex. 8806)

Venue: Seminar Room #431, MANA Bldg., NamikiDate: Time:

Scanning probe microscopy in fluid environments: From nanocells to red blood cells

Dr. John A. DagataNational Institute of Standards & Technology

Scanning probe microscopy (SPM) in fluid offers unprecedented capabilities for imaging, characterizing, and manipulating surfacechemical reactions and biomaterial assemblies with nanometer-scale resolution. Following a brief introduction to SPM principles and operational modes, I will describe how one may go about designing experiments to take advantage of unique capabilities ofthe SPM in order to explore a wide range of research questions. This discussion will involve two very different examples: First, a strategy developed over the past several years to understand the physical and chemical properties of the electrochemical nanocellwill be reviewed. The nanocell concept refers to the formation of a stable water meniscus resulting from the highly non-uniform electric field that arises when voltage is applied across the tip-sample junction in humid air. Oxyanions from water molecules within the junction are transported through the growing oxide film. This simple scheme leads to oxidation of the substrate on a scale determined by the dimensions of the water meniscus and forms the basis for patterning functional nanostructures for a variety of applications. Second, I will illustrate how SPM-based imaging and force measurements can be integrated into physical characterization approaches for soft materials such as casein micelles, nanocellulose, red blood cells, and nanoparticle delivery systems (NDS) which are of interest in healthcare and environmental research applications. The availability of quantitative measurements and standards will accelerate the translation of nanotechnology-based drug delivery and medical devices from the laboratory to the clinic, increasing the likelihood that these approaches will ultimately be of direct human benefit.

15:30-16:1515:30-16:15Dec 11th ThursdayDec 11th Thursday