See the Capabilities & Expertise page for more information about opportunities to collaborate with us.

Instrumentation we built:

Microtensiometer. Custom-built instrument that uses microscale bubbles and drops to directly and rapidly measure dynamic surface tension for small sample volumes. Capillary sizes range from 10 to 200 micrometers. Pressure is imposed via a static or oscillating pressure head. Recent publications describe the microtensiometer, a scaling analysis describing how to analyze the timescales measured in the device, convection capabilities, and the capability to impose an oscillatory pressure head for interfacial rheology.

Pendant bubble apparatus. Custom-built instrument with real-time or high-speed visualization of bubble/droplet interface. Interface shape fitting is performed using a non-gradient based numerical algorithm that we developed.   The code has been incorporated into a graphical user interface for easy use and can be obtained from Professor Anna upon request.

Linear Translation Shear Cell. Custom-built microscale shear cell allowing a linear Couette flow to be imposed between parallel plates separated by 50 to 100 micrometers. The shear cell is designed to be mounted on the positioning stage of an inverted microscope, enabling simultaneous visualization of the microscopic structure as a function of time.

Filament Thinning Rheometer. Custom-built device designed to impose a step-elongational-strain and monitor the midplane diameter. Elongational viscosity of complex fluids can be deduced from these measurements.

Other Major Equipment housed in the Anna Lab includes:

Nikon TE2000U Inverted Light Microscope with brightfield, fluorescence, polarization, DIC, and phase contrast modes.  A heating stage allows control of sample temperature between 5C and 100C.

Redlake/IDT XS4 high speed camera capable of capturing high speed grayscale images up to 50,000 frames per second.  This camera is typically mounted on the light microscope for high speed video microscopy.

Nikon Eclipse Ti-U Inverted Epifluorescence Microscope with brightfield, fluorescence, and phase contrast modes and controllable XY and Z translation stages, laser launch, and high NA objectives.  Two laser lines are installed: Coherent 488nm 20 mW DPSS diode laser and 632 nm 5 mW HeNe laser with associated filter cubes for fluorescence (FRAP).  Nikon NIS Elements software for image/data acquisition and control.

Phantom v9.1 high speed camera capable of capturing 1,000 frames/sec at full frame, 150,000 frames/sec at minimum frame size.  Multiple frame rate profiles and triggering capabilities allow for capture of processes at multiple timescales. This camera is typically mounted on the light microscope for high speed video microscopy.

Agiltron Raman R3000-II Portable Raman Spectrometer System (150 – 2400 cm-1 spectral range with 10 cm-1 spectral resolution)

SI Photonics Model 440 research grade UV-visible spectrophotometer (190 -980 nm) with C-mount fiber optic adapter to couple spectrophotometer to microscope and stainless steel flow cell with user selectable pathlength.

Soft Lithography Fabrication Capabilities including a Harrick Scientific Plasma Cleaner, and a Thinky Mixer

In addition to our own laboratories, we also have access to several shared facilities for fabrication and characterization.  These include:

The PPG Industries Colloids Polymers and Surfaces Laboratory

The CMU Microelectromechanical Systems Lab

The CMU Nanofabrication Facility

SAXS Facility