A Biophysics Core  has been established at the James Graham Brown Cancer Center where researchers can measure functional properties of their purified systems using a variety of biophysical methods including calorimetry, optical spectroscopy such as fluorescence and circular dichroism, rapid reaction kinetics and hydrodynamic techniques.

Dr. J. Brad Chaires, director of the Biophysics Core Facility, has more than 30 years experience in biophysics, with particular recent emphasis on biological microcalorimetry. Dr. Nichola Garbett is the facility manager and can be reached at

Instruments available include:


MicroCal VP-ITC Calorimeter

MicroCal VP-DSC Calorimeter with Pressure Perturbation Accessory

MicroCal VP-Capillary DSC

Calorimetric Sciences Corporation Nano II DSC

These instruments measure the heats of reactions directly, and may be used to determine complete thermodynamic profiles (free energy, enthalpy, entropy, heat capacity changes, compressibility) for binding interactions and conformational transitions. Such information may be used to define the molecular forces important for the reaction under study. The VP-Capillary DSC allows for high-throughput thermodynamic measurements. The instrument features a robotic liquid handling system that allows for 24 samples to be run per day. Only 13 such instruments are available in academic environments worldwide.

Electronic Spectroscopy

Jasco J-810 Spectropolarimeter-Circular Dichroism (equipped with an auto-titrator, Peltier temperature control, and simultaneous fluorescence detection)

Jasco FP-6500 spectrofluorometer with accessories

Jasco V-550 double beam spectrophotometer with accessories

On-line Instrument Systems, Inc. UV/Vis Diode Array Workstation.

These instruments allow measurements of absorbance, fluorescence, and optical activity of macromolecules and drugs that interact with the given target. Each spectroscopy provides a unique window into the reaction. These spectroscopies may be used to obtain thermodynamic profiles for binding reactions, conformational transitions, and denaturation reactions. Circular dichroism provides low-resolution structural information about protein and nucleic acid secondary structure, and is an invaluable adjunct to higher resolution NMR and crystallographic methods. They also can be used for early screening of new protein quality, as well as for drug-targeted binding screens.

Rapid Kinetics

On-line Instrument Systems, Inc., Rapid Scanning Stopped-Flow Spectrophotometer System

This instrument allows the rates of reactions to be measure in the millisecond and beyond time scale. Reaction kinetics may be used to infer the detailed reaction mechanism for a binding interaction or conformational transition.


Beckman-Coulter XL-A Analytical Ultracentrifuge

The analytical ultracentrifuge is a method firmly grounded in fundamental physical principles. The instrument may be used to determine molecular weights directly and unambiguously by sedimentation equilibrium. The sedimentation velocity method allows determination of hydrodynamic shapes and molecular dimensions, an invaluable adjunct to higher resolution NMR and crystallographic methods. Available modern software allows analytical ultracentrifugation to be used to study the thermodynamics of macromolecular interactions. This instrument was purchased with funds from an NCRR SIG.

Wyatt Dawn Heleos light-scattering detector (and differential refractometer).

The multi angle static light scattering complements the analytical ultracentrifuge and can provide direct determination of molecular weights of assemblies and the radius of gyration. Collectively the facility provides a very diverse set of possibilities for characterizing systems of interest. The availability of the diversity of possible signals makes it possible to develop screening for interactions for almost any class of compounds.