Instrumentation

Chemistry students at Wellesley are given the opportunity to work with sophisticated instruments both for laboratory courses and individual research.

The department boasts many state-of-the-art equipment that are carefully maintained by our instrumentation technician, Elaine Igo and our advanced instrumentation specialist, Jon Rose. General questions about all instruments should be directed to either Elaine (eigo@wellesley.edu, x3136) or Jon (jrose@wellesley.edu, x3016).


 

Calorimeters

Calorimetry is used to determine the heat released or absorbed in a chemical reaction. The calorimeters shown here can determine the heat of a solution reaction at constant (atmospheric) pressure. Our DSC and ITC calorimeters are used in our Chem. 232, 222, 221, and 328 classes.

Contact: Didem Vardar Ulu or Marilyn Turnbull

Circular Dichorism Spectrometer
A circular dichorism (CD) spectrometer measures the difference in adsorption of left- and right-handed light by a sample.  While CD can be used to monitor a variety of chiral chemical systems, its primary use at Wellesley is to monitor the secondary structure of proteins.  The technique is used to consider protein structure and stability in a variety of biochemistry courses (Chem 222, Bioc/Chem 223 and Bioc/Chem 340) as well as in many research labs.

Contact: Donald Elmore

Flash Chromatograph

Flash Chromatography is a rapid form of preparative column chromatography based on optimized pre-packed columns through which solvent is pumped at a high flow rate. It is a simple and economical approach to Preparative LC.

Contact: Dora Carrico-Moniz

Fluorometer

Fluoremeters (2) measure the fluorescence properties of samples. The instruments are used to study protein structure and folding in biochemistry classes (Chem 221, 222, and 328), and to investigate spectroscopic principles in physical chemistry classes (Chem 231, 232, and 333). They are also used by the Flynn lab to study drug release from hydrogels, by the Wolfson lab to measure the kinetics of enzyme reactions, and by the Elmore lab to characterize how antimicrobial peptides interact with lipid membranes and nucleic acids.

Contact: Don Elmore

FTIR-ATR

Fourier transform infrared spectrometers (2) are useful for the functional group analysis of typical organic compounds, and also more generally for any compounds where vibrational spectroscopy is anticipated to be helpful. A special feature is the attenuated total reflectance accessory, providing easy and rapid analysis of solids. The instruments are used heavily in organic chemistry classes (Chem 211 and 212), and also for research by nearly all investigators of organic materials. For instrument instructions, please click here.

Contact: Michael Hearn

Gas Chromatograph

Gas Chromatography (GC) is used to separate volatile components of a mixture so that they can be identified and quantified. A moving gas (the mobile phase) carries the sample across a stationary phase (the solid support found within a GC column). It is estimated that 10-20% of the known compounds can be analyzed by GC. Students use these gas chromatographs (2) extensively in Chem. 211.

Contact: Nick Doe

GC/MS

Gas chromatography-mass spectroscopy (GC-MS) is one of the so-called hyphenated analytical techniques. Gas chromatography separates the components of a mixture, and mass spectroscopy characterizes each of the components individually. It can be used to both qualitatively and quantitatively evaluate a solution containing a number of chemicals. Our two instruments are used in organic chemistry classes (Chem. 211 and 212) and by several members of the faculty in their research.

Contact: David Haines

HPLC

The high performance liquid chromatography (HPLC) system is used for the separation of molecules that use UV-VIS absorbance for detection. We have been using this instrument for the separation and analysis of peptide and nucleotide mixtures using reverse phase C18 chromatography. This instrument is used in biochemistry classes (Chem 221, 222, and 328).
For instrument instructions, please click here.

Contact: Elizabeth Oakes or Mona Hall

Low Energy Electron Diffraction

The LEED experiment uses a collimated beam of nearly monoenergetic low-energy electrons (typically in the range 20 - 200 eV) incident normally on the sample. Placed in an ultrahigh vacuum chamber, the sample itself must be a single crystal with a well-ordered surface structure in order to generate a back-scattered electron diffraction pattern. Students in Chemistry 333 reenact the classic experiment of Davisson and Germer as a dramatic confirmation of the wave nature of matter and determine the surface structure of a Molybdenum single crystal. The instrument is also used extensively in the Arumanaiyagam lab.

Contact: Chris Arumanaiyagam

MALDI-TOF Mass Spectrometer

Matrix-assisted laser desorption/ionization (MALDI) refers to a soft ionization technique used to analyze fragile biomolecules and large organic molecules. It is used with the time-of-flight (TOF) spectrometer, and hence the complex is referred to as the MALDI-TOF. The instrument is often used in our biochemistry labs, and is shared with the Biological Sciences department.

Contact: Elizabeth Oakes

NMR

Nuclear magnetic resonance (NMR) exploits the magnetic properties of certain nuclei. Many types of information can be obtained from an NMR spectrum. Much like using infrared spectroscopy to identify functional groups, analysis of a 1D NMR spectrum provides information on the number and type of chemical entities in a molecule. Our 300MHz NMR is used in our Chem. 212 class. Our 400MHz NMR is used by several faculty members for their research using the MRI probe. 

Contact: Nancy Kolodny

Polarimeter

A polarimeter is used to measure the polarization of light. This instrument is used with the refractometer in our Chem. 211 course to help students identify their unknown compounds.

Refractometers

A refractometer is an optical instrument that is used to determine the refractive index of a substance. It can be used to help determine the identity of an unknown liquid based on its refractive index, to assess the purity of a particular liquid, or to determine the concentration of a substance dissolved in a solution. The refractometers (3) are used in the Chem. 211 course to help identify unknown organic liquids.

Contact: Nick Doe

Spectrophotometer

A spectrophotometer consists of two instruments, namely a spectrometer for producing light of any selected color (wavelength), and a photometer for measuring the intensity of light. The amount of light passing through the tube is measured by the photometer. The photometer delivers a voltage signal to a display device, normally a galvanometer. The signal changes as the amount of light absorbed by the liquid changes. Our spectrophotometers (5) are used by several of our chemistry courses.

Contact: Nolan Flynn or Mona Hall

 

Related

Contact Us

Department of Chemistry
Science Center
Wellesley College
106 Central Street
Wellesley, MA 02481

 

Adele Wolfson
Department Chair
awolfson@wellesley.edu
Tel: 781.283.3106
Fax: 781.283.3642

 

Deborah Nickerson
Administrative Assistant
dnickers@wellesley.edu
Tel: 781.283.3114
Fax: 781.283.3642

 

Karen Blake
Administrative Assistant
kblake@wellesley.edu
Tel: 781.283.3022
Fax: 781.283.3642