Analytical Services Laboratory (Engineering North)

High-performance liquid chromatography (sometimes referred to as high-pressure liquid chromatography), HPLC, is a chromatographic technique used to separate a mixture of compounds in analytical chemistry and biochemistry with the purpose of identifying, quantifying or purifying the individual components of the mixture.

The HPLC in our analytical lab is equipped with photo diode array (pda) detector. There are Fluorescence and conductivity detectors also available for this instrument. The pda detector can be used for 2D and 3D data collection with testing wavelength in the range of 190 to 800nm. The fluorescence detector can be used to analyse non-ionic molecules which are strongly conjugated and have rigid structures. The conductivity detector detects the ability of analyte to carry a charge, such as inorganic anions and cations. 

HPLC Size Exclusion Chromatography (SEC) coupled Multi Angle Light Scattering (MALS) detector aim at separating macromolecules based on their physical properties and provide absolute accurate distributions of molar mass and size (root mean square radius rg) of macromolecules and nanoparticles in solution at every point of the eluting sample. The DAWN HELEOS II MALS incorporates detectors at 18 angles to determine molar masses from 200Da to 1GDa and radii from 10-500nm.

The Optilab T-rEX (refractometer with EXtended range) differential Refractive Index (dRI) detector serves as accurate and versatile concentration detector in all types of solvents. dRI is part of standard instrumentation for a variety of macromolecular characterization techniques including standard chromatography, SEC-MALS.

• Study protein structure – shape and mass, and protein quality and characterization.
• Characterize protein: oligomerization/aggregation, protein shape, changes in protein mass or shape caused by protein/ligand interaction, modification, or by environmental conditions.
• Used in protein, biopolymer and synthetic polymer characterizations.

Ultraviolet-visible Spectrophotometer (UV-vis) refers to absorption spectroscopy in the UV-vis spectral regions.  Many molecules absorb ultraviolet or visible light. The absorbance is directly proportional to the path length and the concentration of the absorbing species according to Beer's Law.  Thus, for a fixed path length, UV-vis can be used to determine the amount of a compound known to be present in the sample. 

The Shimadzu 2700 instrument analyses liquid samples. The solvents used are often water for water-soluble compounds, or ethanol for organic-soluble compounds. UV-vis can be used for the quantitative determination of different analytes, such as transition metal ions, highly conjugated organic compounds, and biological macromolecules. 

FTIR (Fourier Transform Infrared Spectroscopy) studies the effect of interaction between a sample and radiated energy in the IR range, and this effect is evaluated by measurement of the absorption/transmission of various IR frequencies by a sample situated in the path of an IR beam. When a beam of IR radiation is passed through a sample, the radiation can be either absorbed or transmitted, depending on its frequency and the structure of the molecules in the sample. IR radiation excites certain molecular groups, producing vibrations from the excited state at fixed wavelengths. The absorption of energy occurs at frequencies corresponding to the molecular mode of vibration of the corresponding molecule or chemical group. As different functional groups absorb characteristic frequencies of IR radiation, the technique is used in sample identification and investigation of molecular structures. Samples for the FTIR analysis on the Nicolet iS50 include solids, liquids, powders, pastes and films - all in a matter of minutes.

The atomic absorption spectrophotometer (AAS) is used as an analytical equipment for inorganic elemental analysis. It is used for the quantitative determination of chemical elements employing the absorption of optical radiation (light) by free atoms in the gaseous state. The AAS is used for determining the concentration of a particular element (the analyte) in a sample to be analysed. It provides the highest level of sensitivity for trace-level analysis (0.1ppm) in a liquid sample. AAS can be used to determine over 70 different elements in solution or directly in solid samples.