Offline Instrumentation


Organic Carbon/Elemental Carbon/Water Soluble Organic Carbon (OC/EC/WSOC)
OC/EC/WSOC values are important parameters for ambient particles. We use two different protocols for OC/EC determination depending on the requirements. One is the EUSAAR 2 protocol and the other is a modified version of VDI 2465 Part 2 protocol. WSOC values are determined using a Shimadzu TOC anlayser.

Capillary Electrophoresis with Ultraviolet Detector (CE-UV)
CE-UV is used to determine some inorganic anions and carboxylic and di-carboxylic acids smaller than C5.

High Performance Anion Exchange Chromatography Pulsed Amperometric Detection (HPAEC-PAD)
This instrument is dedicated to the routine determination of atmospheric sugars and sugar alcohols that originate from biomass burning (levoglucosan, mannosan and galactosan) and biogenic activity (arabitol, mannitol, glucose, mannose etc.).

Capillary Electrophoresis coupled with electrospray ionization Mass Spectrometry (CE/MS)
CE/MS is used for the determination of particle phase carboxylic acids and dicarboxylic acids that are greater than C5.

Liquid Chromatography coupled with electrospray ionization Mass Spectroscopy (LC/MS)
LC/MS is used for the determination of a wide variety of organic compounds in both the gas and particle phases. These compounds include carbonyl compounds (gas-phase), carboxylic acids, nitrophenols and organosulfates (particle phase). Prior to LC/MS analysis, carbonyl compounds are derivatised with 2,4-dinitrophenylhydrazine (DNPH) either in-situ or ex-situ depending on the sampling requirement.

Gas Chromatography-Mass Spectrometry (GC/MS)
GC/MS instruments are used to determine gas-phase VOCs, and particle phase PAHs, alkanes and hopanes. We use a Tenax TA cartridge and a thermal desorption unit as the sampler and injector for the former purpose, and filter/impactor samples and Curie Point Pyrolyzer for the latter purpose. In addition to them, we use silylation and alkylation derivatisation procedures to obtain structural information of unknown compounds.

Total Reflection X-Ray Fluorescence (TXRF) is a element specific technique that can be used for ultra-trace metal analysis of particles or impurities on smooth surfaces. We employ TXRF for trace metal analysis in fine and coarse mode Saharan dust, marine and continental aerosol particles.