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BIOGRIP Node for Soil and Water Analysis fully operational
Author: E Els & Dr J Colling
Published: 13/04/2021

The BIOGRIP Node for Soil and Water Analysis at Stellenbosch University is now fully operational. The node focuses on enabling the interdisciplinary study of the chemical, physical, geological and biological processes that influence the environment. The facility provides researchers and post-graduate students with technical support and access to state-of-the-art equipment to perform research projects. Clients from higher education institutes and the private and public sector can also submit samples for routine analysis.

The node offers a wide range of instruments and services including a Metrohm Ion Chromatography (IC) instrument (Fig 1) for the analysis of various ions. This includes for example the quantification of anions (Cl, F, NO2, NO3, PO4, SO4, Br) and cations (Li, Ca, K, Na Mg, NH4,) in aqueous (rain, surface, ground, municipal and effluent) samples.  Currently, this service is primarily used to measure the ions in surface (rivers and dams) and ground (borehole) water and methods are also being developed to quantify ions in soil extracts. The results and information obtained can be used to evaluate the safety of water for drinking purposes and to study how the levels of ions are changing over seasons and time.


Figure 1: The Ion Chromatography instrument includes a Metrohm 858 Autosampler with 127 positions for sample introduction. It also offers options for inline auto dilution and ultrafiltration of samples prior to analysis and quantification of ions.

The node also houses a Los Gatos Research (LGR) liquid water isotope analyser (LWIA), which can measure the δ18O, δ17O and δ2H stable isotopes of water in liquid and discrete vapour samples (Fig 2).   Analysis of stable isotopes is being used to study the movement of water above and below the earth's surface as part of the water cycle. This information can be used to determine flow paths of groundwater and provide insight into the possible hydrological processes such as water recharge, mixing and leaching. Since water bodies at different stages of the hydrological cycle have characteristic O/H signatures, the stable isotopes can be used as tracer elements to study specific information about the water cycle.


Figure 2: The Triple Liquid-Water Isotope Analyzer (T-LWIA) equipment uses High Resolution Laser Absorption Spectroscopy technique and simultaneously measures stable isotopes ratios, such as, Deuterium/Hydrogen (2H/H), 17Oxygen/16Oxygen (17O/16O) and 18Oxygen/16Oxygen (18O/16O) in liquid water samples.

An IDEXX system, which can be used to detect the presence/absence of micro-organisms including Faecal Coliforms, Total Coliforms or Eschericia coli is also available (Fig 3).  The IDEXX kits can also be used to quantify these micro-organisms in samples according to MPN (Most Probable Number) as CFU/ 100 ml. 


Figure 3: IDEXX system for analysis of micro-organisms in a variety of samples such as ground (borehole), surface (rivers, drinking water, rainwater) and seawater.

A pH and EC meter is also available. Several new instruments will become available during the course of the next couple of months.  This includes a Vario Total Organic Carbon (TOC) cube from Elementar, which can be used for the quantification of total organic carbon (TOC), Total carbon (TC), Total inorganic carbon (TIC) and Total biological nitrogen (TNb). This instrument will enable the analysis of liquid and solid samples ranging from ultrapure water, industrial wastewater, concentrated salt solutions and/or solids.  A BluevisionTM discrete analyzer from Skalar is also being added. This automated UV spectrophotometer can be used for the quantification of various parameters including alkalinity, total hardness, colour and ion content (Sulfate, Nitrite, Nitrate+Nitrite, Ammonia, Ortho-Phosphate, Silicate) of aqueous samples.  There are a few more instruments, which will also become available, but more information about these will become available later.

The Facility is managed by Dr Janing Colling who has a PhD in Biotechnology from Stellenbosch University. She has recently been joined by Ms Volante Moonsamy. Ms Moonsamy has a BSc in Industrial and Applied Biotechnology and a BSc Honours and MSc in Microbiology. The facility is situated in the Paul Sauer Building in Bosman street on the Stellenbosch University campus. For more information or to contact the facility, please visit www.sun.ac.za/caf or click here.