A simple, inexpensive membrane-based water sampling device for selective detection of specific analyte ions (pollutants) in the field of environmental monitoring.
Passive sampling refers to environmental sampling over an extended period of time, which may employ a sampling duration of just a few hours, or even up to a few weeks. This simple and low cost technology allows an inexpensive approach to keep up with the requirements of sampling a huge array of pollutants at many locations. It also enables determination of the average concentration of bio-available analytes over time. This is not possible with spot sampling of pollutants due to their ever-fluctuating concentrations in nature and/or episodic pollution events.
Passive sampling can also aid in the study of the uptake and accumulation of chemicals (e.g. metals, and organic pollutants) in organisms.
The presence of certain chemicals in the environment can have adverse effects on the organisms living in it. Sampling for specific hazardous materials in water provides a method to monitor, determine the origin of a problem and mitigate its ongoing occurrence.
Current sampling techniques to catch episodic pollution events are expensive. To identify a problem requires people to enter the drain, place an instrument and a camera into the monitoring area. This is resource and labour intensive.
The device uses a polymer inclusion membrane (PIM), these are a new type of liquid membranes, where a suitable extractant (carrier) is immobilized within the nanoporous structure of a plasticized thermoplastic base polymer. These membranes have shown great promise in the separation of various dissolved metals from waste solutions, which are of interest to the metals and mining industry, as it reduces or eliminates the use of expensive, highly flammable, volatile and often toxic solvents required for traditional solvent extraction based separation. The device enables identification of pollutants in water such as ammonia and heavy metals.
- Low cost to manufacture the device
- Simpler processing as the analyte can be determined directly in the internal solution without complex sample pretreatment operations such extraction, desorption or digestion
- Allows intermittent sampling which is not possible with current samplers
- Enables rapid field testing, compared to laboratory based testing required by current samplers
- It can be easily reused by simply replacing the internal solution.
PCT patent application PCT/AU2011/001571having priority date of 3rd December 2010.
Currently the devices are being trialled in the field for detection of ammonia and zinc
UoM Commercial is looking for partners to take the prototype device to market and/or provide the environmental testing services.
Bob Cattrall, Vincent Pettigrove, Cleopas Chan and Spas Kolev.
Download the Novel Membrane Based Passive Samplers flyer.