Development of a passive sampler based on a polymer inclusion membrane for total ammonia monitoring in freshwaters

Abstract

A passive sampler for determining the time-weighted average total ammonia (i.e. molecular ammonia and the ammonium cation) concentration (C TWA) in freshwaters, which incorporated a polymer inclusion membrane (PIM) as a semi-permeable barrier separating the aqueous source solution from the receiving solution (i.e. 0.8 mol L(-1) HCl), was developed for the first time. The PIM was composed of dinonylnaphthalene sulfonic acid (DNNS) as a carrier, poly (vinyl chloride) (PVC) as a base polymer and 1-tetradecanol as a modifier. Its optimal composition was found to be 35 wt% commercial DNNS, 55 wt% PVC and 10 wt% 1-tetradecanol. The effect of environmental variables such as the water matrix, pH and temperature were also studied using synthetic freshwaters. The passive sampler was calibrated under laboratory conditions using synthetic freshwaters and exhibited a linear response within the concentration range 0.59-2.8 mg L(-1) NH4(+) (0.46-2.1 mg N L(-1)) at 20 °C. The performance of the sampler was further investigated under field conditions over 7 days. A strong correlation between spot sampling and passive sampling was achieved, thus providing a proof-of-concept for the passive sampler for reliably measuring the C(TWA) of total ammonia in freshwaters, which can be used as an indicator in tracking sources of faecal contamination in stormwater drains.

Passive Sampling of SARS-CoV-2 for Wastewater Surveillance

“… 19 − 21 This interaction could include the association of a pollutant with a particular medium or substance 19 or induce a chemical reaction within the device. 20 At the end of the deployment, the passive sampler is analyzed through visual inspection or via advanced laboratory analytical methods. A notable advantage of passive sampling in water systems is that the deployment is easy (i.e., no specialized skills required), rapid, and usually does not require confined space entry permits.…”

A novel passive sampling approach for SARS-CoV-2 in wastewater in a Canadian province with low prevalence of COVID-19

“…21,22 A passive sampling approach provides a cost effective and relatively easy option to grab and composite sampling. This approach involves the use of a passive sampling device which is deployed at a location in the sewershed for a predetermined period, and contaminants in the wastewater are allowed to interact with an adsorbent material housed inside the device, 23,24 which results in the concentration of the virus. A passive sampling technique commonly referred to as the "Moore swab" has been previously used to extract enteric pathogens from cotton gauze in water.…”

The Use of a Polymer Inclusion Membrane for Arsenate Determination in Groundwater

“…These membranes are transparent, flexible and stable, and have been used in many applications such as sensing, both ion-selective electrodes (ISE) and optodes, sample pre-treatment (separation and pre-concentration), and electro-driven extraction. PIMs have also been used as passive samplers deploying the membrane device for a 7-day period without reporting any drawback due to membrane fouling [3][4][5]. With the proper selection of the carrier, these membranes can effectively transport different species, such as inorganic pollutants [5], organic compounds [6] and metallic species [7].…”