TY - JOUR
T1 - Nano-enabled sensing of per-/poly-fluoroalkyl substances (PFAS) from aqueous systems – A review
AU - Garg, Shafali
AU - Kumar, Pankaj
AU - Greene, George W.
AU - Mishra, Vandana
AU - Avisar, Dror
AU - Sharma, Radhey Shyam
AU - Dumée, Ludovic F.
N1 - Funding Information:
A/Prof. Ludovic F. DUMEE acknowledges the Australian Research Council ( ARC ) for his Discovery Early Career Research Award (DECRA) 2018. LFD acknowledges the support from Khalifa University through project RC2-2019-007. The authors acknowledge the support of Deakin University and the Micro-Nano group (Prof. Lingxue Kong). The support extended by the Ministry of Education , Government of India to the Delhi School of Climate Change & Sustainability, Institute of Eminence, University of Delhi is duly acknowledged by RSS and VM. RSS acknowledges the FRP research grant (Ref. No./IoE/2021/12/FRP of October 29, 2021). SG and PK extend thanks to University Grants Commission for Junior Research Fellowship and the University of Delhi .
Funding Information:
Nucleation of a gas bubble through super-saturation of dissolved gas such as H2 was carried out to generate heat, which in turn can be utilized for producing an electrical impulse employed for sensing (Jones et al., 1999). The high surface area of the surfactant (PFOS/PFOA) analyte was exploited for overcoming the energy barrier of the gas-liquid interface, thus transducing the change in the super-saturation level resulting in the generation of an EC signal (Ranaweera et al., 2019). The reaction was self-sustained and energy-efficient due to the use of platinum nano-electrodes, which were used to catalytically generate H2 needed to support the nucleation reaction of the gas bubbles. Sensing efficiencies of 30 μg/L, 75 times more than the PL of 0.4 μg/L for PFOA and 80 μg/L, 400 times more than the PL of 0.2 μg/L for PFOS were achieved (Table 1, Entry 6). Additionally, the preconcentration of samples helped achieve 0.07 μg/L of LOD, which is equivalent to the lifetime health advisory for the joint PFOS and PFOA concentration in the drinking water (EPA, 2016). In another instance, a 1000-fold preconcentration of 10 PFAS was achieved using an H2 bubble. A Ni electrode was used to generate bubbles, where due to the high surface activity of PFAS, they spontaneously adsorb and aggregate. On reaching the surface, the bubbles burst but only a thin layer of liquid surrounding it was ejected into the atmosphere, whereas the major concentration of PFAS remains in the aerosol droplet, preconcentrating the samples by 0.0005–0.5 μg/L (Cao et al., 2019). However, this is a sole case of a PFAS preconcentration-based sensor in the gaseous phase and lack parallels to assess suitability.A/Prof. Ludovic F. DUMEE acknowledges the Australian Research Council (ARC) for his Discovery Early Career Research Award (DECRA) 2018. LFD acknowledges the support from Khalifa University through project RC2-2019-007. The authors acknowledge the support of Deakin University and the Micro-Nano group (Prof. Lingxue Kong). The support extended by the Ministry of Education, Government of India to the Delhi School of Climate Change & Sustainability, Institute of Eminence, University of Delhi is duly acknowledged by RSS and VM. RSS acknowledges the FRP research grant (Ref. No./IoE/2021/12/FRP of October 29, 2021). SG and PK extend thanks to University Grants Commission for Junior Research Fellowship and the University of Delhi.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/4/15
Y1 - 2022/4/15
N2 - Per-/poly-fluoroalkyl substances (PFAS) are an emerging class of environmental contaminants used as an additive across various commodity and fire-retardant products, for their unique thermo-chemical stability, and to alter their surface properties towards selective liquid repellence. These properties also make PFAS highly persistent and mobile across various environmental compartments, leading to bioaccumulation, and causing acute ecotoxicity at all trophic levels particularly to human populations, thus increasing the need for monitoring at their repositories or usage sites. In this review, current nano-enabled methods towards PFAS sensing and its monitoring in wastewater are critically discussed and benchmarked against conventional detection methods. The discussion correlates the materials’ properties to the sensitivity, responsiveness, and reproducibility of the sensing performance for nano-enabled sensors in currently explored electrochemical, spectrophotometric, colorimetric, optical, fluorometric, and biochemical with limits of detection of 1.02 × 10−6 μg/L, 2.8 μg/L, 1 μg/L, 0.13 μg/L, 6.0 × 10−5 μg/L, and 4.141 × 10−7 μg/L respectively. The cost-effectiveness of sensing platforms plays an important role in the on-site analysis success and upscalability of nano-enabled sensors. Environmental monitoring of PFAS is a step closer to PFAS remediation. Electrochemical and biosensing methods have proven to be the most reliable tools for future PFAS sensing endeavors with very promising detection limits in an aqueous matrix, short detection times, and ease of fabrication.
AB - Per-/poly-fluoroalkyl substances (PFAS) are an emerging class of environmental contaminants used as an additive across various commodity and fire-retardant products, for their unique thermo-chemical stability, and to alter their surface properties towards selective liquid repellence. These properties also make PFAS highly persistent and mobile across various environmental compartments, leading to bioaccumulation, and causing acute ecotoxicity at all trophic levels particularly to human populations, thus increasing the need for monitoring at their repositories or usage sites. In this review, current nano-enabled methods towards PFAS sensing and its monitoring in wastewater are critically discussed and benchmarked against conventional detection methods. The discussion correlates the materials’ properties to the sensitivity, responsiveness, and reproducibility of the sensing performance for nano-enabled sensors in currently explored electrochemical, spectrophotometric, colorimetric, optical, fluorometric, and biochemical with limits of detection of 1.02 × 10−6 μg/L, 2.8 μg/L, 1 μg/L, 0.13 μg/L, 6.0 × 10−5 μg/L, and 4.141 × 10−7 μg/L respectively. The cost-effectiveness of sensing platforms plays an important role in the on-site analysis success and upscalability of nano-enabled sensors. Environmental monitoring of PFAS is a step closer to PFAS remediation. Electrochemical and biosensing methods have proven to be the most reliable tools for future PFAS sensing endeavors with very promising detection limits in an aqueous matrix, short detection times, and ease of fabrication.
KW - Detection
KW - Economics
KW - Nanomaterials
KW - PFOA
KW - PFOS
KW - Sensing
KW - Water monitoring
UR - https://www.scopus.com/pages/publications/85123942807
U2 - 10.1016/j.jenvman.2022.114655
DO - 10.1016/j.jenvman.2022.114655
M3 - Review article
C2 - 35131704
AN - SCOPUS:85123942807
SN - 0301-4797
VL - 308
JO - Journal of Environmental Management
JF - Journal of Environmental Management
M1 - 114655
ER -
