Ultrasensitive environmental assessment of xeno-estrogens in water samples using label-free graphene immunosensors

Abstract

There is a growing interest in the possible environmental health impact posed by endocrine-disrupting chemicals (EDCs). A challenge to the field of endocrine disruption is that these substances are diverse and may not appear to share any structural similarity other than usually being low molecular mass (<1000 Da) compounds. Here we demonstrate the effectiveness of sensor device for the detection of low molecular weight, poorly water soluble, estrogenic compounds E1, E2 and EE2, fabricated by electropolymerization over graphene screen printed electrode (SPE). The PANI/Gr-SPE-devices displayed linear responses to estrogenic substances, in EIS assays, from 0.0975 ng/L to 200 ng/L in water samples, with a detection limit of 0.043 pg/L for E1, 0.19 ng/L for E2 and 0.070 pg/L for EE2 which is lower than other current biosensing techniques. This portable, disposable immunosensor offers a solution for immediate measurement at sample collection sites, due to its excellent sensitivity and selectivity when testing water samples obtained directly from rivers and waste water treatment facilities. The simple screen printing production method will enable the low cost, high volume production required for this type of environmental analysis.

Endocrine Disruptors in Water and Their Effects on the Reproductive System

“…The most prevalent estrogens found in the environment are estrone, 17β-estradiol, 17α-estradiol, and estriol. These estrogens are naturally produced by humans and non-human animals [267]. Natural phytoestrogens from plants are also released in the environment [268].…”

Endocrine disrupting chemicals in water and recent advances on their detection using electrochemical biosensors

“…ERK signaling pathways are closely related to many cellular activities such as division, differentiation, apoptosis, and carcinogenesis. 32 Long chain alkylphenols are often applied as non-ionic surfactants, which are the main ingredient in detergents or cleaners.…”

Gas Fermentation Expands the Scope of a Process Network for Material Conversion

“…For LGS fermentation, different research groups have worked on methods that increase the availability of the gaseous substrates for cultivated microorganisms. The effects of increasing substrate availability have been tested in serum bottles by either increasing the total headspace pressure or varying the partial pressure of single gas components [144][145][146][147]. Their results indicated that the gas composition in syngas fermentation plays a key role in process design.…”