Electroanalytical determination of Bisphenol A: Investigation of electrode surface fouling using various carbon materials

The plastic monomer and plasticizer bisphenol A (BPA) is one of the highest volume chemicals produced worldwide. BPA is used in the production of polycarbonate plastics and epoxy resins used in many consumer products. Here, we have outlined studies that address the levels of BPA in human tissues and fluids. We have reviewed the few epidemiological studies available that explore biological markers of BPA exposure and human health outcomes. We have examined several studies of levels of BPA released from consumer products as well as the levels measured in wastewater, drinking water, air and dust. Lastly, we have reviewed acute metabolic studies and the information available about BPA metabolism in animal models. The reported levels of BPA in human fluids are higher than the BPA concentrations reported to stimulate molecular endpoints in vitro and appear to be within an order of magnitude of the levels needed to induce effects in animal models. Show more

Bisphenol A (CAS 85-05-7) may be released into the environment through its use and handling, and permitted discharges. BPA is moderately soluble (120 to 300 mg/L at pH 7), may adsorb to sediment (Koc 314 to 1524), has low volatility, and is not persistent based on its rapid biodegradation in acclimated wastewater treatment plants and receiving waters (half-lives 2.5 to 4 days). BPA is "slightly to moderately" toxic (algal EC50 of 1000 micrograms/L) and has low potential for bioaccumulation in aquatic organisms (BCFs 5 to 68). The chronic NOEC for Daphnia magna is > 3146 micrograms/L. Surface water concentrations are at least one to several orders of magnitude lower than chronic effects, with most levels nondetected. Show more

Novel nanomaterials for bioassay applications represent a rapidly progressing field of nanotechnology and nanobiotechnology. Here, we present an exploration of single-walled carbon nanotubes as a platform for investigating surface-protein and protein-protein binding and developing highly specific electronic biomolecule detectors. Nonspecific binding on nanotubes, a phenomenon found with a wide range of proteins, is overcome by immobilization of polyethylene oxide chains. A general approach is then advanced to enable the selective recognition and binding of target proteins by conjugation of their specific receptors to polyethylene oxide-functionalized nanotubes. This scheme, combined with the sensitivity of nanotube electronic devices, enables highly specific electronic sensors for detecting clinically important biomolecules such as antibodies associated with human autoimmune diseases. Show more