Analyte induced water adsorbability in gas phase biosensors: the influence of ethinylestradiol on the water binding protein capacity

Abstract

An ultra-sensitive gas phase biosensor/tracer/bio-sniffer is an emerging technology platform designed to provide real-time information on air-borne analytes, or those in liquids, through classical headspace analysis. The desired bio-sniffer measures gaseous 17α- ethinylestradiol (ETED) as frequency changes on a quartz crystal microbalance (QCM), which is a result of the interactions of liquid sample components in the headspace (ETED and water) with a biorecognition layer. The latter was constructed by immobilization of polyclonal antiserum against a phenolic A-ring of estrogenic receptors through protein A. The QCM response exhibited stretched exponential kinetics of negative frequency shifts with reversible and "irreversible" components of mass uptake onto the sensor surface in static headspace conditions when exposed to water solutions of ETED over the sensor working range, from 10(-10) to 10(-17) g L(-1). It was shown that the variations in the QCM response characteristics are due to the change of the water-binding capacity of the sensing layer induced by protein transformations initiated by the binding of ETED molecules. This result is well correlated with the natural physiological function of estrogens in controlling the homeostasis of body fluids in living beings.

The effect of small addition of copper on the growth process, structure, surface charge and adsorption properties of ZnO films in the pyrolysis of dithiocarbamates

“…This effect of small doses has been observed many times in various physical, chemical and biological systems. [30][31][32][33] A similar effect was noted by the authors of the work, 34 where with an increase in the copper concentration during the synthesis of zinc oxide, the intensity of the diffraction peak of the dominant texture (002) first increased and then decreased.…”

Sample handling for electronic nose technology: State of the art and future trends

“…At the same time the effects of analyte induced water adsorbtion may be used for design and development of unique ultrasensitive approaches with detection limit up to 10 −17 g/L of potent xenobiotics (see 7.2, [51]). …”

“…To illustrate, it was shown that the variations in the QCM response are due to the change of water-binding capacity of the biorecognition layer induced by protein transformations initiated by the binding of ethinylestradiol molecules [51].…”

Adsorbate Induced Transformations of Ovalbumin Layers in Volatile Organic Solvents: QCM Study of a Potential Bio-Sniffer for Acute Toxicity Assays

“…However, modern chemistry is still unable to predict and synthesize chemical structures with precisely tuned chemical functionality. This explains the fact that an increasing number of researchers are testing the molecular biosystems of living organisms with their predetermined functionality as sensitive layers of sensors [1,2].…”

“…As with other albumins, OVA binds well to a wide variety of substances, including those that are poorly soluble in water; the adsorption capacity can reach more than 10% of the protein weight. Such features of albumins allow us to consider their coatings as promising sensitive layers in gaseous biosensors (so-called "bio-sniffers" [1,2,5,6]). In this work, we study the possibility for OVA layers deposited on different substrates (namely, silver, silver coated by buckminsterfullerene C 60 , and silver coated by copper phthalocyanine CuPc) to be a sensitive coating in QCM transducers to detect various analytes such as water, alcohols, acetone, cyclohexane, and benzene.…”