Nanobubble clusters of dissolved gas in aqueous solutions of electrolyte. I. Experimental proof

Abstract

Results of experiments with dynamic light scattering, phase microscopy, and polarimetric scatterometry allow us to claim that long-living gas nanobubbles and the clusters composed of such nanobubbles are generated spontaneously in an aqueous solution of salt, saturated with dissolved gas (say, atmospheric air). The characteristic sizes of both nanobubbles and their clusters are found by solving the inverse problem of optical wave scattering in ionic solutions. These experimental results develop our earlier study reported by Bunkin et al. [J. Chem. Phys. 130, 134308 (2009)] and can be treated as evidence for the special role of ions in the generation and stabilization of gas nanobubbles.

Particle Formation and Aggregation of a Therapeutic Protein in Nanobubble Suspensions

“…10, 14, 15 Consistent with previous reports, 7, 14 our zeta potential results confirmed that nanobubbles are negatively charged. Following reconstitution with rhIL-1ra the magnitude and sign of the zeta potentials in this system were dependent on the net charge on rhIL-1ra molecules, as controlled by altering buffer pH.…”

“…6 It has been proposed that nanobubble stability may be dependent on the selective adsorption of anions at the nanobubble interface. 10, 14, 15 At the nanobubble scale, ions adsorbed to the nanobubble interface could be in close enough proximity to result in repulsive forces strong enough to balance the compressive force from surface tension. The balance of these two forces would be expected to result in a nanobubble with a stable diameter where the dissolution of gas from the bubble would be minimized.…”

Possible Further Evidence for the Thixotropic Phenomenon of Water

“…The authors interpreted the experimental data by bubston clusters composed of polydisperse air bubbles having effective radii of 70-90 nm. Experiments with dynamic light scattering, phase microscopy and polarimetric scatterometry additionally indicated that long-lived gas nanobubbles and clusters composed of such nanobubbles are generated spontaneously in an aqueous solution of salt saturated with dissolved gas [96]. According to Pollack's [97] embryonic bubble concept in water next to nucleators, like hydrophilic surfaces or some solutes, EZ grow layer by layer and also laterally.…”

Ion-Specific and Thermal Effects in the Stabilization of the Gas Nanobubble Phase in Bulk Aqueous Electrolyte Solutions

“…41 The methodology of these experiments is based upon laser phase microscopy in conjunction with dynamic light scattering and measuring the angular 5 dependence of the scattering matrix elements. The operating principle of the phase microscope is described in detail in ref 42. The main advantage of such a device is that it combines a conventional far-field microscope with a laser interferometer working at a wavelength of 400 nm.…”