Water immobilization by glass microspheres affects biological activity

Abstract

We recently reported that the water holding capacity of myofibrillar protein hydrogels could be increased upon addition of small amounts of microparticles, particularly glass microspheres. Glass microspheres were found to decrease the spin-spin relaxation time (T2) of water protons in the gels, which was interpreted as enhanced water binding by the glass. We were thus interested in determining whether the observed effects on water proton relaxation were a direct consequence of water-glass interactions. Here we show how glass microspheres reduce the mobility of pure water, reflected in large decreases in the T2 of water protons, decreases in the self-diffusion coefficient of water molecules, a lower water activity, and strengthening of O-H bonds. Even though glass is considered an inert material, glass microspheres were shown to inhibit the growth of human embryonic kidney cells, and stimulate or inhibit the growth of leukemia and monocytic lymphoma cells in vitro, depending on dose and time. The germination of alfalfa seeds and the growth of E.coli cells were also inhibited upon exposure to glass microspheres. This work indicates that the properties and behavior of materials, even ones considered inert, can be affected by their size. These observations suggest possible toxicological consequences of exposure to microparticles, but also open us possibilities to affect cellular/organism function via modulation of macromolecular hydration.

Effects of microplastic and microglass particles on soil microbial community structure in an arable soil (Chernozem)

“…4). Based on the results by Marangoni et al (2018) is highly likely, that protozoa respond in a similar way to the presence of microglass like Escherichia coli.…”

“…hydrophilic surface groups (Schmidt et al, 2015) whereby microglass has a hydrophilic surface. A study by Marangoni et al (2018) showed, that glass microspheres (4 µm, 7-10 µm and 30-50 µm; micoglass addition of 1-5% v/v) reduced the mobility of water reflected in a large decrease of the spin-spin relaxation time of water protons, decreases in the self-diffusion coefficient of water molecules, a lower water activity, and strengthening of O-H bonds. The study further showed that glass microspheres have an inhibiting effect on Escherichia coli growth and the germination of Medicago sativa seeds.…”

Insights into the Interaction between Immobilized Biocatalysts and Metal–Organic Frameworks: A Case Study of PCN-333

“…Solid-state NMR has been proven to be a powerful tool to investigate the molecular dynamics in a variety of materials by applying relaxation or diffusion spectroscopy. 61 − 63 In this work, in order to understand the structural flexibility of the framework, the 1 H spin–lattice relaxation ( 1 H T 1 ) was measured by applying the inversion–recovery pulse sequence. For 1 H T 1 analysis, as the magnetization of 1 H nuclei can rapidly diffuse throughout the entire spin network of the solid, a relatively uniform T 1 value for all protons in the material is expected.…”

For Whom a Puddle Is the Sea? Adsorption of Organic Guests on Hydrated MCM-41 Silica

“…This effect has different consequences. A significant lowering of the liquid–solid − and solid–liquid − transition temperatures, varying physical and biological properties, − and a stabilization of thermodynamically unstable systems − are among them. All the molecules studied in this work did spread over the surface.…”