Test-Model and Quantitative RDDS Criterion Index Which Are Applied to Estimate Antimicrobic Potential of Nanomaterials Used for Water Purification and Treatment: Substantiation and Metrologic Assessment

Abstract

To reduce population health risks which occur when people consume drinking water from centralized water supply systems is a vital medical-biologic and technical problem. It can be sold, among other things, via development and application of new materials for water purification and treatment. Some natural and artificial nanomaterials have antimicrobic properties as they can eliminate microorganisms of various taxonomy (bacteria, yeastlike and mold fungi) and bacterial biofilms. However, certain results which were obtained when antimicrobic potential of nanomaterials was estimated are controversial; they are frequently only qualitative or semi-quantitative due to absence of a standard test protocol and well-grounded criterial assessment apparatus. So, the goal of this paper was to give methodological grounds and to create a unified and standardized test-model; to optimize parameters of a procedure and to substantiate a system of criteria applied for quantitative assessment of antimicrobic activity which is characteristic for nanomaterials applied for water purification and treatment. The research was performed on the following objects: samples of nanomaterials based on titanium dioxide which were applied for water purification and treatment. The authors have substantiated a test-model, suggested a criterion index R DDS , made up a standard test protocol for quantitative assessment of antimicrobic potential possessed by nanomaterials. The developed technology has been tested on samples of nanomaterials based on titanium dioxide. We have calculated and assessed metrological parameters of the procedure (repeatability standard deviation and repeatability limit) which conform to the requirements existing for similar procedures when confidence probability is assumed to be equal to 95 %; such requirements are fixed by the ISO (International Standardization Organization) and correspond to the GLP (Good Laboratory Practice) principles. The relevance of the test-model was validated; this relevance provides an objective quantitative assessment of antimicrobic potential which is possessed by materials applied for disinfection of water objects contaminated with microbiota of various taxonomy, as well as for control and prevention of bacterial infections which can be communicated with water.

Modification of nonwoven polymer materials for increasing of their filtration and antibacterial properties

“…pneumoniae have a negative charge, the same as that of hydroxyl radicals (HO −2 ) and superoxide anions (O −2 ). For St. aureus with a positive cell wall charge, the effect is insufficient 50–52 …”

“…For St. aureus with a positive cell wall charge, the effect is insufficient. [50][51][52] It has been shown that the modification of Aquaspun with OCT leads to almost complete suppression of the growth of E. coli, Kl. pneumoniae, and St. aureus with the formation of an inhibition zone of 0.25-0.5 mm for E. coli and Kl.…”