Light Scattering in Research and Quality Control of Deuterium Depleted Water for Pharmaceutical Application

Abstract

Objective: Development of a methodology for measuring the deuterium content in water for pharmaceutical purposes by laser light scattering based on ideas about the cluster structure of water.
 Methods: Samples of industrially manufactured drinking water from different manufacturers with varying deuterium content from 10 ppm to 115 ppm. For the titration of laboratory samples of deuterium depleted water in increments of 5 ppm the following reagents were used: Water, deuterium-depleted (≤1 ppm (D2O, Aldrich, USA); Deuterium oxide/Heavy water/Water-d2 (99.9 atom % D, Aldrich, USA); water Milli-Q (specific resistance 18.2 µS·sm at 25 оС, ТОС ≤ 5 ppb, Merck Millipore). The determination of deuterium content in samples of industrially manufactured water and water obtained in a laboratory manner was carried out by the method of low-angle laser light scattering (LALLS) at the Mastersizer (Malvern Instruments) analyzer and using a working measuring tool–laser dispersion meter/MDL («Cluster-1», Russia/Ukraine). The statistical methods–packages OriginPro®9.
 Results: It was found that the content of isotopologies in water leads to physicochemical water’s properties changes and morphology changes of giant heterogeneous clusters (GHC). The results of low-angle laser light scattering (LALLS) in the water samples under investigation showed the dependence of the water GHC "dispersibility" expressed in the differentiation of curves of the volume size distribution ("size spectra"), the volume concentration, w%, the laser obscuration values (I ‒I0) as the function of the water isotopic composition variations. The laser diffraction method results correlate with two-dimensional (2D) multi-descriptor mathematical analysis.
 Conclusion: When identifying deuterium depleted water, it should be considered not only the indicators that determine its pharmacopoeial quality, but also the D/H ratio, because even small changes in the natural isotopic composition of water lead to significant biological effects. Our proposed approach using laser diffraction in combination with mathematical apparatus of (2D) multi-descriptor laser scattering analysis makes possible the exact calculation of individual signs of deuterium depleted water as the pharmaceutical object of study.

The new two-dimensional light scattering method for recognition of pharmaceutical enantiomers

“…, and r (Koldina et al, 2019). The measurement results made it possible to reveal differences in the nature of the studied samples.…”

“…The method has successfully proven itself in assessing the quality of liquid dosage forms: suspensions, emulsions, tinctures, and determining the authenticity of medicinal and table waters without opening the package, as well as the stability of cluster structures in waters of different isotopic composition (Bunkin et al, 2018;Goncharuk et al, 2011;Karpov et al, 2011;Koldina et al, 2019;Ul'yantsev et al, 2009). Reliability of measurements, nondestructive nature, low cost, simplicity of calibration procedures, and short measurement times are important advantages of the method in the analysis of pharmaceutical substances.…”

Application of Mathematical Modeling and Physico-Chemical Analysis Methods in the Prediction of Biological Activity and Quality Control of Gossypol Derivatives

“…Kinetic dissolution of the GAA in ethanol was carried out by the method of low-angle laser light scattering (LALLS) [20] on Mastersizer 3600 optical set-up (Malvern Panalytical, United Kingdom) (fig. 3).…”

Preparation, Characterization and Studies of Physicochemical and Biological Properties of Drugs Coating Lactose in Fluidized Beds

“…For the analysis of lowfrequency micro oscillations of drugs, a portable optical microscope was used and was connected to a personal computer USB-camera. The obtained interference patterns were mathematically processed with the help of three descriptors (criteria of difference), which reflect their degree of difference and allow estimating them quantitatively Vidan® software was used for data processing [35,36].…”