Water spectral pattern as holistic marker for water quality monitoring.

Online water quality monitoring technologies have been improving continuously. At the moment, water quality is defined by the respective range of few chosen parameters. However, this strategy requires sampling and it cannot provide evaluation of the entire water molecular system including various solutes. As it is nearly impossible to monitor every single molecule dissolved in water, the objective of our research is to introduce a complimentary approach, a new concept for water screening by observing the water molecular system changes using aquaphotomics and Quality Control Chart method. This approach can continuously provide quick information about any qualitative change of water molecular arrangement without taking into account the reason of the alteration of quality. Different species and concentrations of solutes in aqueous systems structure the water solvent differently. Aquaphotomics investigates not the characteristic absorption bands of the solute in question, but the solution absorption at vibrational bands of water's covalent and hydrogen bonds that have been altered by the solute. The applicability of the proposed concept is evaluated by monitoring the water structural changes in different aqueous solutions such as acid, sugar, and salt solutions at millimolar concentration level and in ground water. The results show the potential of the proposed approach to use water spectral pattern monitoring as bio marker of water quality. Our successful results open a new venue in water quality monitoring by offering a quick and cost effective method for continuous screening of water molecular arrangement. Instead of the regular analysis of individual physical or chemical parameters, with our method - as a complementary tool - the structural changes of water molecular system used as a mirror reflecting even small disturbances in water can indicate the necessity of further detailed analysis by conventional methods.

Water revealed as molecular mirror when measuring low concentrations of sugar with near infrared light.

Near infrared spectroscopy is an overtone spectroscopy regarded as a quick and non-destructive method that provides analytical solutions for components that represent approximately 1% or more of the total mass of the investigated composite samples. Aquaphotomics offers the possibility for disentanglement of information remaining hidden in the spectra when conventional data evaluation methods are used, since this concept utilizes changes of the water structure induced by the measured solute as specific molecular vibrations at water bands. Here, near infrared technique and aquaphotomics are applied for non-destructive identification and quantification of mono- and di-saccharide solutes at 100-0.02 mM concentration that is accepted as unachievable with near infrared spectroscopy. The results presented in this study support the aquaphotomics' water molecular mirror concept that explores spectral changes related to water molecular rearrangements caused by minute changes of the solutes in the aqueous systems. The method provides quick and accurate alternative for classical analytical measurements of saccharides even at millimolar concentration levels.

Monitoring of Water Spectral Pattern Reveals Differences in Probiotics Growth When Used for Rapid Bacteria Selection.

Development of efficient screening method coupled with cell functionality evaluation is highly needed in contemporary microbiology. The presented novel concept and fast non-destructive method brings in to play the water spectral pattern of the solution as a molecular fingerprint of the cell culture system. To elucidate the concept, NIR spectroscopy with Aquaphotomics were applied to monitor the growth of sixteen Lactobacillus bulgaricus one Lactobacillus pentosus and one Lactobacillus gasseri bacteria strains. Their growth rate, maximal optical density, low pH and bile tolerances were measured and further used as a reference data for analysis of the simultaneously acquired spectral data. The acquired spectral data in the region of 1100-1850nm was subjected to various multivariate data analyses - PCA, OPLS-DA, PLSR. The results showed high accuracy of bacteria strains classification according to their probiotic strength. Most informative spectral fingerprints covered the first overtone of water, emphasizing the relation of water molecular system to cell functionality.