Application of surface analytical methods for hazardous situation in the Adriatic Sea: monitoring of organic matter dynamics and oil pollution

Abstract

Abstract. Surface analytical methods are applied to examine the environmental status of seawaters. The present overview emphasizes advantages of combining surface analytical methods, applied to a hazardous situation in the Adriatic Sea, such as monitoring of the first aggregation phases of dissolved organic matter in order to potentially predict the massive mucilage formation and testing of oil spill cleanup. Such an approach, based on fast and direct characterization of organic matter and its high-resolution visualization, sets a continuous-scale description of organic matter from microto nanometre scales. Electrochemical method of chronoamperometry at the dropping mercury electrode meets the requirements for monitoring purposes due to the simple and fast analysis of a large number of natural seawater samples enabling simultaneous differentiation of organic constituents. In contrast, atomic force microscopy allows direct visualization of biotic and abiotic particles and provides an insight into structural organization of marine organic matter at micro-and nanometre scales. In the future, merging data at different spatial scales, taking into account experimental input on micrometre scale, observations on metre scale and modelling on kilometre scale, will be important for developing sophisticated technological platforms for knowledge transfer, reports and maps applicable for the marine environmental protection and management of the coastal area, especially for tourism, fishery and cruiser trafficking.

Salinity-induced chemical, mechanical, and behavioral changes in marine microalgae

“…The electrochemical method of polarography and chronoamperometry of oxygen reduction at the dropping mercury electrode (DME) was utilized to characterize the organic constituents, such as biopolymers and fluid microparticles in the aqueous electrolyte solution based on molecular adsorption or particle adhesion to the DME (Žutić et al 1999Svetličić et al 2006;Pletikapić and Ivošević DeNardis 2017). Briefly, adsorption of organic molecules at the DME interface can be characterized by recording the polarographic maximum of Hg(II) ions, which is an alternative approach to measuring dissolved organic carbon in seawater (Hunter and Liss 1981).…”

Structural Features of the Algal Cell Determine Adhesion Behavior at a Charged Interface

“…In this study polarography and chronoamperometry of oxygen reduction at the dropping mercury electrode (DME) were used. The electrochemical method allows to directly distinguish between dissolved and dispersed organic constituents in the sample based on the specific electrochemical response [23][24][25]30]. Dissolved organic matter is detected through adsorption at the interface in a well defined potential range.…”

“…Taking into account that each amperometric signal corresponds to the adhesion of individual cells, signal frequency linearly increases with cell density in the range of 10 5 to 10 7 cells L À 1 , enabling translation of frequency into particle concentration [31]. This approach was applied for the monitoring of spatial and temporal distributions of reactive fluid and flexible particles in the Northern Adriatic sea to potentially predict the massive mucilage formation [24,25,33,34].…”

“…Extensive research has been done on the development of an electrochemical method of polarography and chronoamperometry on a charged dropping mercury electrode for characterization of adhered organic particles such as organic droplets, living cells, lipid vesicles, bacterial aggregates, natural fluid, and flexible particles [16][17][18][19][20][21][22][23][24][25]. Electrochemical adhesion detection is based on interfacial properties (hydrophobicity and fluidity) and particle supramolecular organization [23].…”

Molecular Beam Epitaxy and High-Pressure Studies of van der Waals Magnets

“…This tip deflection is picked up by the photodiode Figure 2.9: Basic principle of AFM. Adapted from [128].…”