Extinction at 400 nm is a convenient, cheap, and fast method for in situ determination of Au concentration in colloids with good accuracy even in the presence of Au(+3) ions and other interference factors. However, these possibilities have been validated only with common citrate gold nanospheres and, in part, with gold nanorods. Here, we demonstrate the universality of the UV−vis extinction method with six experimental and theoretical models: (1) CTAC-stabilized gold nanospheres; (2) small and large nanosphere clusters; (3) gold nanorods with plasmon resonances (PRs) ranging from 670 to 980 nm; (4) 2D nanotriangles and (5) 2D nanoplates with PRs from 600 to 775 nm; and (6) gold nanostars with PRs from 680 to 820 nm. In total, we fabricated 34 samples with different nanoparticle sizes, shapes, morphologies, and Au concentrations. From COMSOL, T-matrix, and generalized multiparticle Mie simulations, we derived a universal relation between the extinction cross section and the particle or cluster volume V: C ext (nm 2 ) = 0.51 × V (nm 3 ), 10 2 ≤ V (nm 3 ) ≤ 10 5 , which gives a universal relation between the gold concentration and extinction [Au 0 ] (mM) = 0.44 × A 400 . The same relation is derived from atomic absorption spectroscopy and inductively coupled plasma mass spectroscopy experimental determination of [Au 0 ] concentration correlated with A 400 . While the universality of the derived equation is demonstrated by an unprecedented set of gold nanoparticle sizes, shapes, morphologies, and particle clusters, its accuracy can be limited by 20−30%. This uncertainty results from the light scattering contribution that violates the proportionality between the extinction cross section and the particle or cluster volume. However, for a particular colloidal system, the application of the derived relation can be useful in monitoring reduction or aggregation processes.

The ability of sixteen wood- and soil-inhabiting basidiomycete strains and four ascomycete strains to degrade the most hazardous, widespread, and persistent pollutants (polycyclic aromatic hydrocarbons, oxyethylated nonylphenol, alkylphenol, anthraquinone-type synthetic dyes, and oil) was found. The disappearance of the pollutants, their main metabolites, and some adaptive properties (activities of ligninolytic enzymes, the production of emulsifying compounds and exopolysaccharides) were evaluated. The toxicity of polycyclic aromatic hydrocarbons decreased during degradation. New data were obtained regarding (1) the dependence of the completeness of polycyclic aromatic hydrocarbon degradation on the composition of the ligninolytic enzyme complex; (2) the degradation of neonol AF9-12 by higher fungi (different accessibilities of the oxyethyl chain and the aromatic ring of the molecules to different fungal genera); and (3) the production of an emulsifying agent in response to the presence in the cultivation medium of hydrophobic pollutants as the common property of wood- and soil-inhabiting basidiomycetes and ascomycetes. Promise for use in mycoremediation was shown in the wood-inhabiting basidiomycetes Pleurotus ostreatus f. Florida, Schizophyllum commune, Trametes versicolor MUT 3403, and Trametes versicolor DSM11372; the litter-decomposing basidiomycete Stropharia rugosoannulata; and the ascomycete Cladosporium herbarum. These fungi degrade a wide range of pollutants without accumulation of toxic metabolites and produce ligninolytic enzymes and emulsifying compounds.

Пленарные доклады 1Казанский институт биохимии и биофизики -обособленное структурное подразделение ФИЦ КазНЦ РАН, Казань, Россия 2Казанский (Приволжский) федеральный университет, Казань, Россия, 3Федеральное государственное бюджетное учреждение науки Институт биохимии и физиологии растений и микроорганизмов РАН, Саратов, Россия, 4Институт органической и физической химии им. А.Е. Арбузова -обособленное структурное подразделение ФИЦ КазНЦ РАН, Казань, Россия

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