СОРБЦИОННО-ФОТОМЕТРИЧЕСКОЕ И ТЕСТ-ОПРЕДЕЛЕНИЕ ОБЩЕГО СОДЕРЖАНИЯ ЖЕЛЕЗА В ПРИРОДНЫХ ВОДАХ С ИСПОЛЬЗОВАНИЕМ СОРБЕНТОВ НА ОСНОВЕ ОКСИДА ЦИРКОНИЯ, МОДИФИЦИРОВАННОГО ПОЛИГЕКСАМЕТИЛЕНГУАНИДИНОМ, ФЕРРОЗИНОМ И ФЕРЕНОМ С С.Л. Дидух, А.Н. Мухина, В.Н. Лосев

The zirconium oxide based sorbents  were prepared by modifying polyhexamethylene guanidine, Ferrozine or Ferene S. Optimal conditions were found for modifying the zirconium oxide by Ferrozine and Ferene S. The sorption capacity of the sorbents is 25 mM/g for Ferrozine and 5 mM/g for Feren S. The sorbents quantitatively extract the iron(II)   from solutions of pH 2.5 – 7.0. Intensively colored iron(II) complexes are formed on the sorbents surface during sorption from solutions of pH 2.5 – 5.0 during 20 min. The diffuse reflectance spectra have maxima at 560 and 600 nm for the sorbents with the functional groups of Ferrozine and Ferene S, respectively. This effect was suggested for development of procedures of sorption-photometric and visual test determination of iron(II). The calibration curves were linear over the range 0.1 – 4.0 μg per0,1 gof the sorbent. The limit of detection sorption-photometric determination of iron (II) calculated by the 3s-criterion is 0.006 mg / 0.015 mg and 0.1g / 0.1g for sorbents with functional groups of Ferrozine and Ferene S, respectively. The proposed method was used for determination of total iron in natural waters. The results of sorption-photometric determination of total iron were confirmed by the results of atomic-emission method with inductively coupled plasma.Keywords: Adsorption, modified zirconium oxide, Ferene S, Ferrozine, Iron(II), Diffuse reflectance spectroscopy, test-systems. (Russian)DOI: http://dx.doi.org/10.15826/analitika.2014.18.4.009 S.L. Didukh, A.N. Mukhina, V.N. Losev Research Engineering Centre ‘Kristall’ of Siberian Federal University, Krasnoiarsk, Russian FederationREFERENCES1. Analytical measurements in aquatic environments. Ed. by Namiensnik J., Szefer P. CRC Press, 2010. 503 p.2. Marchenko Z., Bal’tsezhak M. Metody spectrofotometrii v UF i vidimoi oblastiakh v neorganicheskom analize [Spectrophotometric methods in UV and VIS ranges in inorganic analysis]. Moscow, Binom, 2007. 711 p. (in Russian)3. Haghighi B., Safavi A. Simultaneous flow injction determination of iron(II) and iron(III) with opto-electrochemical detection. Anal. Chim. Acta, 1997, vol. 354, pp. 43-50. doi: 10.1016/S0003-2670(97)00436-4.4. Mulaudzi L.V., van Staden J.F., Stefan R.I. On-line determination of iron(II) and iron(III) using a spectrophotometric sequential injection system. Anal. Chim. Acta, 2002, vol. 467, pp. 35-49. doi: 10.1016/S0003-2670(02)00128-9.5. Ermolenko Iu.V., Gridina N.N., Sokolovskaia A.P. [Chemical-analytical system Fe (III) - tyrone - chitosan for spectrophotometry determination of iron]. Uspekhi v khimii i khimicheskoi tekhnologii [Advances in chemistry and chemical technology], 2011, vol. 25, no. 2, pp. 50-55 (in Russian).6. Zhenpu Wang, Cheng K.L. Spectrophotometric Determination of Iron with 1,10-phenanthroline in the Presence of Copper. Microchimica Acta, 1982, II, pp. 115-124. doi: 10.1007/BF012066977. Van Staden J.F., Naidoo E.B. Determination of total iron as Fe(II) in multivitamins, haеmatinics and natural waters using a sequential injection system. South African Journal of Chemistry, 2000, vol. 53, no. 3, pp. 191-205.8. Jankiewicz B., Ptaszynski B., Turek A. Spectrophotometric Determination of Iron(II) in the Soil of Selected Allotment gardens in Lodz. Polish Journal of Environmental Studie, 2002, vol. 11, no. 6, pp. 745-749.9. Fresenius W., Schneider W. For the determination of iron(II) and total iron with 2,2'-dipyridyl in mineral waters. Reduction of iron(III) with ascorbic acid. Z. analyt. Chem, 1976, vol. 209, pp. 340-341.10. Stauffer M.T., Weller W.E., Kubas K.R., Casoni K.A. Limiting reactants in chemical analysis: influences of metals and ligands on calibration curves and formation constants for selected iron-ligand chelates. Stoichiometry and Research – The Impotance of Quantity in Biomedicine, 2012, pp. 311-334.11. Tsurubou S., Sakai T. High-sensitivity extraction - Spectrophotometric determination of iron with 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetrabromophenolphthalein ethyl ester. The Analyst, 1984, vol. 109, pp. 1397-1399. doi: 10.1039/AN9840901397.12. Nagahiro T., Uesugi K., Mehra M.C., Satake M. Spectrophotometric determination of iron(II) after separation by adsorption of its complex with 3-(4-phenyl-2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetraphenylborate on microcrystalline naphthalene. Talanta, 1985, vol. 31, no. 12, рр. 1112-1114. doi: 10.1016/0039-9140(84)80259-3.13. Ying Chen, Chang-Ming Ding, Tian-Ze Zhou, Da-Yong Qi. Organic solvent-soluble membrane filters for the preconcentration and spectrophotometric determination of iron(II) traces in water with Ferrozine. Fresenius J. Anal. Chem, 1999, vol. 363, рр. 119-120. doi: 10.1007/s002160051152.14. Zolotov Iu.A., Tsizin G.I., Dmitrienko S.G., Morosanova E.I. Sоrbtsiоnnое kоntsеntrirovaniе mikrоkоmpоnеntov iz rаstvоrоv [Sorption concentration of micro components from solutions]. Moscow, Science, 2007. 320 p. (in Russian).15. Lisichkin G.V., Fadeev A.Y., Serdan A.A., Mingalyov P.G., Nesterenko P.N., Furman D.B. Khimiia privitykh pоvеrkhnоstnykh soеdinеnii [Chemistry of Surface Grafted Compounds]. Moscow, Fizmatlit, 2003. 592 p. (in Russian).16. Losev V.N., Didukh S.L., Trofimchuk A.K. [Sorption photometric determination of iron using sorbents on the basis of inorganic oxides having functional groups of 4,7-diphenyl-1,10-phenanthroline]. Izvestiia vyzov. Khimiia i khimicheskaia technologiia [Chemistry and chemical technology], 2009, vol. 52, no. 7, pp. 32-36 (in Russian).17. Shvartsenbach G. Flashka G. Kompleksonometricheskoe titrovanie [Complexometric Titration]. Moscow, Chemistry, 1970. 360 p. (in Russian).18. Rеshetniak Е.А., Kholina Yu.V., Shеvchenko V.N. [The color scales constraction for visual colorimetry. Representation of analysis results]. Меtоdy i оb”еkty khimicheskogo analiza [Methods and objects of chemical analysis], 2011, vol. 6, no 4, pp. 188-197 (in Russian).Получены сорбенты на основе оксида циркония, последовательно модифицированного полигексаметиленгуанидином, феррозином и ференом С.  Найдены оптимальные условия модифицирования аминированной поверхности оксида циркония феррозином и ференом С. Сорбционная емкость по отношению к органическим реагентам составляет 25 мкМ/г для феррозина и 5 мкМ/г для ферена С. Синтезированные сорбенты количественно извлекают железо(II) из растворов с рН = 2.5-7.0. При сорбции на поверхности сорбентов образуются интенсивно окрашенные комплексы железа(II), имеющие в спектре диффузного отражения широкую полосу с максимумом при 560 и 600 нм соответственно для сорбентов с функциональными группами феррозина и ферена С. Максимальная интенсивность окраски развивается в течение 20 мин при рН = 2.5-5.0. Образование окрашенных комплексов на поверхности сорбента использовано при разработке методик сорбционно-фотометрического и тест-определения железа(II). Градуировочные графики линейны в диапазоне от 0.1 до 4.0 мкг/0.1 г. Предел обнаружения железа(II) сорбционно-фотометрическим методом, рассчитанный по 3s-критерию, равен  0.006 мкг/0.1 г и 0.015 мкг/0.1 г  для сорбентов с функциональными группами феррозина и ферена С, соответственно. Методики использованы при определении общего содержания железа в природных водах. Правильность методик подтверждена атомно-эмиссионным методом с индуктивно связанной плазмой.Ключевые слова: сорбционное концентрирование, модифицированный оксид циркония, феррозин,  ферен С, железо(II), сорбционно-фотометрическое определение, тест-системы.DOI: http://dx.doi.org/10.15826/analitika.2014.18.4.009ЛИТЕРАТУРАAnalytical measurements in aquatic environments. Ed. by Namiensnik J., Szefer P. CRC Press, 2010. 503 p.Марченко З., Бальцежак М. Методы спектрофотометрии в УФ и видимой областях в неорганическом анализе: пер. с польского А.В. Гармаша. М.: БИНОМ, 2007. 711 с. Haghighi B., Safavi A. Simultaneous flow injction determination of iron(II) and iron(III) with opto-electrochemical detection // Anal. Chim. Acta. 1997. V. 354. P. 43-50.Mulaudzi L.V. van Staden J.F., Stefan R.I.  On-line determination of iron(II) and iron(III) using a spectrophotometric sequential injection system // Anal. Chim. Acta. 2002. V. 467. P. 35-49.Ермоленко Ю.В., Гридина Н.Н., Соколовская А.П. Химико-аналитическая система Fe(III) – тайрон – хитозан в спектрофотометрии железа // Успехи в химии и химической технологии. 2011. Т. 25, № 2. С. 50-55.Zhenpu W., Cheng K.L. Spectrophotometric Determination of Iron with 1,10-phenanthroline in the Presence of Copper // Microchimica Acta. 1982. II. P. 115-124.Van Staden J.F., Naidoo E.B. Determination of total iron as Fe(II) in multivitamins, haеmatinics and natural waters using a sequential injection system // South African Journal of Chemistry. 2000. V. 53, № 3. P. 191-205.Jankiewicz B., Ptaszynski B., Turek A. Spectrophotometric Determination of Iron(II) in the Soil of Selected Allotment gardens in Lodz // Polish Journal of Environmental Studies. 2002. V. 11, № 6. P. 745-749.Fresenius W., Schneider W. For the determination of iron(II) and total iron with 2,2'-dipyridyl in mineral waters. Reduction of iron(III) with ascorbic acid // Z. analyt. Chem. 1976. V. 209. P. 340-341.Limiting reactants in chemical analysis: influences of metals and ligands on calibration curves and formation constants for selected iron-ligand chelates / M. Stauffer [et al.] // Stoichiometry and Research – The Impotance of Quantity in Biomedicine. 2012. P. 311-334.Tsurubou S., Sakai T. High-sensitivity extraction – Spectrophotometric determination of iron with 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetrabromophenolphthalein ethyl ester // The Analyst. 1984. V. 109. P. 1397-1399.Spectrophotometric determination of iron(II) after separation by adsorption of its complex with 3-(4-phenyl-2-pyridyl)-5,6-diphenyl-1,2,4-triazine and tetraphenylborate on microcrystalline naphthalene / T. Nagahiro [et al.] // Talanta. V. 31, № 12. 1985. P. 1112-1114.Organic solvent-soluble membrane filters for the preconcentration and spectrophotometric determination of iron(II) traces in water with Ferrozine / Ying Chen [et al.] // Fresenius J Anal Chem. 1999. V. 363. P. 119-120.Сорбционное концентрирование микрокомпонентов из растворов / Ю.А. Золотов [и др.]. М.: Наука, 2007. 320 с.Химия привитых поверхностных соединений / Г.В. Лисичкин [и др.] М.: Физматлит, 2003. 592 с.Лосев В.Н., Дидух С.Л., Трофимчук А.К. Сорбционно-фотометрическое определение железа с использованием сорбентов на основе неорганических оксидов с функциональными группами 4,7-дифенил-1,10-фенантролина // Известия вузов. Химия и химическая технология. 2009. Т.52, № 7. С. 32-36.Шварценбах Г., Флашка Г.  Комплексонометрическое титрование. М.: Химия, 1970. 360 с.Решетняк Е.А., Холина Ю.В., Шевченко В.Н. Построение цветовых шкал для визуальной колориметрии. Представление результатов анализа // Методы и объекты химического анализа. 2011. Т. 6, № 4. С. 188-19

Simple model of complex dynamics of activity patterns in developing networks of neuronal cultures

Living neuronal networks in dissociated neuronal cultures are widely known for their ability to generate highly robust spatiotemporal activity patterns in various experimental conditions. These include neuronal avalanches satisfying the power scaling law and thereby exemplifying self-organized criticality in living systems. A crucial question is how these patterns can be explained and modeled in a way that is biologically meaningful, mathematically tractable and yet broad enough to account for neuronal heterogeneity and complexity. Here we propose a simple model which may offer an answer to this question. Our derivations are based on just few phenomenological observations concerning input-output behavior of an isolated neuron. A distinctive feature of the model is that at the simplest level of description it comprises of only two variables, a network activity variable and an exogenous variable corresponding to energy needed to sustain the activity and modulate the efficacy of signal transmission. Strikingly, this simple model is already capable of explaining emergence of network spikes and bursts in developing neuronal cultures. The model behavior and predictions are supported by empirical observations and published experimental evidence on cultured neurons behavior exposed to oxygen and energy deprivation. At the larger, network scale, introduction of the energy-dependent regulatory mechanism enables the network to balance on the edge of the network percolation transition. Network activity in this state shows population bursts satisfying the scaling avalanche conditions. This network state is self-sustainable and represents a balance between global network-wide processes and spontaneous activity of individual elements

Ecological features of cyanobacteria and algae communities of the littoral of the meromictic Lake Shira (Khakassia Republic, Russia)

During the study of cyanobacteria and algae from littoral of the meromictic Lake Shira (Republic of Khakas- sia, Russia) forty-eight taxa were identified: Cyanobacteria – 7, Chlorophyta – 5, and Bacillariophyta – 36 species. Cyanobacteria were represented by cosmopolitan taxa Leptolyngbya voronichiniana, cf. Trichocoleus hospitus and widely distributed in the freshwater ecosystems species Phormidium cf. paulsenianum, Pseudophormidium cf. golenkinianum, P. pauciramosum, Leptolyngbya perforans, and L. subtilissima. Among green algae typical freshwater taxa Chloroidium saccharophilum, Desmodesmus abundans, Oocystis lacustris, Chlorella sp., Stigeoclonium sp. were detected. Among Bacillariophyta the most frequent species were Amphora ovalis, Cymbella affinis, Encyonema silesiacum, Eunotia fallax, Gomphonella olivacea, G. parvulum, Kobayasiella subtilissima, Navicula minima, N. radiosa, N. veneta, Nitzchia fonti- cola, N. palea, Grunowia tabellaria, Surirella undulata. Several rare species cf. Fragilaria tenera, Grunowia tabellaria and cf. Ulnaria capitata were found. In relation to mineralization indifferents was the largest group (73%). In relation to pH, a unique feature of the investigated lake was the predominance of alkaliphilic species of diatoms (56%), such as Amphora ovalis, Cymbella affinis, Gomphonema truncatum, Hantzschia amphioxys, Navicula minima, N. veneta, Nitzschia cf. linearis, N. palea, Planothidium lanceolatum and other. In the geographic structure cosmopolitan group included 25 species (69%), boreal group – 4 species (11%), arcto-apline group – 2 species (6%). To obtain more accurate informa- tion on the biodiversity of cyanobacteria and algae of Lake Shira further studies using molecular-genetic and electron microscopic methods are needed

Sapphire shaped crystals for laser-assisted cryodestruction of biological tissues

We have developed cryo-applicators based on the sapphire shaped crystals fabricated using the edge-defined film-fed growth (EFG) and noncapillary shaping (NCS) techniques. Due to the unique physical properties of sapphire: i.e. high thermal, mechanical, and chemical strength, impressive thermal conductivity and optical transparency, these cryo-applicators yield combination of the tissue cryo-destruction with its exposure to laser radiation for controlling the thermal regimes of cryosurgery, and with the optical diagnosis of tissue freezing. We have applied the proposed sapphire cryo-applicators for the destruction of tissues in vitro. The observed results highlight the prospectives of the sapphire cryo-applicators in cryosurgery

Adenomatous lesions of the major duodenal papilla in conjunction with pancreatic heterotopia

The study was carried out on the material of 327 pathoanatomical autopsies taking into account the sex, age, clinical data, pathoanatomical, and clinical diagnoses. The material is divided into two groups: The 1st group - without an ectopic pancreatic tissue in the major duodenum papilla (279 cases) and the 2nd group - with different variants of ectopic pancreatic tissue (48 cases). In each of them, the distribution was carried out according to sex, age, and cause of deat

Evaluation of rat brain morphology following the induction of acute meningitis treated with Ceftriaxone

The present study aimed to assess the histological and immunohistochemical characteristics of the brain of rats that underwent induced acute purulent pneumococcal meningitis after antibiotic therapy with Ceftriaxon

Future Teachers’ Attitude to the Security Problem and Counter Terrorism

The relevance of the theme under study is determined by the problem of ensuring stability and security of the society through young people’s attitude to terrorism. The human community must be able to protect a person’s world outlook, educational, scientific and cultural needs that determine a person’s existence and mental world. One of the key trends in the fight against extremist and terrorist acts in the social environment is their prevention. It is especially important to carry out such preventive measures among young people. The rising generation appears to be the most unprotected category of the population susceptible to the influence of xenophobia destroying traditional values of national cultures and religions which is in a peculiar kind of a spiritual and axiological vacuum. 79 students of 1-5 years of study at the age of 17 - 22 were questioned according to the test-questionnaire ‘Young people’s attitude to terrorism’. Almost all respondents (95%) confirmed that terrorism is dangerous for the society and the problem really exists. Most respondents distinguish such qualities as cruelty, mercenariness, quick temper, and instability when describing a terrorist’s portrait. When analyzing major reasons why people become terrorists, the students gave the first place to striving to feel power over people. Among other important reasons that influence a terrorist’s personality development, they stated commitment to a certain ideology and striving to achieve material wealth. We need an integral system of terrorism prevention including, among other things, its pedagogical foundations. DOI: 10.5901/mjss.2015.v6n3s7p40

State of rat colon microbiocenosis in chronic restraint stress treated with Selank

It is currently accepted that stress significantly affects composition of microbiocenosis due to changes in permeability of intestinal barrier and pro-inflammatory effects. This, in turn, changes behavioral reactions, anxiety and stress response. In this regard, it seems promising to use regulatory peptide-based neurotropic drugs including Selank to correct stress-induced dysbiosis. Our study was aimed at assessing state of rat colon microbiocenosis in modelled chronic restraint stress and treated with Selankby using 65 Wistar male rats divided into five groups (per 13 rats in each): group 1 — rats injected with saline; group 2 — injected with saline and induced chronic restraint stress; group 3–5 — administered with Selank at dose of 80 μg/kg, 250 μg/kg and 750 μg/kg body weight, respectively, and induced chronic restraint stress. Quantitative and qualitative study of animal colon microbiota was carried out according to the method by L.I. Kafarskaja and V.M. Korshunov. Identification of microorganisms was carried out by using a Maldi Biotyper Microflex mass spectrometer (Bruker, United States). Microbial species-specific composition was presented as lg CFU/g mass of examined sample. For each identified microbial genus, the relative mean and frequency of occurrence were calculated. Statistical significance of differences in mean values was determined by using Student’s t-test. Chronic restraint stress in the experiment did not result in affecting dominant microbiota species in rat colon nor reduce their frequency, however, it significantly influenced examined parameters for commensal microbiota disturbing pattern of pathogenic bacterial strains. Use of Selank led to the reversing changes in composition of colonic microbiocenosis caused by stress model. Moreover, magnitude of parameters examined in experiment after applying Selank at dose of 750 μg/kg reached those in non-stressed animals. Thus, effects related to Selank administration may presumably be mediated due to both central and peripheral effects including immunotropic and anti-inflammatory activities which contributed to restoring colon microbiocenosis composition in stress model

Скаффолды как системы доставки биологически активных и лекарственных веществ

The article updates the existing data on the use of scaffolds as target and controlled substance delivery systems. The prerequisites and grounds for using scaffolds as substance delivery systems are being considered. Current tissue-engineered strategies for developing target drug and bioactive substance delivery using scaffolds are being discussed. A classification of scaffold-based substance delivery systems is provided. Special attention is given to the development of two-phase substance delivery systems using various types of nanoparticles. A variety of nanoparticles and the benefits of their use as carriers of substances in a two-component delivery systems are shown. Recent developments in the substance delivery systems for regenerative medicine and future prospects are presented.В статье проанализированы и систематизированы современные данные об использовании скаффолдов как систем контролируемой доставки веществ. Рассматриваются предпосылки и основания для использования скаффолдов в качестве систем доставки. Обсуждаются текущие стратегии создания систем контролируемой доставки биологически активных и лекарственных веществ на основе продуктов скаффолд-технологий. Приводится классификация систем доставки веществ на основе скаффолдов. Отдельное внимание уделено разработкам двухфазных систем доставки веществ с использованием наночастиц. Показано разнообразие наночастиц и их преимущества как носителей веществ, применяемых в двухкомпонентных системах доставки. Приводятся современные примеры разработок систем доставки веществ и перспективы развития регенеративной медицины