Potentiometric PVC nanoparticles enriched surfactant sensor

Novi potenciometrijski senzor za anionske tenzide pripremljen je na osnovi višestjenčanih ugljikovih nanocjevčica (MWCNT) koji su upotrebljene za imobilizaciju 1,3-didecil-2-metilimidazol tetrafenilborat (DMI-TPB) ionskog para kao ionofora u membrani. Istraživani senzor pokazao je Nernstovski odziv za dodecilbenzensulfonat i dodecilsulfat. Odziv je prikazan unutar 8-10 sekundi za svaku deseterostruku promjenu koncentracije u rasponu od 1 x 10-7 M do 1 x 10-3 M. Granice detekcije za DBS i DS su 1 x 10-6 i 2 x 10-7 M. Senzor daje stabilan potenciometrijski odziv, te pokazuje zadovoljavajuću selektivnost za DS. Glavna primjena senzora je bila u otkrivanju završnih točaka u potenciometrijskim titracijama anionskih tenzida. Hyamine 1622, heksadeciltrimetilamonijev bromid i cetilpiridinijev klorid su testirani kao potencijalni kationski titranti i svi su dali analitički upotrebljive titracijske krivulje s dobro definiranim točkama ekvivalencije. Operativni životni vijek opisanog senzora je oko 3 mjeseca.A new potentiometric anionic surfactant sensor was prepared based on multi-walled carbon nanotubes (MWCNTs) used for immobilisation of 1,3-didecyl-2-methylimidazolium tetraphenylborate (DMI-TPB) ion pair as ionophore in the membrane. The investigated sensor showed a Nernstian response for both dodecylbenzenesulphonate and dodecyl sulphate. It responded in 8-10 seconds for each ten-fold concentration change in the range of 1 x 10-7 M to 1 x 10-3 M. The detection limits for DBS and DS were 1 x 10-6 and 2 x 10-7 M, respectively. The sensor revealed a stable potentiometric response and exhibited satisfactory selectivity for DS. The main application of the sensor was in the end-point detection in potentiometric titrations of anionic surfactants. Hyamine 1622, hexadecyltrimethylammonium bromide and cetylpyridinium chloride were tested as potential cationic titrants, and all exhibited analytically usable titration curves with well-defined equivalence point. The operational life time of the sensor described amounted ca. 3 months

Water for all : Proceedings of the 7th international scientific and professional conference Water for all

The 7th International Scientific and Professional Conference Water for all is organized to honour the World Water Day by the Josip Juraj Strossmayer University of Osijek, European Hygienic Engineering & Design Group (EHEDG), Danube Parks, Croatian Food Agency, Croatian Water, Faculty of Food Technology Osijek, Faculty of Agriculture in Osijek, Faculty of Civil Engineering Osijek, Josip Juraj Strossmayer University of Osijek Department of Biology, Josip Juraj Strossmayer University of Osijek Department of Chemistry, Nature Park “Kopački rit”, Osijek- Baranja County, Public Health Institute of the Osijek- Baranja County and „Vodovod-Osijek“ -water supply company in Osijek. The topic of World Water Day 2017 was "Wastewater" emphasizing the importance and influence of wastewater treatments on global environment. The international scientific and professional conference Water for all is a gathering of scientists and experts in the field of water management, including chemists, biologists, civil and agriculture engineers, with a goal to remind people about the significance of fresh water and to promote an interdisciplinary approach and sustainability for fresh water resource management. The Conference has been held since 2011. About 300 scientists and engineers submitted 95 abstracts to the 7th International Scientific and Professional Conference Water for all, out of which 33 was presented orally and 62 as posters. 47 full papers were accepted by the Scientific Committee. 38 full papers became the part of the this Proceedings while 9 papers were accepted for publication in Croatian Journal of Food Science and Technology and Electronic Journal of the Faculty of Civil Engineering Osijek - e-GFOS

Catalytic templated length-controlled oligomerization

Templated synthesis is an intriguing strategy for the length-controlled synthesis of oligomers. Traditionally, such reactions require stoichiometric amounts of the template with respect to the product. Recently we reported catalytic macrocyclic templates that promote oligomerization of a small molecule substrate with a remarkable degree of length control. Herein we present our efforts toward creating linear templates for catalytic length-controlled oligomer synthesis.ISSN:1359-6640ISSN:1364-549

Targeting a large active site : structure-based design of nanomolar inhibitors of Trypanosoma brucei trypanothione reductase

Trypanothione reductase (TR) plays a key role in the unique redox metabolism of trypanosomatids, the causative agents of human African trypanosomiasis (HAT), Chagas' disease, and leishmaniases. Introduction of a new, lean propargylic vector to a known class of TR inhibitors resulted in the strongest reported competitive inhibitor of Trypanosoma (T.) brucei TR, with an inhibition constant K; i; of 73 nm, which is fully selective against human glutathione reductase (hGR). The best ligands exhibited in vitro IC; 50; values (half-maximal inhibitory concentration) against the HAT pathogen, T. brucei rhodesiense, in the mid-nanomolar range, reaching down to 50 nm. X-Ray co-crystal structures confirmed the binding mode of the ligands and revealed the presence of a HEPES buffer molecule in the large active site. Extension of the propargylic vector, guided by structure-based design, to replace the HEPES buffer molecule should give inhibitors with low nanomolar K; i; and IC; 50; values for in vivo studies