Characterization, toxicity and application of newly synthesized ionic liquids for cleaning and conservation of paper heritage artefacts

Abstract

<p>U okviru ove disertacije uspe&scaron;no je sintetisano 14 novih protičnih jonskih tečnosti na bazi amina. Strukture su potvrđene snimanjem NMR i IC spektra. Izmerena je gustina svih jonskih tečnosti u temperaturnom opsegu&nbsp; T&nbsp; = (293,15&nbsp; &ndash;&nbsp; 353,15) K, kao i gustina njihovih vodenih rastvora u temperaturnom opsegu&nbsp; T&nbsp; = (293,15 &ndash; 313,15) K. Fizičko-hemijska karakterizacija je takođe propraćena merenjem viskoznosti i električne provodljivosti binarnih sme&scaron;a u celom rasponu&nbsp; molarnih frakcija i na različitim temperaturama (T&nbsp; = (293,15&nbsp; &ndash;&nbsp; 313,15) K). Na osnovu dobijenih rezultata utvrđeno je da sve protične jonske tečnosti imaju izražen structure making efekat. Ispitana je antimikrobna aktivnost protičnih jonskih tečnosti na bazi amina prema deset sojeva fungi: Trichoderma sp., Penicillium sp.(1-3), Cladoporium sp., Aspergillus sp. (1,2), A. flavus, F. graminearum i P. citrinium,&nbsp; osam sojeva bakterija:&nbsp; B. subtillis (6633), S. aureus (6538), E. faecalis (19433), K. rhizophila (9341),&nbsp; E. coli (11229), S. enteritidis (13076), P. mirabilis (12453), P. aeruginosa (15692) i dva soja kandida:&nbsp; C. albicans (ATCC 10231) i C. albicans (L) .&nbsp; Rezultati su pokazali da svih četrnaest jonskih tečnosti pokazuju antimikrobno delovanje. Za proučavane protične&nbsp; jonske tečnosti, antimikrobna aktivnost zavisi od dužine alkil lanca, pri tome pokazujući maksimalnu aktivnost sa anjonima koji sadrže 3 i 4 atoma ugljenika u nizu. Rezultati su pokazali da PILs pokazuju bolje antimikrobno dejstvo ako istovremeno sadrži i terminalno hlorovani C atom. Međutim, PILs pokazuju veću aktivnost ako je terminalni C atom monohalogeniran, jer monohalogenirani derivati poseduju veći afinitet za interakciju sa ćelijskom membranom. Najefikasnije PILs (ClA, 3-ClP, 4-ClB, Ac i For) su izabrane da se testiraju kao alternativni rastvarači umesto timola. Svih pet protičnih jonskih tečnosti uspe&scaron;no je testirano kao zelena alternativa za uobičajne organske rastvarače koji se koriste za či&scaron;ćenje i konzervaciju papirne povr&scaron;ine. Značajna antimikrobna svojstva primećena u ovoj doktorskoj tezi sugeriraju da proučavane protične jonske tečnosti mogu imati potencijalnu primenu u radu sa papirnim atifaktima, kao i pri njihovom či&scaron;ćenju i konzervaciji, zamenjujući na taj način primenu konvencionalnih rastvarača i organske supstance otrovne za ljude i životnu sredinu.</p>

<p>In this doctoral thesis the 14 amine based protic ionic liquids were newly synthesized. The validity of all structures were checked and confirmed by NMR and IR spectroscopy. Densities of pure ionic liquids and their diluted aqueous solutions have been measured over the whole composition range at selected temperatures from (293.3 to 353.15) K for pure ionic liquids, and from (293.15 to 313.15) K for diluted aqueous solutions. Physico-chemical&nbsp; characterization was also performed&nbsp; measuring the viscosity and electrical conductivity of binary mixtures in the entire range of mole fractions and at different temperatures (T&nbsp; = (293.15&nbsp; &ndash;&nbsp; 313.15) K). It was concluded that all investigated PILs have structure making tendency. Further, antimicrobial activity of amine based protic ionic liquids has been investigated using ten fungi strains: Trichoderma sp., Penicillium sp. (1-3), Cladoporium sp., Aspergillus sp. (1,2), A. flavus, F. graminearum i P. citrinium, eight ATCC bacterial strains: B. subtillis (6633), S. aureus (6538), E. faecalis (19433), K. rhizophila (9341), E. coli (11229), S. enteritidis (13076), P. mirabilis (12453), P. aeruginosa (15692) and two Candida&nbsp; strains:&nbsp; C. albicans (ATCC 10231) i C. albicans (L). The results indicated that all fourteen ionic liquids showed antimicrobial activity.&nbsp; For the studied PILs, the antimicrobial activity dependent on the alkyl chain length, showing maximal activity with anions containing 3 and 4 carbon atoms. The results revealed that the PILs show better antimicrobial activities if the longer alkyl chain is presented but in the same time contain chlorinated terminal C atom. However, PILs showed higer activity if the terminal C atom is monohalogenated, since the monohalogenated derivatives possess higher affinity to interact with cell membrane. The most effective PILs (ClA, 3-ClP, 4-ClB, Ac and For)&nbsp; were chosen to be tested as alternative solvents instead of thymol. All five PILs were successfully tested as the green alternatives to conventionally used organic solvents for paper cleaning and conservation. The significant antimicrobial properties observed in this doctoral thesis suggest that studied PILs may have potential applications in the paper art and artefact cleaning and conservation replacing thus, conventional solvents and organic substances that are toxic for humans and environment.</p>