Razvoj pametne viskozne tkanine s temperaturnim in pH pogojenim uravnavanjem vlage in protimikrobno učinkovitostjo

Glažar, Dominika (author), Tomšič, Brigita (mentor)

Namen raziskave je bil razviti pametno viskozno tkanino s temperaturno in pH odzivnimi lastnostmi ter proaktivnim protimikrobnim delovanjem. Uporabljen je bil mikrogel poli-(N-izopropilakrilamid)/hitozan (PNCS) kot nosilec srebrovih nanodelcev (Ag ND), sintetiziranih s postopkom zelene biosinteze z uporabo 1 in 5 mM raztopine AgNO3 in ekstrakta listov octovca. Mikrogel PNCS in Ag ND so bili nanešeni na viskozno tkanino po eno- in dvostopenjskem postopku. Enostopenjski postopek je vključeval in situ sintezo Ag ND v prisotnosti viskozne tkanine, predhodno modificirane z mikrogelom PNCS, in polisiloksanske matrice, dvostopenjski postopek pa neposredno vstavitev Ag ND preko dehidratacije in ponovne hidratacije mikrogela PNCS v nanodisperziji Ag ND in ekstrakta octovca ter naknaden nanos funkcionaliziranega mikrogela PNCS na viskozna vlakna oplaščena s polisiloksansko matrico. Rezultati preiskav morfoloških, kemijskih in funkcionalnih lastnosti modificiranih vzorcev so pokazali, da je mikrogel PNCS na viskoznih vlaknih ustrezen nosilec biosintetiziranih Ag ND z ekstraktom octovca, pri čemer ima velik vpliv postopek nanosa. V primerjavi z dvostopenjskim nanosom je enostopenjski nanos izkazal višjo koncentracijo Ag ND na vlaknih, ki so v kombinaciji s fenolnimi komponentami ekstrakta octovca obarvali vzorce v rjavo do rjavo-zeleno barvo in zagotovili UV-zaščito z vrednostjo ultravijoličnega zaščitnega faktorja (UZF) 50+. Postopek nanosa in koncentracija Ag ND sta vplivala na nekoliko slabšo temperaturno odzivnost mikrogela PNCS. Medtem, ko je višanje koncentracije Ag ND vplivalo na nižjo temperaturno odzivnost mikrogela PNCS, je postopek nanosa vplival na pH odzivnost, ki se je v večji meri ohranila na vzorcih, modificiranih po dvostopenjskem postopku. Skladno z višjo koncentracijo Ag ND sta vzorca, modificirana po dvostopenjskem postopku, izkazala odlično (> 90-odstotno) redukcijo testnih bakterij E. coli in S. aureus. V tem primeru je mikrogel PNCS deloval kot rezervoar za Ag ND, katerih sproščanje je temeljilo na difuzijsko kontroliranem mehanizmu zaradi povečane poroznosti mikrogela PNCS, ko je ta v nabreklem stanju.

• Language: Slovenian
• Keywords: pametne tekstilije, odzivni hidrogel poli(N-izopropilakrilamid)/hitozan, zelena biosinteza, Ag ND, protimikrobna aktivnost, UV-zaščita
• Work type: Master's thesis/paper
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Year: 2021
• PID: 20.500.12556/RUL-130113
• Publication date in RUL: 10.09.2021

Secondary language

• Language: English
• Title: Development of smart viscose fabric with temperature and pH conditioned moisture management and antimicrobial activity

Abstract

The aim of the research was to develop a smart viscose fabric with temperature and pH responsive properties and proactive antimicrobial protection. Poly-(N-isopropylakrylamide)/chitosan (PNCS) microgel was used as the carrier of silver nanoparticles (Ag NPs), which were synthesised by green biosynthesis using 1 and 5 mM solution of AgNO3 and sumac leaf extract. PNCS microgel and Ag NP were applied to the viscose fabric using a one-step and a two-step process. The one-step procedure involved the in situ synthesis of Ag NPs on the surface of viscose fibres previously modified with PNCS microgel and polysiloxane matrix. The two-step procedure, on the other hand, involved the direct immobilisation of Ag NPs by dehydration/hydration of the PNCS microgel with the nanodispersion of Ag NPs in sumac leaf extract and subsequent application to the polysiloxane matrix-coated viscose fibres. The results of morphological, chemical and functional properties of the modified samples showed that the PNCS microgel is a suitable carrier for biosynthesized Ag NPs on the surface of the viscose fibres, with a significant effect on the application process. Compared to the two-step process, the one-step process showed a higher concentration of Ag NPs on the fibres, which in combination with the phenolic components of the sumac leaf extract coloured the samples brown to brown-green and provided UV protection with a UPF value of 50+. The application procedure and concentration of Ag NPs slightly hindered the temperature response of the PNCS microgel. While increasing the Ag NPs concentration resulted in lower temperature sensitivity of the PNCS microgel, the application procedure affected the pH response, which was better maintained in the samples modified by the two-step process. In agreement with the higher concentration of Ag NPs, the samples modified by the two-step process showed excellent (more than 90%) reduction of the test bacteria E. coli and S. aureus. In this case, the PNCS microgel acted as a reservoir for Ag NPs, whose release was based on a diffusion-controlled mechanism due to the increased porosity of the PNCS microgel in the swollen phase.

• Keywords: smart textiles, responsive hydrogel poly(N-isopropylakrylamide)/chitosan, green biosynthesis, Ag NPs, antimicrobial activity, UV-protection