Transformacije nanodelcev v prebavnem traktu kopenskega raka enakonožca in vitro

Medvešček, Neja (author), Jemec Kokalj, Anita (mentor)

V dosedanjih prehranjevalnih poskusih z enakonožcem Porcellio scaber so na podlagi primerjave kopičenja kovin v prebavni žlezi in količino prvotno dosegljivih kovinskih ionov sklepali, da se nanodelci (ND) v prebavnem traktu dodatno raztapljajo. V magistrski nalogi smo zato želeli ugotoviti, kako se spremeni raztapljanje nanodelcev zlata (Au), bakrovega oksida (CuO) in srebra (Ag) v simuliranem prebavnem soku enakonožca. Predvidevali smo, da organske komponente simuliranega prebavnega soka, proteini BSA (goveji serumski albumin), surfaktanti SDS (natrijev dodecilsulfat) in iztrebki (vir mikroorganizmov in organske snovi) vplivajo na raztapljanje ND. Rezultate in vitro poskusov smo primerjali z rezultati prehranjevalnih poskusov, kjer smo spremljali kopičenje kovin v prebavni žlezi. Au ND se v prebavnem soku niso raztapljali, kar je v skladu s predpostavko o njihovi inertnosti. V nasprotju z našimi pričakovanji prisotnost BSA in SDS ni povečala raztapljanja CuO- in Ag ND. Iztrebki niso dodatno vplivali na raztapljanje Ag ND, kar smo dokazali z uporabo metode sp-ICP-MS. Rezultati in vivo in in vitro poskusov so bili primerljivi le v primeru Au ND. S tehniko sp-ICP-MS smo dokazali, da se Au ND ne kopičijo v žlezi. V in vivo poskusu z Ag ND smo dobili lažno pozitivne rezultate o kopičenju Ag ND v žlezi. Predlagamo nadaljnje raziskave z Ag- in CuO ND, uporabo drugih komercialnih proteinov in surfaktantov, uporabo bolj napredne metode sp-ICP-MS in optimizacijo protokola za razklop vzorcev.

• Language: Slovenian
• Keywords: nanodelci, bakrov oksid, srebro, zlato, raztapljanje, in vitro, prebavni sok, kopenski rak enakonožec Porcellio scaber
• Work type: Master's thesis/paper
• Organization: BF - Biotechnical Faculty
• Year: 2018
• PID: 20.500.12556/RUL-103172
• COBISS.SI-ID: 4890447
• Publication date in RUL: 14.09.2018

Secondary language

• Language: Unknown
• Title: Transformation of nanoparticles inside the gut lumen of terrestrial isopod in vitro

Abstract

Recent in vivo studies using isopod Porcellio scaber have proposed that metal nanoparticles (NPs) dissolve in the gut lumen which results in increased bioassimilation of metals in hepatopancreas in comparison to actually bioavailable free metal ions offered in food. In this thesis we wanted to examine the dissolution of gold (Au), copper oxide (CuO) and silver (Ag) NPs in simulated isopod gastric juice. We hypothesized, that organic compounds in simulated gastric juice, BSA protein (bovine serum albumin), SDS surfactant (sodium dodecly sulfate) and feces (source of microorganisms and organic matter), contribute to increased dissolution of NPs. We also compared the results of in vitro studies to results of in vivo studies where we assesed the assimilation of metals inside the gland. Gold NPs did not dissolve in the gastric juice which is in line with expectations. Contrary to our expectations, BSA and SDS did not influence the dissolution of CuO- and Ag NPs. Also feces did not affect the dissoluiton of Ag NPs. The latter was proved with use of sp-ICP-MS method. The results of in vivo studies were comparable to those of in vitro with Au NPs only. With sp-ICP-MS, we proved that Au NPs do not accumulate in hepatopancreas. The results of in vivo experiment with Ag NPs showed false positive results of Ag NPs accumulating in the gland. We suggest further research on Ag- and CuO NPs and use of other commercial proteins and surfactants. Also use of advanced methods, such as sp-ICP-MS and optimisation of the protocol of digestion of the samples is suggested.

• Keywords: nanoparticles, copper oxide, silver, gold, dissolution, in vitro, gastric juice, terrestrial isopod Porcellio scaber