Title Sinteza kitozanskih nanočestica Title (english) Synthesis of chitozane nanoparticles Author Marta Šimunović Mentor Aleksandar Sečenji (mentor)Granter Josip Juraj Strossmayer University of Osijek Defense date and country 2018-09-15, Croatia Scientific / art field, NATURAL SCIENCES Abstract Tema je ovoga rada sinteza kitozanskih nanočestica, a izbor teme vezan je uz zanimljivost primjenljivosti kitozana na brojnim poljima znanosti. Svrha završnoga rada je optimalizirati način dobivanja nanočestica kitozana u laboratorijskim uvjetima. Brojne su metode priprave nanočestica, metode za pripravu kitozanskih su ionotropic gelation, microemulsion method, emulsification solvent difusion method, polyelectrolyte complexes, reverse micellar method. U ovom završnom radu koristili smo metodu
... More ionotropske gelacije (ionotropic gelation), ova metoda temelji se na povezivanju pomoću elektrostatskih interakcija između protonirane amino skupine kitozana i polianiona. Polimeri su spojevi velike molekulske mase, koji su načinjeni od osnovnih građevnih jedinica monomera koje se međusobno povezuju. Polimeri mogu biti prirodni, polusintetski i sintetski, primjeri prirodnih polimera su proteini, celuloza, škrob, nukleinske kiseline, a među polusintetske spada i kitozan koji se dobiva iz hitina. Hitin
se može naći u nekim biljkama, ali u velikim količinama nalazi se u egzoskeletu člankonožaca i ljušturama školjaka. Kitozan je polimer koji se sastoji od dva monomera Nacetil- 2-amino-2-deoksi-D-glukopiranoza i 2-amino-2deoksi-D-glukopiranoza, koje su
međusobno povezane β-(1→4) glikozidnom vezom. Kitozan se za komercijalne potrebe najčešće dobiva postupkom deacetilacije hitina, koji se dalje koristi za razne potrebe od farmacije, medicine, poljoprivrede, sve do zaštite okoliša. Postupak deacetilizacije je najčešće odvija uz lužinu, kao što je natrijeva ili kalijeva hidroksida pri određenoj temperaturi. Fine čestice kitozana koje su potrebne za različite aplikacije u medicini ili farmaciji često imaju dimenzije manje od 500 nm. Nanočestice su korisne jer imaju posebna svojstva, koja se mogu razlikovati i od istih četica većih dimenzija, upravo zbog svojih malih dimenzija povećava se
aktivna površina čestica. Odnosno razlog za promjenu svojstva kako kemijski tako i fizikalnih jest omjer površine i volumena čestice, odnosno omjer broja atoma koji se nalaze na površini čestice i unutar čestice. U nekim slučajevima nanočestica veći dio atoma može se naći na površini čestica nego u unutrašnjosti. Pomoću dobivenih rezultata ovoga rada mogu se sintetizirati nanočestice kitozana određene veličine pomoću preciznog modeliranja, odnosno preciznog odabira koncentracije i molarne mase kitozana te omjera kitozana i TPP(tripolifosfat). Less Abstract (english) The topic of this paper is the synthesis of chitosan nanoparticles, the theme selection is related to the interestingness of chitosan applicability in many fields of science. The purpose of the thesis is to optimize the method of obtaining chitosan nanoparticles in laboratory conditions. Numerous methods of preparation of nanoparticles exists, for chitosan nanoparticles
preparation methods are: ionotropic gelation, microemulsion method, emulsification solvent diffusion method,
... More polyelectrolyte complexes, reverse micellar method. In this thesis we have used the ionotropic gelation method, this method is based on the linkage by electrostatic atrractive forces between the chitosans protonated amino group and the polyanion. Polymers are compounds of high molecular weight which are made of the basic building blocks of monomers that are interconnected. Polymers can be natural, semi-synthetic and synthetic, examples of natural polymers are proteins, ellulose, starch, nucleic acid, and between polysynthetic and chitosan derived from the chitin. Chitin can be found in some plants, but in large quantities it is found in the exoskeleton of arthropods and shellfish shells. Chitosan is a polymers consisting of two monomers of N-acetyl-2-amino-2-deoxy-D-glucopyranose and 2- amino-2-deoxy-D-glucopyranose which are mutually linked to the β- (1 → 4) glycosidic linkage. Chitosan for commercial needs is most often obtained by the deacetylation process of chitin, which is further used for various purposes from pharmacy, medicine, agriculture to environmental protection. The deacetylation process is most commonly carried out with a base such as sodium or potassium hydroxide at a certain temperature. Fine chitosan particles required for different applications in medicine or pharmacy often have dimensions less than 500 nm. The nanoparticles are useful because they have special properties, which can be different from the large particles made of same material, because of their small dimensions, the active surface increases. The reason for the change of both the chemical and physical properties is that ratio of the surface and the volume of particles, or the ratio of the number of atoms located on the surface of the particle and within the particle. In some cases, most of the
atoms can be found on the surface of the particles rather than in the interior. By means of the results obtained in this work,we can synthesize chitosan nanoparticles of a desired size by precise modeling, ie precise concentration and chitosan molecular mass selection, and chitosan to TPP (tripolyphosphate) ratios. Less Keywords
nanotehnologija
nanočestice
kitozan
nanonosači lijekova
Keywords (english)
nanotechnology
nanoparticles
chitosan
drug nanoparticles
Language croatian URN:NBN urn:nbn:hr:182:732979 Study programme Title: Chemistry Type of resource Text File origin Born digital Access conditions Open access Terms of use Created on 2018-12-18 10:25:50
