master's thesis
The effect of type of chitosan on biocompatibility of melatonin-loaded lecithin/chitosan nanoparticles

Mateja Ljubičić (2015)
University of Zagreb
Faculty of Pharmacy and Biochemistry
Department of pharmaceutical technology
Metadata
TitleUtjecaj tipa kitozana na biokompatibilnost lecitinsko-kitozanskih nanočestica s melatoninom
AuthorMateja Ljubičić
Mentor(s)Anita Hafner (thesis advisor)
Abstract
Cijeljenje rane je vrlo kompleksan proces i uključuje interakcije različitih tipova stanica pod kontrolom faktora rasta. U procesu upalne faze fibroblasti migriraju u ranu gdje sintetiziraju i remodeliraju novi izvanstanični matriks. Stanične kulture fibroblasta kože koriste se kao in vitro modeli rane u preliminarnim ispitivanjima biokompatibilnosti i potencijalnog učinka različitih tvari i inovativnih terapijskih sustava na cijeljenje rane kroz učinak na proliferaciju i migraciju stanica. U ovom radu ispitana je biokompatibilnost lecitinsko- kitozanskih nanočestica kao nosača melatonina, sa fibroblastima kože. Nanočestice su pripravljene ionotropnim geliranjem kitozana i lecitina. U pripravi nanočestica korištena su četiri tipa kitozana koja se međusobno razlikuju po molekulskoj masi (50-150 kDa ili 150-400 kDa) i/ili stupnju deacetilacije (75-90 % ili >90 %). Srednji promjer i zeta-potencijal nanočestica ovisili su o molekulskoj masi i stupnju deacetilacije kitozana, te su se kretali u rasponu od 237,8 do 263,4 nm, odnosno od 25,7 do 32,1 mV. Sadržaj melatonina iznosio je do 4,2 %. Biokompatibilnost nanočestica sa fibroblastima kože određena je praćenjem metaboličke aktivnosti stanica nakon dvosatnog izlaganja nanočesticama pri koncentraciji kitozana od 1,25 do 20 μg/ml. Osim o koncentraciji kitozana u sustavu, biokompatibilnost nanočestica ovisila je i o stupnju deacetilacije kitozana. Sve ispitivane suspenzije nanočestica su pri koncentraciji kitozana od 10 i 20 μg/ml značajno smanjivale vijabilnost stanica. U slučaju stanica tretiranih nanočesticama pripravljenim s kitozanom većeg stupnja deacetilacije, vijabilnost se značajno smanjila već pri koncentracijama kitozana od 5 μg/ml. U usporedbi sa suspenzijama nanočestica, otopine kitozana su imale izraženiji citotoksični učinak. Ispitivanjem citotoksičnosti određena je koncentracija kitozana u sustavu pri kojoj ima smisla ispitivati učinak lecitinsko-kitozanskih nanočestica na cijeljenje rane in vitro i ona iznosi 5 μg/ml za suspenzije nanočestica pripravljene s kitozanima manjeg stupnja deacetilacije te 2,5 μg/ml za suspenzije nanočestica pripravljene s kitozanima većeg stupnja deacetilacije.
Keywordschitosan lecithin melatonin nanoparticles biocompatibility in vitro
Parallel title (English)The effect of type of chitosan on biocompatibility of melatonin-loaded lecithin/chitosan nanoparticles
Committee MembersJasmina Lovrić
Lovorka Vujić
Anita Hafner
GranterUniversity of Zagreb
Faculty of Pharmacy and Biochemistry
Lower level organizational unitsDepartment of pharmaceutical technology
PlaceZagreb
StateCroatia
Scientific field, discipline, subdisciplineBIOMEDICINE AND HEALTHCARE
Pharmacy
Pharmacy
Study programme typeuniversity
Study levelintegrated undergraduate and graduate
Study programmePharmacy
Academic title abbreviationmag. pharm.
Genremaster's thesis
Language Croatian
Defense date2015-09-18
Parallel abstract (English)
Wound repair is a complex process that involves an integrated response by many different cell types controlled by a variety of growth factors. During the initial inflammatory phase fibroblasts enter the wound where they synthesize and remodel new extracellular matrix. Fibroblast cell cultures are often used in the design of in vitro wound model for preliminary investigations of biocompatibility and potential wound healing effect of active compounds or innovative delivery systems, through the influence on cell migration and proliferation. In this study, the biocompatibility of melatonin-loaded lecithin/chitosan nanoparticles with skin fibroblasts was investigated. Nanoparticles were prepared by ionotropic gelation of lecithin and chitosan. Four types of chitosan used differed in molecular weight (50-150 kDa or 150-400 kDa) and/or deacetylation degree (75-90 % or >90 %). Mean diameter and zeta potential of nanoparticles depended on molecular weight and deacetylation degree of chitosan and ranged between 237.8 and 263.4 nm and 25.7 and 32.1 mV, respectively. Melatonin loadings were up to 4.2%. Biocompatibility of nanoparticles with skin fibroblasts was determined by evaluation of metabolic activity of cells treated with nanoparticle suspensions at chitosan concentration ranging from 1.25 to 20 μg/ml. Apart from chitosan concentration, biocompatibility of nanoparticles was related to chitosan deacetylation degree. All types of nanoparticles induced a significant decrease in the cell viability at chitosan concentration of 10 and 20 μg/ml. Viability of cells treated with nanoparticles prepared with chitosan of higher deacetylation degree decreased significantly even at chitosan concentration of 5 μg/ml. Chitosan solutions exerted higher cytotoxic effect compared to nanoparticle suspensions. Cytotoxicity studies revealed the chitosan concentration in the system at which it is feasible to study in vitro wound healing effect of lecithin/chitosan nanoparticles, and that is 5 μg/ml for nanoparticle suspensions prepared with chitosan of lower deacetylation degree, and 2.5 μg/ml for nanoparticle suspensions prepared with chitosan of higher deacetylation degree.
Parallel keywords (Croatian)kitozan lecitin melatonin nanočestice biokompatibilnost in vitro
Resource typetext
Access conditionAccess restricted to students and staff of home institution
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:163:788774
CommitterPetra Gašparac