Vpliv dimenzij matrice ter parametrov krogličenja na fizikalne lastnosti pelet, izdelanih s tehnologijo iztiskanja in krogličenja

Žižek, Julija (author), Janković, Biljana (mentor), Smrdel, Polona (co-mentor)

Pelete so majhni, okrogli delci z ozko porazdelitvijo velikosti, ki imajo veliko prednosti v primerjavi z ostalimi farmacevtskimi oblikami. Namen magistrske naloge je bil preučiti vpliv parametrov iztiskanja in krogličenja na lastnosti iztiskanca ter pelet, izdelanih s tehnologijo iztiskanja in krogličenja. Z različnimi tehnikami, kot so določitev temperature, vlage, gostote in mehanskih lastnosti iztiskanca, smo skušali ugotoviti, kako debelina in premer odprtin matrične plošče vplivata na fizikalne lastnosti iztiskanca. Pokazali smo, da z uporabo debelejše matrice dobimo bolj kompakten in plastičen iztiskanec. Te ugotovitve so v skladu z rezultati mehanskih karakterizacij, ki so pokazale, da je najbolj kompakten iztiskanec imel najvišjo plastičnost (pokazano z najmanjšo natezno trdnostjo in Youngovim modulom). V naslednjem koraku smo iztiskance krogličili. Velikost in porazdelitev velikosti ter obliko nastalih pelet smo določili s slikovno analizo delcev (PATVIS APA tehnologija). Dodatno smo porazdelitev velikosti pelet določili tudi s sejalno analizo, površino pa smo si ogledali z optičnim in SEM mikroskopom. Ugotovili smo, da so za velikost ter porazdelitev velikosti pelet najpomembnejši parametri matrične plošče, za obliko pelet pa parametri krogličenja. Večji delež prevelikih pelet smo dobili z uporabo debelejše matrice z večjimi odprtinami, saj je v tem primeru iztiskanec bolj kompakten in se v procesu krogličenja lomi na večje in bolj enakomerne delce, ki pa za ustrezno okroglost potrebujejo daljši čas in višje obrate sferonizatorja. Z uporabo tanjše matrice smo dobili krhek iztiskanec, ki se je med procesom krogličenja lomil na manjše delce. Zlasti pri visoki sferonizacijski hitrosti je bil delež prašne frakcije izredno visok. Zaradi aglomeracije prahu smo v tem primeru dobili tudi širšo porazdelitev velikosti pelet. Najboljši izkoristek (najvišji delež pelet velikosti med 0,71 – 1,12 mm) smo dobili z uporabo najdebelejše matrice (4 mm) in najmanjšim premerom odprtin (0,7 mm). Za okroglost pelet sta pomembna čas krogličenja in obrati sferonizatorja, ki morata biti optimalno določena, saj so bile pelete pri krajšem času in nižjih obratih sferonizatorja nepopolno oblikovane, medtem ko smo pri previsoki sferonizacijski hitrosti dobili več prahu, pri daljšem času pa širšo distribucijo zaradi aglomeracije pelet. Pokazali smo, da se parametri iztiskanja in krogličenja morajo prilagoditi glede na fizikalno-kemijske lastnosti sestavin, iztiskanca ter opreme.

• Language: Slovenian
• Keywords: iztiskanje, krogličenje, dimenzije matrične plošče, čas in hitrost krogličenja, mehanske lastnosti iztiskanca, velikost in oblika pelet, PATVIS APA
• Work type: Master's thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2019
• PID: 20.500.12556/RUL-107969
• Publication date in RUL: 11.06.2019

Secondary language

• Language: English
• Title: Impact of extrusion screen dimensions and spheronization parameters on the physical properties of pellets produced by extrusion and spheronization technology

Abstract

Pellets are small, spherical particulates with a narrow size distribution, which have many advantages over other pharmaceutical forms. The purpose of the master thesis was to study the influence of the extrusion and spheronization parameters on the properties of the extrudates and pellets, prepared with extrusion and spheronization. In further, we determined how the thickness and diameter of the spheronization plate openings influenced the physical properties of the extrudate such as moisture content, density and mechanical characteristics. We have demonstrated that using of a thicker spheronitation plate more compact and plastic extrudates were formed. These findings are in accordance with the higher plasticity of extrudes (lower tensile strengt and Young's modulus). The next step was shperonization of the extrudates. The size and the distribution of the pellets were determined by image-analysis so called PATVIS APA technology. In addition, the size distribution of pellets was also evaluated by sieve analysis, and the surface was visualized using the optical and SEM microscopes. We have established that the properties of the spheronization plate are more important for the size and distribution of the pellets, and spheronization parameters are crucial for their shape. A larger proportion of oversized pellets was obtained by using a thicker plate with larger openings, since the extrudate is more compact and during spheronization process breaks into larger and more evenly distributes particles, which need a longer time and higher spheronizer speed for adequate pellet's sphericity. Using a thinner plate, we obtained a brittle extrudate that was fragmenting to smaller particles during the spheronization process (e.g. at high spheronization speed, the proportion of the dust fraction was significatntly higher). Due to the agglomeration of the dust particles, a wider distribution of the pellet size was also obtained. The best yield (the highest proportion of pellets with size between 0,71 to 1,12 mm) was obtained using the thickest matrix (4 mm) and the smallest opening diameter (0,7 mm). For the spherical shape of the pellets, the spheronization time and spheronizer speed are important, which must be optimally determined. We have shown that the extrusion and ball parameters must be adapted according to the physico-chemical properties of the ingredients, extruders and equipment.

• Keywords: extrusion, spheronization, dimensions of the spheronization plate, time and speed of spheronization process, mechanical properties of the extrudate, size and shape of pellets, PATVIS APA