Surface and modification of LP-SBA-15 with polyethyleneimine for celecoxib delivery


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye

Tezin Onay Tarihi: 2017

Öğrenci: ALI FARID

Eş Danışman: AYŞEN YILMAZ, SREEPARNA BANERJEE

Özet:

In this study LP-SBA-15 (LP stands for large pores) and LP-SBA-15-PEI (PEI stands for polyethyleneimine), ordered mesoporous silica support material utilized with different pore structure characteristics to investigate on their drug delivery system abilities like release and loading properties, regarding to their structural variability and implication of surface modification. Hydrothermal synthesis method was used for synthesis of LP-SBA-15 and surface functionalization was done by polymerization of hyperbranched polyethyleneimine inside pores. The referred functional group expected to interact with surface silanols on the silica supports, and this interaction expected to be enriched by introduction of amino groups to the silica surfaces. For organic modification, necessities of larger pore mesophases is obvious. Since, accessibility of pore is highly dependent on pore size and structure. Therefore, having larger pores provides higher chance to have large empty spaces inside pores, even after modification of pores. After functionalization, drug loading was carried out in ethanol. As a drug model, Celecoxib (CLX) was used for investigation on bioavailability and drug delivery systems characterizations which is nonsteroidal anti-inflammatory drug that shows highly hydrophobic quality and also has very low bioavailability. Effect of particle morphology and specific pH was analyzed on release properties and release experiment was done in two different pH (pH= 5.0 and pH= 7.4). In characterization part, LP-SBA-15 particles were characterized by using X-ray Diffraction (XRD), Small-Angle X-ray Spectrometry (SAXS), N2 adsorption - desorption, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Ultra-Violet Spectrometry (UV-VIS) and Thermogravimetric Analysis (TGA). Hence, several characterizations were applied for better understanding the bioavailability, morphology, crystallinity etc. Consequently, an enhanced release rate on drug delivery properties were observed for LP-SBA-15-PEI in comparison to commercial drug and non-polymerized sample. More specifically, 41% of loading for LP-SBA-15-CLX and 25% for LP-SBA-15-PEI were observed. Moreover, more than 80% release in both pH= 5.0 and pH= 7.4 for LP-SBA-15-PEI-CLX and less than 50% in case of LP-SBA-15-CLX were exhibited. Which introduces LP-SBA-15-PEI as a proper choice for drug delivery systems since the release percent of Celebrex itself were less than 60% in both cases.