碩士 / 國立高雄應用科技大學 / 化學工程與材料工程系博碩士班 / 106 / Abstract
Phycobiliproteins are commonly found in blue-green algae and red algae, and are mainly including C-phycocyanin (C-PC), allophycocyanin (APC), and R-phycoerythrin (R-PE). Owing to their distinguished spectroscopic properties, phycobiliproteins have a wide range of application, such as therapeutic reagents, fluorescent immunoprobes, and health foods. Purification of phycobiliproteins usually involves complex and time-consuming operations, resulting in low recovery. Therefore, there is a need to develop a simple and effective method for separating and purifying C-PC and APC from high-purity cyanobacteria. This study proposes the use of polyethylenimine (PEI) modified Hydroxyapatite as an adsorbent to adsorb C-PC and APC, and discusses the preparation method, adsorption model and the adsorption capacity. Hydroxyapatite (HAp) can be prepared from egg shells and has been widely used for drug release, gene delivery, wastewater treatment, and protein and nucleic acid separation and purification. The composition of Ca2+, PO43-, and OH- in the hydroxyapatite structure provides positive and negative charges for electrostatic adsorption. The modification of HAp with polyethyleneimine can increase the density of positive charges. Up to now, although there are many literatures on the purification of phycobiliproteins, there have been no studies on the preparation of polyethyleneimine modified hydroxyapatite composites for C-phycocyanin and allophycocyanin adsorption. In this study, hydroxyapatite was obtained by calcining the eggshell at 900°C and then reacting with dipotassium hydrogen phosphate. The PEI modified hydroxyapatite (HAp-PEI) was characterized by transmission electron microscope (TEM) to observe its surface morphology, and Fourier Transform Infrared Spectrometer (FTIR) the surface modification of PEI on the hydroxyapatite, and the weight of PEI grafts was confirmed by thermal weight loss analyzer (TGA). For the application of adsorption recovery, HAp-PEI was added to pH 5 C-PC and pH 6 APC solution for adsorption, and then the protein was desorbed with pH 8 buffer solution. It was found that the adsorption capacity of HAp-PEI toward C-PC and APC was higher than that of HAp particles. The results showed that the adsorption capacity of HAp to proteins can be improved by PEI modification. The maximum adsorption capacity for C-PC is 106.5 mg C-PC/g particles at pH 5, and for APC is 666.6 mg APC/g particles at pH 6. The adsorption of HAp-PEI toward C-PC and APC accorded with the pseudo second-order kinetics model, indicating the adsorption mechanism is dominated by chemical adsorption.The adsorption experiment data showed that the adsorption behavior of HAp-PEI on C-PC and APC conformed to the Langmuir isotherm. The adsorption model shows monolayer adsorption. It shows that the application of HAp in phycobiliprotein purification is feasible.
| Identifer | oai:union.ndltd.org:TW/106KUAS0063040 |
| Date | January 2018 |
| Creators | Chang, Yu-Pei, 張鈺培 |
| Contributors | Chen, Shu-Jen, 陳樹人 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 87 |
Page generated in 0.0024 seconds