- 學位論文
運用旋轉磁場於磁性奈米粒子吸附牛血清白蛋白之研究
Study of Adsorption of Bovine Serum Albumin on Magnetic Nanoparticles with Rotating Magnetic Field
摘要
本研究目的為探討牛血清白蛋白與磁性奈米粒子，於微量環境並施予外加旋轉磁場之吸附效果。研究主軸是設計製備一套旋轉磁場微量反應系統，以未經由改質之磁性奈米粒子，整合至自製之微量反應裝置中，施予外加旋轉磁場產生擾動，透過電性吸附與粒子結構等物理方式使蛋白質吸附至磁性奈米粒子上，探討磁場大小與轉速對吸附之影響。磁性奈米粒子運用共沉澱法合成四氧化三鐵奈米粒子，以紅外線傅立葉轉換紅外光光譜儀（FT-IR）驗證官能基；介面電位量測儀（Zeta potential）測定表面帶電荷；SQUID 測定飽和磁化量；最後以TEM測定其形態，粒徑大小為20± 5 nm。測試合成之磁性奈米粒子前測試吸附效率，於pH 5時有最好吸附效率，亦透過FT-IR與TEM影像再次驗證。旋轉磁場系統之架設運用3D列印技術製作成品，磁場大小可透過改變磁鐵距離調控，旋轉轉速可透過電壓線性調控。微量反應裝置則運用留置針及微量吸管頭組合完成。將磁性奈米粒子結合微量反應裝置，置於旋轉磁場中進行實驗，實驗參數設定為1 mg磁性奈米粒子、濃度1 mg/ml牛血清白蛋白、體積量100 l。結果顯示磁性奈米粒子於微量反應裝置中，當轉速越快、磁場越大時，磁性奈米粒子受到溶液粘滯力遠大於磁偶極力，使磁性奈米粒子無法維持鏈狀而分散於溶液中，因此與蛋白質溶液接觸面積增加，進而得到更好的吸附效果。實驗結果將磁場強度1500 Gs、旋轉速度800 rpm，定為目前最佳之吸附參數，吸附30 min後可達70 mg/g之吸附量。並進一步探討其吸附動力學以及吸附等溫線；經由計算符合偽二階吸附動力學模型，R2值為0.99042、吸附速率常數k2值為0.11544 g/mg/min。吸附等溫線則符合Langmuir等溫吸附方程式，R2為：0.99033，吸附常數K為57.34。透過重複吸附可有效縮短吸附時間及提升吸附效率，第一次吸附量為35 mg/g、第二次吸附提升至65 mg/g、第三次吸附在提升至接近80 mg/g，有效縮短6倍時間。於pH 11、1 M之磷酸氫二鈉溶液可有效將蛋白質脫附，去吸附效率可達98%。本研究顯示旋轉磁場大小、轉速會影響磁性奈米粒子與蛋白質之接觸面積與吸附效率，於高磁場、高轉速有更好之吸附效果。
並列摘要
The goal of this study is to investigate the adsorption effect of bovine serum albumin (BSA) and magnetic nanoparticles in the A micro-capacity reactor with rotating magnetic field. During BSA protein adsorption study, non-modified magnetic nanoparticles were loaded into micro-capacity device, an external rotating magnetic field were than applied. Magnetic nanoparticles (MNPs) were prepared by chemical co-precipitation. Characterizations of magnetic nanoparticles were carried out using Fourier-transform infrared spectroscopy (FTIR), which confirmed the components of magnetic nanoparticles. The Zeta potential was used to measure surface charge of MNPs which is slightly negative. Superconducting quantum interference device (SQUID) was used to confirm saturation magnetization. Size and morphology of magnetic nanoparticles were characterized by Transmission electron microscopy (TEM). The size of magnetic nanoparticles is about 20±5 nm. The adsorption efficiency of the synthesized magnetic nanoparticles was tested for the most adsorption amount and the adsorption efficiency at pH 5, which was also verified by FT-IR and TEM images. The homemade rotating magnetic system set up by 3D printing technology. The magnetic field can be achieved by adjusting the magnet distance. The rotation speed can be linearly controlled by voltage. The micro-capacity reactor device was made by retention needle components and micro-suction tip. The experimental parameters were set to 1 mg of magnetic nanoparticles at a concentration of 1 mg / ml bovine serum albumin in a volume of 100 μl. The results show that in different magnetic field and rotating speed, magnetic nanoparticles have different arrangement. In 1500 Gs, 800 rpm has the best adsorption amount in our setting parameters, adsorption in 5 min, up to 35 mg / g, adsorption to 30 min, up to almost 70 mg / g. The adsorption kinetic is fitted the pseudo-second order model (R2=0.99042). The corresponding rate parameter is 0.11544 g/mg/min. The adsorption equilibrium isotherm was fitted well by the Langmuir model (R2=0.99033) with K value was 57.34. By repeated adsorption we effectively shorten the adsorption time to enhance the adsorption efficiency. At pH 11.1 M, the disodium hydrogen phosphate solution can effectively desorb the protein, the desorption ratio almost up to 100%.