互穿金屬有機框架之微小化及功能化並應用於癌症的光熱—放射聯合療法

Abstract

近年來，孔洞材料用於生醫領域的潛力逐漸受到重視，本論文探討了兩類新興孔洞材料的開發、合成、鑑定，並且將它們應用於癌症治療、骨折治療，以及鼻腔藥物輸送。

其中，在本論文第一、二章節中探討了鋯基/鉿基金屬有機框架Zr/Hf-PEB的製備，並且透過配位調控的策略，在不破壞結晶性的情況下，將這兩種互穿結構之金屬有機框架之粒徑縮小至約200奈米，適合用於生醫領域。接著，利用了Hf-PEB配位體上三鍵的特性，將鈀金屬奈米顆粒嵌入到Hf-PEB的孔洞之中。考量到鉿元素具有高原子序，可以做為癌症放射治療的增敏劑，並且鈀金屬奈米顆粒可以吸收近紅外光的特性，可作為光熱治療的增敏劑，因此，包覆了鈀金屬奈米顆粒的鉿基金屬有機框架Pd@Hf-PEB可以被應用在癌症的光熱-放射聯合療法中。

而本論文的第三章節探討了鐵基金屬有機框架 MIL-100(Fe) 材料的合成以及修飾，並將其作為鎂離子的載體，應用於骨頭的修復。由於鎂離子的直徑小於MIL-100(Fe) 孔洞的窗口大小，因此在鎂離子被載入MIL-100(Fe) 的孔洞之中後，需要進行表面修飾，使得鎂離子能夠停留於孔洞之中，對此，本研究提出了兩個策略：1. 將聚丙烯酸的鈉鹽修飾到搭載鎂離子之MIL-100(Fe) 之表面。 2. 將聚丙烯酸透過EDC/NHS反應修飾到搭載鎂離子之NH2-MIL-100(Fe) 表面，據我們所知，NH2-MIL-100(Fe) 是由我們團隊最先發表之材料，是帶有NH2官能基版本的MIL-100(Fe) 金屬有機框架，先前我們已展示其在修飾後，可以被應用在蛋白質的純化。在這個研究中，元素分析的結果表明第一種聚丙烯酸修飾方式更能夠提升鎂離子的搭載量，並且，將其與MG-63骨肉瘤細胞株共培養時，可以在初期提升細胞鹼性磷酸酶的活性，顯示搭載鎂離子的MIL-100(Fe) 具有加速骨細胞分化的特性。

而本論文的第四章節則是關於鼻腔乾粉疫苗劑型的開發，透過薄膜冷凍技術以及凍乾製程，液體疫苗可以被轉化為具高度孔洞性，適合透過鼻腔輸送的乾粉劑型，在研究中，我們合成了含有微脂體佐劑的模式疫苗，並且發現添加羧甲基纖維素可以提升疫苗粉末對黏膜的黏附性，當使用鼻噴劑系統將疫苗粉末輸送到鼻腔模型時，粉末可以抵達鼻甲以及鼻咽區域，顯示此疫苗粉末搭配鼻噴劑系統的有效性。

在第五章節中，薄膜冷凍技術以及凍乾製程被用來將中和SARS-CoV-2的單株抗體轉化為乾粉劑型。此劑型不僅具有高度孔洞性，且其中的單株抗體並不會在冷凍乾燥的過程中大量團聚，適合被輸送至鼻腔之中，以及用於預防或治療上呼吸道的病毒感染。同樣的，當使用鼻噴劑系統將疫苗粉末輸送到鼻腔模型時，此單株抗體粉末劑型可以抵達鼻甲以及鼻咽區域。

總的來說，這些章節皆探討了新穎孔洞材料的開發，以及於生醫領域的應用潛力，並且範圍涵蓋了癌症治療、骨治療，疫苗的輸送，以及病毒的預防及治療。

In recent years, the potential of porous materials as biomedical materials has gained attention. This dissertation explores the development, synthesis, and characterization of two kinds of porous materials (i.e., metal-organic frameworks and thin-film freeze-dried powders), and their applications in cancer therapy, bone healing, and intranasal drug delivery.

In Chapter 1 and Chapter 2, the synthesis of interpenetrated Zr or Hf-based metal-organic frameworks (MOFs) (Zr-PEB or Hf-PEB) was studied. Since methods that could produce nanoscale Zr-PEB or Hf-PEB have not been reported, coordination modulation strategy was tuned to reduce their sizes to about 200 nm for the first time, making them suitable for biomedical applications. The ethynyl group on the linker of Hf-PEB has been utilized to incorporate Pd nanoparticles into the pores. Considering that Hf, as a high-Z element, can sensitize X-ray during radiotherapy, and Pd nanoparticles can sensitize near-infrared (NIR) during photothermal therapy, the Pd-loaded Hf-PEB (Pd@Hf-PEB) can be applied in the combined photothermal-radiation therapy of cancer.

In Chapter 3, the synthesis and surface modification of the iron-based MOF MIL-100(Fe) was studied, and Mg ions were loaded to the pores of MIL-100(Fe) for bone healing. Since the diameter of Mg ions is smaller than the window size of MIL-100(Fe), a surface modification is required to improve the loading of Mg ions. Two strategies were utilized in this study: 1. Grafting the surface of Mg-loaded MIL-100(Fe) with the sodium salt of poly(acrylic acid). 2. Functionalizing the surface of Mg-loaded NH2-MIL-100(Fe) with poly(acrylic acid) via EDC/NHS reaction. Where NH2-MIL-100(Fe) is MIL-100(Fe) with a NH2 substitution group on the linker. To the best of our knowledge, NH2-MIL-100(Fe) was reported by our group for the first time, and previously we have demonstrated that NH2-MIL-100(Fe) after surface modification can be utilized in the purification of proteins. The results show that the material produced using the first strategy (i.e., Mg@MIL-100(Fe)-PAA) had a higher Mg loading. When osteosarcoma cells MG-63 were treated with Mg@MIL-100(Fe)-PAA, the alkaline phosphatase (ALP) activity increased in the first few days, indicating that Mg@MIL-100(Fe)-PAA can potentially promote osteoblast differentiation and accelerate bone healing.

In Chapter 4, the development of a nasal powder vaccine formulation was study. By utilizing the thin-film freezing (TFF) technology and lyophilization, liquid vaccines can be converted into porous dry powder vaccines suitable for intranasal delivery. Therefore, a model vaccine containing liposomal adjuvant and ovalbumin as antigen was synthesized. It was found that the addition of sodium carboxymethyl cellulose (CMC) can enhance the powder's mucoadhesion property. When the vaccine powder was delivered to the nasal replica casts using a nasal spray system from Aptar, it reached the turbinates and nasopharyngeal regions, demonstrating the efficacy.

In Chapter 5, again, TFF technology and lyophilization were used to convert a monoclonal antibody (mAb) neutralizing SARS-CoV-2 into dry powder formulations without causing significant aggregation of the mAb. Similarly, when delivered to nasal replica casts using Aptar’s nasal spray system, the mAb powder could reach the turbinate region and nasopharynx, indicating that the powder is suitable for intranasal delivery to prevent or treat upper respiratory infections

Overall, this dissertation focusses on the development of novel (porous) materials and their potential biomedical applications, including cancer therapy, bone healing, intranasal vaccine, and viral infection prevention and treatment.