臺灣博碩士論文加值系統

一般診間牙齒漂白多是利用30-35% H2O2高濃度的過氧化氫，配合光源或是熱進行催化達到快速牙齒漂白的效果。提高過氧化氫的濃度雖然可得到較佳的牙齒漂白效果，可是對牙髓組織的刺激性以及對牙齒本身所產生的影響及傷害也就越大。因此本實驗的目的在於尋求較佳的牙齒漂白催化劑，除了可以降低過氧化氫使用的濃度，更希望進而減低漂白過程中對牙齒的刺激及傷害。在實驗中我們選用了六種過渡金屬離子(Fe3+, Mn2+, Zn2+, Ni 2+, Cu2+, V4+)，並利用不同的載負體(Kalimate, Sodium-Y)合成金屬離子催化劑，催化低濃度的過氧化氫(10mM)，並以紫外光/可見光分光光譜儀檢測其漂白催化效果。進一步更利用Histidine合成金屬錯合物置入中孔洞分子篩(Al-MCM41)，合成中孔洞分子篩催化劑。並利用不同的實驗環境條件的調控藉以尋求最佳的漂白催化條件，同時更利用ICP-AES、TGA、EA等對金屬離子催化劑進行成份分析。在實驗結果，我們可以發現，不同的載負體所合成之金屬離子催化劑其漂白效率亦有所不同，其中以中孔洞分子篩(MCM41)最佳，Sodium-Y次之。在一般環境中Fe-Histidine@Al-MCM41和Mn-Histidine@Al-MCM41兩種金屬離子催化劑的漂白催化效果相去不遠，但在酸性環境中以Fe-Histidine@Al-MCM41的催化效果較佳，鹼性環境中則是Mn-Histidine@Al-MCM41的催化效果較佳。在過氧化氫的濃度上，我們發現當過氧化氫濃度增加時，漂白的反應速率雖然會提升，但當過氧化氫濃度高於10mM時所提升的量漸趨不明顯。利用中孔洞分子篩合成金屬離子催化劑確實能有效的催化低濃度的過氧化氫達到漂白的效果，將來或可以應用在牙齒美白治療上來升牙齒漂白速率，及降低漂白過程中牙齒的傷害！

Using light sources or heat to accelerate the bleaching of 30-35% H2O2 is getting popular for in-office bleaching. However, high-concentration H2O2 has been reported to be detrimental to tooth hard tissue as well as pulp tissue, and then post-bleaching pain ensues. The aim of this study was to search for appropriate catalysts to promote the effectiveness of tooth bleaching with low concentration of H2O2. We utilized six metal ions (Fe3+, Mn2+, Zn2+, Ni 2+, Cu2+, V4+) and Sodium-Y to catalyze the reaction rate of 10mM H2O2. Spectrophotometer was used to determine the most efficient metal ions in our established tooth stain model. The determined metal ion was anchored with Histidine and subsequently incorporated into Mesorporous-MCM41 to improve bleaching ability. The results revealed that Fe3+@Sodium-Y, had the greatest bleaching ability followed by Mn2+@Sodium-Y and orthers. Histidine can improve the catalyzing ability of metal ions and exhibit no toxic effect, while mesorporous-MCM41 can increase the reaction surface area. The Fe-Histidine@Al-MCM-41 and Mn-Histidine@Al-MCM41 complex was the most useful regimen that can promote the bleaching efficiency of H2O2.
Conclusion:By using Fe-Histidine@Al-MCM41 and Mn-Histidine@Al-MCM41 as the catalyst of H2O2, we may enhance the efficiency of tooth bleaching with less working-time, and thereby, decrease the potential damage of H2O2 to tooth during tooth bleaching.

目 錄

第一章、前言----------------------------------------------1
第二章、文獻回顧------------------------------------------2
2-1牙齒美白--------------------------------------2
2-1-1牙齒變色原因------------------------------2
2-1-2現今牙齒美白的方法------------------------6
2-1-3牙齒美白的歷史沿革------------------------6
2-1-4牙齒漂白技術對牙齒的影響------------------8
2-2牙齒美白的功臣──氫氧自由基------------------9
2-2-1氫氧自由基-------------------------------10
2-2-2氫氧自由基的產生------------------------------10
2-2-3氫氧自由基的測定------------------------------12
2-3合適的漂白催化劑-----------------------------------12
2-3-1沸石(Zeolite) --------------------------------13
2-3-2中孔洞分子篩(mesoporous molecular sieve) -----------14
2-3-3金屬觸媒的製備--------------------------------15
第三章、研究目的-----------------------------------------17
第四章、實驗藥品與儀器-----------------------------------18
第五章、材料與方法---------------------------------------24
5-1 尋找合適作為H2O2催化效率指示劑之染色劑-------------24
5-1-1 金屬離子催化劑的備製--------------------24
5-1-2 選擇適合的染色劑------------------------25
5-2 微孔洞分子篩的應用--------------------------27
5-2-1 製備Sodium-Y金屬離子催化劑-----------------------27
5-2-2 分別比較Na-Kalimate與Sodium-Y吸附不同金屬離子後的漂白催化效果-------------------------------------------------28
5-3中孔洞分子篩MCM41之應用-------------------------------29
5-3-1 利用中孔洞分子篩MCM41與微孔洞材料Sodium-Y作
為金屬載體之分析--------------------------------30
5-4 催化劑之成份分析----------------------------30
5-4-1 利用ICP-AES分析不同金屬離子催化劑中金屬-----------30
5-4-2 利用EA分析得知不同催化劑上的所吸附N/C的比例-----------------------------------------------------31
5-4-3 分析催化劑中金屬離子及Histidine的濃度及兩者間之比例-----------------------------------------------32
5-4-4 利用TGA分析催化劑之差異性--------------32
5-4-5 利用N2 adsorption-desorption isotherms 測得催化劑之表面積、孔洞大小及孔體積---------------------------32
5-5 不同控制條件下，中孔洞分子篩催化劑之催化效率---------32
5-5-1 不同的H2O2濃度下，中孔洞分子篩催化劑之催化效率
---------------------------------------------32
5-5-2 不同的pH值環境中，中孔洞催化劑之催化效率-----33
第六章、結果---------------------------------------------36
6-1 尋找合適作為H2O2催化效率指示劑之染色劑--------------36
6-1-1 染色劑Alizarin Red作為催化指示劑之效果--36
6-1-2 染色劑ß-Caretene作為催化指示劑之效果------------36
6-1-3 染色劑Phenol Red作為催化指示劑之效果----36
6-1-4 染色劑Orange(II)作為催化指示劑之效果-------------36
6-2 微孔洞分子篩之應用--------------------------37
6-2-1 分別比較Na-Kalimate與Sodium-Y吸附不同金屬離子後的漂白催化效果-------------------------------------37
6-3中孔洞分子篩MCM41之應用---------------------------37
6-3-1 利用中孔洞分子篩MCM41與微孔洞材料Sodium-Y作
為金屬載體之分析-----------------------------------------37
6-4催化劑之成份分析-----------------------------38
6-4-1 利用ICP-AES分析不同金屬離子催化劑中金屬量---------38
6-4-2 利用EA分析，得知不同催化劑上的所吸附N/C的量-------------------------------------------------------38
6-4-3 分析催化劑中金屬離子及Histidine的濃度及兩者間之比例-----------------------------------------------38
6-4-4 利用TGA分析催化劑之差異性--------------------------39
6-4-5 利用N2 adsorption-desorption isotherms 測得催化劑之表面積、孔洞大小及孔體積-----------------------------------39
6-5　不同控制條件下，中孔洞分子篩催化劑之催化效率--------39
6-5-1 不同的H2O2濃度下，中孔洞分子篩催化劑之催化效率-----39
6-5-2 不同的pH值環境中，中孔洞催化劑之催化效率-----------40
第七章、討論---------------------------------------------41
第八章、結論---------------------------------------------53
第九章、建議事項-----------------------------------------54
第十章、參考文獻-----------------------------------------55


表 次

表2-1、沸石的種類----------------------------------------65
表6-1、利用ICP-AES分析，得知金屬交換至載體上的量---------65
表 6-2 、利用EA分析，得知不同催化劑上的N/C 比例----------66
表6-3、同樣的金屬離子Fe，在不同的載負體條件下，金屬離子Fe的莫耳濃度、Histidine的莫耳濃度以及Histidine與Fe的比例-----66
表6-4、同樣的金屬離子Mn，在不同的載負體條件下，金屬離子Mn的莫耳濃度、Histidine的莫耳濃度以及Histidine與Mn的比例-----67
表6-5、利用N2 adsorption-desorption isotherms 測得催化劑之表面積、孔洞大小及孔體積---------------------------------67


圖 次

圖2-1、MCM41示意圖---------------------------------------68
圖2-2、MCM41合成-----------------------------------------68
圖4-1、Orange(II)化學結構式------------------------------69
圖4-2、Alizarin Red化學結構式----------------------------69
圖4-3、Phenol Red化學結構式------------------------------69
圖4-4、B-Carotene化學結構式------------------------------70
圖4-5、Kalimate -----------------------------------------70
圖4-6、Histidine化學結構式-------------------------------70
圖4-7、紫外光/可見光分光光譜儀---------------------------71
圖 6-1 、以染色劑Alizarin Red作為催化指示劑，配合不同金屬離子催化劑觀察其催化指示效果-------------------------------71
圖6-2、以染色劑ß-Caretene作為催化指示劑，配合不同金屬離子- 催化劑觀察其催化指示效果---------------------------72
圖6-3、以染色劑Phenol Red作為催化指示劑，配合不同金屬離子催化劑觀察其催化指示效果-----------------------------------72
圖6-4、以染色劑Orange(II)作為催化指示劑，配合不同金屬離子催
化劑觀察其催化指示效果-----------------------------------73
圖6-5A、Fe@Na-Kalimate與Fe@Sodium-Y兩種不同載體之催化劑的催化效果比較-----------------------------------------------73
圖6-5B、Mn@Na-Kalimate與Mn@Sodium-Y兩種不同載體之催化
劑的催化效果比較---------------------------------- 74
圖6-5C、Zn@Na-Kalimate與Zn@Sodium-Y兩種不同載體之催化
劑的催化效果比較-----------------------------------74
圖6-5D、Ni@Na-Kalimate與Ni@Sodium-Y兩種不同載體之催化劑
的催化效果比較--------------------------------------75
圖6-5E、Cu@Na-Kalimate與Cu@Sodium-Y兩種不同載體之催化
劑的催化效果比較------------------------------------75
圖6-5F、V@Na-Kalimate與V@Sodium-Y兩種不同載體之催化劑
的催化效果比較--------------------------------------76
圖6-6、中孔洞分子篩MCM41與微孔洞材料Sodium-Y合成之金屬離子催化劑的催化效率比較-------------------------------------77
圖6-7、Fe-Histidine@Sodium-Y之TGA圖----------------------78
圖6-8、Fe-Histidine@Al-MCM41之TGA圖----------------------79
圖6-9、Mn-Histidine@Sodium-Y之TGA圖----------------------80
圖6-10、Mn-Histidine@Al-MCM41之TGA圖---------------------81
圖6-11、不同濃度之過氧化氫條件下，中孔洞催化劑之漂白催化效果-------------------------------------------------------82
圖6-12、隨著pH值的變化，Fe-Histidine@Al-MCM41的催化效率
--------------------------------------------------82
圖6-13、隨著pH值的變化，Mn-Histidine@Al-MCM41的催化效率
--------------------------------------------------83
圖7-1、費頓反應機制--------------------------------------83
圖7-2、B-Carotene分解示意圖(Seesing & Tausch, 2004)------84

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