巨環多胺化合物或其與金奈米自組裝鍵結相管柱在生化分析上的應用

Macrocyclic Polyamine Bonded Phase and Gold Nanoparticles Self-assembled Column for Bioanalytical Applications

陳澤賢(Tse-Hsien Chen)

指導教授 ： 劉春櫻

國立臺灣大學/理學院/化學研究所/博士(2007年)

https://doi.org/10.6342/NTU.2007.01509

摘要

本研究以3-glycidoxypropyl-trimethoxysilane將毛細管矽烷化後，分別將32環([32]ane-N8) 及28環([28]ane-N6O2) 之巨環多胺分子鍵結於管壁，所製備管柱以苯甲醇為標的物量測其電滲流(EOF)，發現pH 3 ~ 8條件下32環鍵結管柱之EOF較28環者為低，如於pH 4下其μeo分別為 -6.19 × 10-4及-9.67 × 10-4 cm2V-1s-1。若於管柱製備過程中加入pyridine，則毛細管壁靜相之鍵結量增加，所製備之32環管柱其電滲流於pH 6時由原先μeo為 -1.31 × 10-4 cm2V-1s-1增加約3倍。本研究第一部份先以含硫胺基酸及胜肽為模式分析物來探討所製備毛細管柱之層析行為，並探討注入樣品的酸鹼度對管柱分離行為的影響。以100 mM、pH 4.00之醋酸為動相，電場強度為-200 V/cm之條件下注入鹼性樣品溶液(pH 7.76) 可達基線分離，且此系統可成功應用於複雜基質如尿液中glutathione之分析。然而28環鍵結相管柱卻無法有效分離氧化及還原態glutathione，顯示巨環效應對辨識分子的影響。若動相改以醋酸緩衝液並以pH梯度方式進行，則可成功分離酸性樣品溶液(pH 2.73)，樣品之pH若為1.89則需進一步使用pH梯度且動相加入乙醇才能完全分離。
本研究進而以32環管柱來探討其對胜肽之辨認行為，9種胜肽分子包括angiotensin (I、II及ST)、β-casomorphin (bovine及human)、oxytocin acetate、tocinoic acid、vasopressin及FMRF amide等均可完全辨識，再現性(RSD < 1 %) 和平均理論板數(10-5 m-1) 也都顯示其對生化或醫學方面應用的潛力，分離機制涉及電泳遷移、靜電作用、氫鍵及巨環效應等。為探討所製備管柱之穩定性，於注射樣品600次後，其pH 7之μeo由原先之9.14 × 10-5 cm2V-1s-1 提高為 9.68 × 10-5 cm2V-1s-1 (n = 6)，亦即增加5.91 %。進一步發現所鍵結32環分子受器管柱尚可辨認[Leu5]-enkephalin及[Met5]-enkephalin兩種腦啡肽分子，若使用pH梯度法，可使分析時間由30分鐘縮短為18分鐘。本研究續以還原性胺化作用將醣類分子製備成p-aminobenzoic acid之衍生物，以螢光偵測(激發波長313 nm，放射波長358 nm) 及配合濃度梯度法可成功分離8種醣類分子，其中包含單醣及雙醣的差向異構體，分離機制主要藉由硼酸及衍生試劑與分析物作用之產物和巨環的配位作用。
本研究亦藉由(3-mercaptopropyl)trimethoxysilane之硫醇基將金奈米粒子(Au NPs) 自組裝於毛細管壁以分離含硫生化分子，由研究發現高濃度之背景電解質(80 ~ 120 mM) 可避免氣泡產生。若將分析物配製成鹼性，動相使用pH 4、80 mM之醋酸緩衝液，電場強度為200 V/cm可得最佳分離結果，滯留次序顯示其機制主要以配位基交換為主。由巨環多胺分子與Au NPs作用之UV光譜，發現Au NPs與[32]ane-N8作用時，光譜由具最大520 nm之吸收峰轉變為範圍為500 ~ 650 nm的吸收寬帶，顯示有聚合體(aggregates) 產生且可穩定存在。由反應時間之光譜變化，發現因[28]ane-N6O2之正電荷較[32]ane-N8為少，故形成聚合體之速率較慢。本研究將Au NPs自組裝於32環管柱，發現此管柱不僅對含硫分子具備很好的分離效率，且可分離ovalbumin、apo-transferrin及serum albumin等蛋白質，其中ovalbumin尚可獲得6支吸收峰，顯示其對醣蛋白之同分異構物的高分離能力。

關鍵字

巨環多胺化合物 ； 金奈米粒子 ； 毛細管電層析

並列摘要

Two macrocyclic polyamines, [32]ane-N8 and [28]ane-N6O2 were prepared and employed as a selective modifier for the capillary electrochromatographic separation. Under the same coating process, it has been observed that [28]ane-N6O2 coated column showed higher electroosmotic flow (e.g. μeo = -9.67 × 10-4 cm2V-1s-1) than that of [32]ane-N8 (μeo = -6.19 × 10-4 cm2V-1s-1) at pH 4. It is noteworthy to mention that μeo values increase if pyridine is added into the solution of coating process. As for example, μeo increases from -1.31 × 10-4 to -4.43 × 10-4 cm2V-1s-1 at pH 6, indicating that a greater amount of the bonded ligands were found with the addition of pyridine. With [32]ane-N8 coated column, the optimum conditions for the separation of aminothiols were at -20 kV using an acetate buffer (30 mM, pH 4.0), hydrodynamic injection and detection wavelength at 214 nm. A basic mixture (pH 7.76) of sulfur-containing biomolecules was baseline separated in less than 15 min. In the similar experimental conditions, the [28]ane-N6O2 coated capillary column showed only five peaks and no characteristic splitting for reduced and oxidized form of glutathione. With pH gradient mode, the baseline separation of the acidic mixture (pH 2.73) was demonstrated using an acetate buffer (30 mM) with inlet buffer pH 4 and outlet buffer pH 3 (pH 4-3). But ethanol was needed in the mobile phase for the separation of acidic mixture (pH 1.89).
A mixture of angiotensin (I、II and ST)、β-casomorphin (bovine and human)、oxytocin acetate、tocinoic acid、vasopressin and FMRF amide could be separated using phosphate buffer (pH 7, 30 mM). Column efficiency was found with the average theoretical plate numbers of 70000 m-1 and relative standard deviation (RSD) of < 1 % (n = 6) The prepared column can be used with injections more than 600 with the EOF increase only 5.91 %. [Met5]-enkephalin and [Leu5]-enkephalin could also be separated with the bonded phase in 30 mM acetate using pH gradient method (pH 4-3). The [32]ane-N8 coated column was also applied to separate of mono- and disaccharides. The reductive aminated product was carried out with p-aminobenzoic acid. A synergic effect was observed for the separation of borate complexes with the bonded phase. A complete separation of all compounds as well as the excess derivatizing agent by using borate buffer (pH 9.0) in a mode of concentration gradient (60 mM inlet side and 70 mM outlet side) could be achieved. The RSD of the migration time measured for each sample was less than 4 % in six continuous runs, suggesting that the bonded phase along with the gradient formed inside the column was quite stable. The results indicated that with the mixing modes of anion coordination, anion exchange, and shape discrimination, the interaction adequately accomplishes the separation of carbohydrates which are epimers or have different glycosidic linkage, although the electrophoretic migration is also involved in the separation mechanism.
The gold nanoparticles(Au NPs) was immobilized in fused-silica capillary column wall by (3-mercaptopropyl)trimethoxysilane for the separation of sulfur-containing biomolecules. We used high concentration buffer (80 ~ 120 mM) to avoid bubble formation. Baseline separation of basic mixture was obtained at 20 kV, using an acetate buffer (80 mM, pH 4). The results suggested that the interaction between analytes and the bonded groups on the wall is ligand exchange. The Au NPs solutions were added into both 32- and 28-membered macrocyclic polyamines for realizing the status of NPs in the presence of these ligands. Spectral changes and TEM pictures demonstrate that the macrocyclic polyamines, which possess positive charges, trigger aggregation of negatively charged citrate-capped nanoparticles. Then the Au NPs self-assembled in a [32]ane-N8 coated column wall. The good separation efficiency was procured not only sulfur-containing biomolecules but also proteins include six ovalbumin peaks are observed.

並列關鍵字

macrocyclic polyamine ； gold nanoparticles ； capillary electrochromatography

參考文獻

3. Consden, R., A. H. Gordon, A. J. P. Martin, Biochem. J. 1944, 38, 224-232.

76. Misra, T. K., Chen, T. S., Wong, K. T., Liu, C. Y., J. Chin. Chem. Soc. 2005, 52, 793-797.

55. Guan, N., Zeng, Z. R., Wang, Y. C., Fu, E. Q., Cheng, J. K., Anal. Chim. Acta 2000, 418, 145-151.

56. Wang, Y. C., Zeng, Z. R., Xie, C. H., Guang, N., Fu, E. Q., Cheng, J. K., Chromatographia 2001, 54, 475-479.

48. Wang, Y. C., Zeng, Z. R., Xie, C. H., Guan, N., Fu, E. Q., Cheng, J. K., Chromatographia 2001, 54, 475-479.