基質輔助雷射脫附游離飛行時間質譜法和拉曼光譜技術於茜素媒染色澱成分鑑定及結構解析之研究

Abstract

本研究使用基質輔助雷射脫附游離飛行時間質譜法和拉曼光譜技術，探討茜素與媒染劑（包括醋酸鋁，硫酸鋁鉀，醋酸鋁與醋酸鐵）反應時，形成「茜素-金屬離子」有機金屬錯合物的可能結構。此反應一旦形成有機金屬錯合物，其沉澱物的顏色分佈為紅色到褐色。該沉澱物可使用基質輔助雷射脫附飛行時間型質譜儀加以測量，並以CHCA (alpha-cyano-4-hydroxycinnamic acid)作為基質。實驗結果發現在正電模式時，質譜圖上有一明顯的訊號在m/z=504.043，符合兩個茜素分子與醋酸鋁中的鋁離子錯合的荷質比。此外在測量茜素與明礬溶液的訊號時，還偵測到了茜素與鋁離子和鉀離子的中間產物之訊號在m/z=316.049、m/z=331.069、m/z=375.075、m/z=392.082，符合茜素分子與鋁離子和鉀離子錯合時配位了羥基和甲氧基的荷質比。利用拉曼光譜觀察到特徵峰值分別為1298 cm-1、1332 cm-1、1454 cm-1、1480 cm-1代表了C-OH和C-H的彎曲振動，以及C-C的伸縮振動，還觀察到了1630 cm-1 的C=O伸縮振動和1162 cm-1及1193 cm-1的 C-H彎曲振動和C-C的伸縮振動，基於這些特徵峰值最後推測出化學結構，並比對文獻參考進行驗證。為了探討媒染後的顏色變化，利用LabVIEW程式中RGB數值轉換為波長的程式，探討該方法取代反射式吸收光譜法的可行性。

Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) and Raman spectroscopy techniques were used to investigate the potential structures of"Alizarin -Metal Ion" organic-metal complexes formed during the reaction between alizarin and mordants (including aluminum acetate and alum). Once these organic-metal complexes are formed, the precipitate exhibits a color range from red to brown. The precipitate can be measured using MALDI-TOF MS with CHCA (alpha-cyano-4-hydroxycinnamic acid ) as the matrix. Experimental results revealed a prominent signal at m/z=504.043 in positive ion mode on the mass spectrum, matching the mass-to-charge ratio of two alizarin molecules complexed with aluminum ions in aluminum acetate. Furthermore, when measuring signals from the alizarin and alum solution, intermediate products of alizarin with aluminum and potassium ions were detected at m/z=316.049, m/z=331.069, m/z=375.075, and m/z=392.082, corresponding to the mass- to-charge ratios expected when alizarin molecules coordinate with hydroxyl and methoxy groups in aluminum and potassium ions.Using Raman spectroscopy, characteristic peaks at 1298 cm-1, 1332 cm-1, 1454 cm-1, and 1480 cm-1 were observed, representing the bending vibrations of C-OH and C-H, as well as t he stretching vibrations of C-C. Additionally, peaks at 1630 cm-1 for C=O stretching vibration and 1162 cm-1 and 1193 cm-1 for C-H bending vibration and C-C stretching vibration were observed. Based on these characteristic peaks, the chemical structure was inferred and validated against literature references.In order to explore the color changes after mordant dyeing, the program for converting RGB values into wavelengths in the LabVIEW program was used to explore the feasibility of this method instead of reflection absorption spectroscopy