摘要: 以快速原子撞擊法 (FAB) 和電灑法 (ESI) 研究不同側臂索套型
冠醚2a ~ 2h與金屬離子在溶液中的錯合情形。在利用快速原子撞擊法中
，可以發現2d和Ag+有極佳的錯合能力。另外，對於Cu2+和Pb2+，此一系
列索套型冠醚也有不錯的錯合能力。 在此，我們也使用電灑法來探討會
對此一系列索套型冠醚和金屬離子錯合能力產生影響的因素，包括了溶液
的組成，負離子的種類與加入陽離子 (Rb+, Cs+) 的影響。因此，可以利
用這些因素來控制此一系列索套型冠醚和金屬離子錯合 (Li+, Na+) 的選
擇性。一般而言，2a ~ 2h對Li+有著較佳的選擇性，但若改變一些條件，
如提高水於甲醇中的比例，或添加Rb+, Cs+，則可增加其對Na+選擇性。
另外，我們也利用電灑法發展出兩種新的應用。其一為利用電灑法求出冠
醚和金屬離子錯合之穩定常數，我們也成功地求出2a ~ 2h對Li+, Na+,
K+的穩定常數。其二則是利用電灑法和冠醚與金屬離子錯合之性質，求出
溶液中的微量金屬離子含量。由此方法求出於HPLC等級的甲醇中
(Mallinckrodt) 約含有3.6 x 10-6M 的K+。

Abstract : Fast atom bombardment mass spectrometry (FAB-MS)
and electrospray mass spectrometry(ES-MS) were used to study the
complexation of various lariat crown ethers(2a ~ 2h) with metal
ions in solution.In FAB-MS, 2d has the best selectivity toward
Ag+ among others metal ions, and the simalar results was
observed in ES-MS.In addition, these lariat crown ethers have
good complexation abilities with some transition metal ions
(Cu2+ and Pb2+) as shown in FAB-MS directly. In ES-MS, factors
that influence the complexation behaviour were studied. These
factors include the solvent condition, counteranions and added
cations (Cs+, Rb+). All of these effect the experimental results
respectively. So they can be used to control ion-selectivity of
these lariat crown ethers toward Li+ or Na+.In methanol, all
these lariat crown ethers prefer to complex with Li+ as compared
with Na+and K+ ions. These sequence of selectivity is Li+>Na+>
K+. As the precentage of water increases, selectivity toward Na+
also increases. Calibration method has been developed and has
been shown to be essential in these studies. Two new
applications are developed in ES-MS. First, we used the ES-MS to
estimate the stability constants (Ks) of these lariat crown
ethers with IA metal ions (Li+, Na+ and K+). The Ks values of
these lariat crown ethers are about 105 with Li+, 104 with Na+,
and 103 with K+ in methanol. Second, we used ES-MS to detect the
trace metal ions (Na+, K+) contaminated in solutions. Even with
HPLC grade methanol ( Mallinckrodt ), 3.6 x 10-6 M of K+ were
detected.
Abstract : Fast atom bombardment mass spectrometry (FAB-MS)