A Series of Nested GC-MS Applications in the Introductory Chemistry Sequence

本项目设计了一套嵌套或相互关联的实验，采用气相色谱-质谱（GC-MS）作为一种技术，使学生能够在不断增加的复杂水平上使用这种多功能仪器。因为目的是结合GC-MS在入门一般和有机化学实验室序列，一个仪器密集的研究样的经验已经设计了每个实验室序列围绕跨学科的主题：一般化学实验室的环境化学（分析人工“汽油”混合物，然后分析被汽油和/或杀虫剂污染的水和土壤）和有机化学实验室的植物实验（使用学生合成的标准对植物提取物进行脂肪酸、甲酯分析，以及一系列植物生长激素的合成、鉴定和表征）。以这种方式设计每个项目的假设是，学生通过一系列连续的应用程序充分掌握气相色谱-质谱，并接触现代仪器，特别是以动手的形式，是非常可取的。这些项目的主题基础与地球科学和生物学的相关学科建立了联系。许多有抱负的预科生如果不修地质学课程，也会修生物学，因此桥接实验室的概念可以帮助这些学生从几个学科的角度来看待他们的实验室工作的相关性。在普通化学和有机化学实验室序列中，通过将具有分离和鉴定双重功能的气相色谱-质谱相结合，增强了“合成-结构-鉴定”的组织范式。

This project designs a set of nested or interrelated experiments employing gas chromatography-mass spectrometry (GC-MS) as a technique that exposes students to the use of this versatile instrument at ever-increasing levels of sophistication. Because the intent is to incorporate GC-MS in the introductory general and organic chemistry laboratory sequences, an instrument-intensive research-like experience has been designed for each laboratory sequence around an interdisciplinary theme: Environmental Chemistry for the general chemistry laboratory (analysis of an artificial "gasoline" mixture followed by water and soil analyses contaminated with gasoline and/or pesticides) and Plant Assays for the organic chemistry laboratory (a fatty acid, methyl ester analysis of a plant extract using standards synthesized by the students and synthesis, identification, and characterization of a series of plant growth hormones). The assumption in designing each project in this manner is that students gain sufficient mastery in GC-MS by a sequential series of applications and that exposure to modern instrumentation, especially in a hands-on format, is highly desirable. The thematic basis for the projects creates links with the related disciplines of geosciences and biology. Many aspiring premeds take biology, if not geology courses, so the bridging laboratory concept helps those students see the relevance of their laboratory work from several disciplinary perspectives. In both the general and organic chemistry laboratory sequences, the organizational paradigm of "Synthesis, Structure, and Identification" is enhanced by the integration of the GC-MS with its dual capability of separation and identification.