ERIC Number: EJ1067315
Record Type: Journal
Publication Date: 2015-Jun
Abstractor: As Provided
Identification of Guest-Host Inclusion Complexes in the Gas Phase by Electrospray Ionization-Mass Spectrometry
Mendes, De´bora C.; Ramamurthy, Vaidhyanathan; Da Silva, Jose´ P.
Journal of Chemical Education, v92 n6 p1091-1094 Jun 2015
In this laboratory experiment, students follow a step-by-step procedure to prepare and study guest-host complexes in the gas phase using electrospray ionization-mass spectrometry (ESI-MS). Model systems are the complexes of hosts cucurbituril (CB7) and cucurbituril (CB8) with the guest 4-styrylpyridine (SP). Aqueous solutions of CB7 or CB8 with SP are infused, and full scan spectra are obtained. Students analyze the ESI-MS full scan signals and discuss the structure of the guest-host complexes based on the monoisotopic masses of hosts and guest and observed "m/z" values on the charge states and on the experimental and simulated isotope distributions. Complexes are fragmented, and spectra were obtained. The assignments are further examined taking into account the fragmentation data. The structure and gas phase reactivity of the identified supramolecular associations are discussed in view of the fragmentation patterns and host size.
Descriptors: Science Instruction, Spectroscopy, Laboratory Experiments, Science Experiments, Science Laboratories, College Science, Hands on Science, Chemistry, Scientific Concepts, Molecular Structure
Division of Chemical Education, Inc and ACS Publications Division of the American Chemical Society. 1155 Sixteenth Street NW, Washington, DC 20036. Tel: 800-227-5558; Tel: 202-872-4600; e-mail: firstname.lastname@example.org; Web site: http://pubs.acs.org/jchemeduc
Publication Type: Journal Articles; Reports - Descriptive; Guides - Classroom - Teacher
Education Level: Higher Education; Postsecondary Education
Authoring Institution: N/A