title: Separation performance of cucurbit[8]uril and its coordination complex with cadmium (II) in capillary gas chromatography.
abstract: Here we report the investigation of using cucurbit[8]uril (CB8) and its coordination complex with cadmium (II) (CB8-Cd) as stationary phases for capillary gas chromatography (GC). The prepared capillary columns of CB8 and CB8-Cd stationary phases achieved column efficiency of 2200plates/m and 1508plates/m, respectively, and showed weak polarity based on the measured McReynolds constants. Their separation performance was investigated by GC separation of mixtures of different types while a commercial column was used for comparison. The CB8 stationary phase achieved high resolution for a wide range of analytes from nonpolar to polar while the CB8-Cd stationary phase exhibited good separation mainly for nonpolar to weak polar analytes. The CB stationary phases differ from the commercial one in terms of retention behaviors and resolving ability due to their different molecular interactions with analytes. Moreover, energy effect on the retention of analytes on CB8 and CB8-Cd stationary phases was examined, showing that retention on CB8 column was determined mainly by enthalpy change for polar analytes and by both enthalpy change and entropy change for weak polar analytes whereas retention on CB8-Cd column was mainly controlled by entropy change. This work demonstrates the great potential of CB8 and CB8-Cd stationary phases as a new type of GC stationary phases in GC analysis.
authors.affiliation: Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials and School of Chemistry, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Sun
authors.affiliation: Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, China.
authors.forename: Ningning
authors.initials: N
authors.lastname: Ji
authors.affiliation: Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials and School of Chemistry, Beijing Institute of Technology, Beijing 100081, China. Electronic address: mlqi2013@163.com.
authors.forename: Meiling
authors.initials: M
authors.lastname: Qi
authors.affiliation: Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, China. Electronic address: gzutao@263.net.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Tao
authors.affiliation: Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials and School of Chemistry, Beijing Institute of Technology, Beijing 100081, China.
authors.forename: Ruonong
authors.initials: R
authors.lastname: Fu
mesh_terms: D001952:Bridged-Ring Compounds / Q000302:isolation & purification*; D002104:Cadmium / Q000737:chemistry*; D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods*; D019277:Entropy; D007093:Imidazoles / Q000302:isolation & purification*; D008855:Microscopy, Electron, Scanning; D015203:Reproducibility of Results; D013816:Thermodynamics; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
chemical_list: D001952:Bridged-Ring Compounds; D002104:Cadmium; D007093:Imidazoles; C507198:cucurbit(8)uril; D047028:Macrocyclic Compounds; D000099246:Cucurbit(n)urils
keywords: Capillary gas chromatography; Coordination complex; Cucurbit[8]uril; Stationary phase