Susceptibility-matched plugs for microcoil NMR probes.
For mass-limited samples, the residual sample volume outside the detection coil is an important concern, as is good base line resolution. Here, we present the construction and evaluation of magnetic susceptibility-matched plugs for microcoil NMR sample cells which address these issues. Mixed-epoxy glue and ultem tube plugs that have susceptibility values close to those of perfluorocarbon FC-43 (fluorinert) and copper were used in small volume (0.5-2 microL) and larger volume (15-20 microL) thin glass capillary sample cells. Using these plugs, the sample volume efficiency (i.e. ratio of active volume to total sample volume in the microcoil NMR cell) was improved by 6-12-fold without sensitivity and resolution trade-offs. Comparison with laser etched or heat etched microcoil sample cells is provided. The approaches described are potentially useful in metabolomics for biomarkers detection in mass limited biological samples.
Kc
Ravi
R
Department of Chemistry, Purdue University, West Lafayette, IN 47907, United States.
Gowda
Yashas N
YN
Djukovic
Danijel
D
Henry
Ian D
ID
Park
Gregory H J
GH
Raftery
Daniel
D
D001774:Blood Chemical Analysis / Q000295:instrumentation; D003300:Copper / Q000737:chemistry; D004581:Electronics; D004852:Epoxy Compounds; D004867:Equipment Design; D005466:Fluorocarbons; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation*; D055432:Metabolomics; D016482:Urinalysis / Q000295:instrumentation
D004852:Epoxy Compounds; D005466:Fluorocarbons; C429307:fluorocarbon 77; D003300:Copper