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.
Department of Chemistry, Purdue University, West Lafayette, IN 47907, United States.
Ravi
R
Kc
Yashas N
YN
Gowda
Danijel
D
Djukovic
Ian D
ID
Henry
Gregory H J
GH
Park
Daniel
D
Raftery
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