TY - JOUR
T1 - Capillary electrophoresis with electrospray ionization mass spectrometric detection for single-cell metabolomics
AU - Lapainis, Theodore
AU - Rubakhin, Stanislav S.
AU - Sweedler, Jonathan V.
PY - 2009/7/15
Y1 - 2009/7/15
N2 - A method that enables metabolomic profiling of single cells and subcellular structures is described using capillary electrophoresis coupled to electrospray ionization time-of-flight mass spectrometry. A nebulizer-free coaxial sheath-flow interface completes the circuit and provides a stable electrospray, yielding a signal with a relative standard deviation of under 5% for the total ion electro-pherogram. Detection limits are in the low nanomolar range (i.e., <50 nM (<300 amol)) for a number of cell-to-cell signaling molecules, including acetylcholine (ACh), histamine, dopamine, and serotonin. The instrument also yields high-efficiency separations, e.g., ~600 000 for eluting ACh bands. The utility of this setup for single-cell metabolomic profiling is demonstrated with identified neurons from Aplysia californica - the R2 neuron and metacerebral cell (MCC). Single-cell electropherograms are reproducible, with a large number of metabolites detected; more than 100 compounds yield signals of over 104 counts from the injection of only 0.1% of the total content from a single MCC. Expected neurotransmitters are detected within the cells (ACh in R2 and serotonin in MCC), as are compounds that have molecular masses consistent with all of the naturally occurring amino acids (except cysteine). Tandem MS using a quadrupole time-of-flight tandem mass spectrometer distinguishes ACh from isobaric compounds in the R2 neuron and demonstrates the ability of this method to characterize and identify metabolites present within single cells.
AB - A method that enables metabolomic profiling of single cells and subcellular structures is described using capillary electrophoresis coupled to electrospray ionization time-of-flight mass spectrometry. A nebulizer-free coaxial sheath-flow interface completes the circuit and provides a stable electrospray, yielding a signal with a relative standard deviation of under 5% for the total ion electro-pherogram. Detection limits are in the low nanomolar range (i.e., <50 nM (<300 amol)) for a number of cell-to-cell signaling molecules, including acetylcholine (ACh), histamine, dopamine, and serotonin. The instrument also yields high-efficiency separations, e.g., ~600 000 for eluting ACh bands. The utility of this setup for single-cell metabolomic profiling is demonstrated with identified neurons from Aplysia californica - the R2 neuron and metacerebral cell (MCC). Single-cell electropherograms are reproducible, with a large number of metabolites detected; more than 100 compounds yield signals of over 104 counts from the injection of only 0.1% of the total content from a single MCC. Expected neurotransmitters are detected within the cells (ACh in R2 and serotonin in MCC), as are compounds that have molecular masses consistent with all of the naturally occurring amino acids (except cysteine). Tandem MS using a quadrupole time-of-flight tandem mass spectrometer distinguishes ACh from isobaric compounds in the R2 neuron and demonstrates the ability of this method to characterize and identify metabolites present within single cells.
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U2 - 10.1021/ac900936g
DO - 10.1021/ac900936g
M3 - Article
C2 - 19518091
AN - SCOPUS:67650770354
SN - 0003-2700
VL - 81
SP - 5858
EP - 5864
JO - Analytical Chemistry
JF - Analytical Chemistry
IS - 14
ER -