Detection Technique – MS,Detection Technique – NMR

Detection Technique – MS

n  To identify and to quantify metabolites

n  Serves to both separate and to detect

n  Mass to charge ratios

n  Using electron beam

n  Ion source, mass analyzer and detector

Detection Technique – NMR

n  A typical 950-MHz H NMR spectrum of urine showing the degree of spectral complexity\

Comparison

	NMR	GC-MS	DI-MS
Sample prep time	30 -120 min/20 samples	30 -120 min/20 samples	3-4 h for 96 samples
Run time	20 -90 min/sample	30-60 min/sample	7 min/sample
Data Analysis	30-60 min / sample	30-60 min / sample	1-2 h for 96 samples
Limit of Detection	~ 5 µM	~ 100 nM	~ 5 nM
No. of metabolites	~ 20 - 50	~20 -50	~ 100-180
Overlapping Metabolites	10-15	10-15	10-15
Cross-checking	10-30 %	10-30 %	10-30 %

	NMR (with cold probe)	GC-MS	DI-MS
Metabolites	Water-soluble (amino acids, organic acids, sugars)	mainly water-soluble (some hydrophobic)	Mainly hydrophobic (some water-soluble)
Types of samples	Biofluids, plant, bacterial, animal tissue extracts, Food	Biofluids, plant, bacterial, animal tissue extracts, Food	Mainly biofluids
Sample Volume	100 µL (min)	30-50 µL (min)	10 µL

Run time	20 -90 min/sample	30-60 min/sample	7 min/sample
Data Analysis	30-60 min / sample	30-60 min / sample	1-2 h for 96 samples
Limit of Detection	~ 5 µM	~ 100 nM	~ 5 nM
No. of metabolites	~ 20 - 50	~20 -50	~ 100-180
Overlapping Metabolites	10-15	10-15	10-15
Cross-checking	10-30 %	10-30 %	10-30 %