title: Stability of plasma glucose during storage.
abstract: Plasma glucose concentrations were found to decrease during storage. This phenomenon was not method-dependent; it was demonstrated using both a Beckman Glucose Analyser 2 (based on glucose oxidase) and a hexokinase-based technique on a centrifugal analyser. The loss of glucose was typically of the order of 10% in plasma frozen for periods from 24 h to 14 months. Repeated freezing and thawing (weekly for 1 month) did not produce additional loss of glucose compared with aliquots thawed for the first time at 1 month. Fluoride did not reduce the loss of glucose. Glucose was also lost from frozen neutralized perchloric acid extracts of blood (mean +/- SD: 7 +/- 2 per cent over 1 year). We conclude that this variable loss of glucose on storage may complicate the interpretation of metabolic research procedures.
authors.affiliation: Sheikh Rashid Diabetes Unit, Radcliffe Infirmary, Oxford, UK.
authors.forename: M L
authors.initials: ML
authors.lastname: Clark
authors.forename: S M
authors.initials: SM
authors.lastname: Humphreys
authors.forename: K N
authors.initials: KN
authors.lastname: Frayn
mesh_terms: D001786:Blood Glucose / Q000378:metabolism*; D001793:Blood Preservation; D015925:Cryopreservation; D006801:Humans; D010472:Perchlorates / Q000494:pharmacology; D012969:Sodium Fluoride / Q000494:pharmacology
chemical_list: D001786:Blood Glucose; D010472:Perchlorates; D012969:Sodium Fluoride