scholarly journals Changes in intracellular Mg adenosine triphosphate and ionized Mg2+ during blood storage: detection by 31P nuclear magnetic resonance spectroscopy

Blood ◽  
1985 ◽  
Vol 65 (6) ◽  
pp. 1526-1530 ◽  
Author(s):  
JL Bock ◽  
B Wenz ◽  
RK Gupta
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Adenosine Triphosphate ◽  
Resonance Spectroscopy ◽  
Blood Storage ◽  
31P Nuclear Magnetic Resonance ◽  
Acid Citrate Dextrose ◽  
Citrate Dextrose ◽  
Citrate Phosphate ◽  
Nuclear Magnetic

Abstract 31P nuclear magnetic resonance (NMR) spectroscopy was used to measure changes in intra-erythrocyte Mg adenosine triphosphate (MgATP) and free Mg2+ during blood storage at 4 degrees C in standard citrate preservation media. The extent of Mg2+ complexation of ATP and the concentration of free Mg2+ were measured from the Mg2+-dependent chemical shift differences, at 22 degrees C, between the P beta and P alpha resonances of intracellular ATP. This difference changed from 721.0 +/- 1.4 Hz (mean +/- SE) on the day of collection to 741.0 +/- 3.4 Hz after three to seven days and 774.0 +/- 2.8 Hz after 11 to 40 days storage in either acid-citrate-dextrose (ACD) or citrate-phosphate- dextrose-adenine (CPDA-1). Changes in intracellular pH, detected from shifts in the intracellular Pi resonance, averaged 0.27 units after 11 to 40 days of storage. These data indicate a sizable decrease in the extent of Mg2+ complexation of ATP, and a decrease by a factor of 2.6 in free Mg2+, during the shelf-life of blood stored in ACD or CPDA-1.

scholarly journals Phosphorus dynamics in sediments of a eutrophic lake derived from 31P nuclear magnetic resonance spectroscopy

2014 ◽  
Vol 65 (1) ◽  
pp. 70 ◽  
Author(s):  
Deniz Özkundakci ◽  
David P. Hamilton ◽  
Richard McDowell ◽  
Stefan Hill
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Water Column ◽  
Bottom Sediments ◽  
Eutrophic Lake ◽  
Resonance Spectroscopy ◽  
31P Nmr Spectroscopy ◽  
31P Nuclear Magnetic Resonance ◽  
Lake Okaro ◽  
Nuclear Magnetic

The determination of organic phosphorus (P) compounds in lake sediments can provide information on the potential for internal P loading. Settling seston and vertical sediment core samples from highly eutrophic Lake Okaro, New Zealand, were collected during a mixed winter and stratified summer period, representing, respectively, when the water column was well oxygenated and when the bottom waters were anoxic. Samples were analysed with 31P nuclear magnetic resonance (31P NMR) spectroscopy, which showed that both bottom sediments and settling seston contained orthophosphate, orthophosphate monoesters and diesters, pyrophosphates, polyphosphates and phosphonates. Phosphorus concentration in settling seston increased ~2.5-fold in winter as a result of seasonally induced changes in phytoplankton biomass, with a marked increase in the concentration of orthophosphate. Several potentially bioavailable P compounds in the bottom sediments were identified that were likely to contribute to recycling of P from the sediment to the water column. An ‘apparent half-life’ was used to quantify the time scales on which these compounds were recycled to the overlying water column. Orthophosphate monoesters that include inositol phosphates were the most persistent P compound. On the basis of half-lives, high internal P loadings may persist for more than 20 years, potentially hindering restoration efforts in Lake Okaro.

Sign in / Sign up

Export Citation Format

Share Document