title: Dynamic-SIMS imaging and quantification of inorganic ions in frozen-hydrated plant samples.
abstract: We present here SIMS images of the distribution of inorganic cations (Na, K, Mg and Ca) in frozen-hydrated samples of three plant species, ivy, camomile, and flax. The samples were cryofixed using fast plunge-freezing. Stigmatic images were obtained, at 100 K, under dynamic SIMS conditions by fast atom bombarding (FAB). Even though the images obtained with the frozen-hydrated plant samples are still not of upper quality, they show that the method used to prepare these samples preserves existing ionic gradients between the outer and the inner part of the cells, between adjacent cells, including cells with the same type of differentiation, and between tissues. We also describe the quantification of the relative proportions of the ions in the vacuoles of flax. The reasonable accuracy achieved for quantification of the vacuole ion ratios permitted to show (i) that radial gradients of ion ratios in hypocotyls change when the plant is becoming older and (ii) that large differences may exist between adjacent cortical cells of the same type. The role of these substantial differences in vacuole ion balance ratios is a largely unexplored issue in plant physiology.
authors.affiliation: Laboratoire Assemblages moléculaires: modélisation et imagerie SIMS, FRE CNRS 2829, Faculté des Sciences de l'Université de Rouen, 76821 Mont Saint Aignan Cedex, France.
authors.forename: Cedric
authors.initials: C
authors.lastname: Dérue
authors.forename: David
authors.initials: D
authors.lastname: Gibouin
authors.forename: Maurice
authors.initials: M
authors.lastname: Demarty
authors.forename: Marie-Claire
authors.initials: MC
authors.lastname: Verdus
authors.forename: Fabrice
authors.initials: F
authors.lastname: Lefebvre
authors.forename: Michel
authors.initials: M
authors.lastname: Thellier
authors.forename: Camille
authors.initials: C
authors.lastname: Ripoll
mesh_terms: D002412:Cations / Q000032:analysis*; D020843:Chamomile / Q000737:chemistry; D002623:Chemistry Techniques, Analytical / Q000379:methods*; D015925:Cryopreservation; D019597:Flax / Q000737:chemistry; D005615:Freezing; D008670:Metals / Q000032:analysis*; D010784:Photomicrography; D010944:Plants / Q000737:chemistry*; D018629:Spectrometry, Mass, Secondary Ion; D012251:Toxicodendron / Q000737:chemistry; D014617:Vacuoles / Q000737:chemistry
chemical_list: D002412:Cations; D008670:Metals