Energy Dispersive Quantitative X-ray Microanalysis For Plant Materials

The purpose of the paper is to research how to apply EMAX-EDS to the study of plant science.We investigated the application of EMAX-EDS in some domains,such as methods of electron microscopy cytochemical and energy dispersive X-ray analysis techniques;standardless X-ray quantitative microanalysis;internal-carbon standards X-ray quantitative microanalysis;and recommend how to mainten EMAX-EDS routinely,and common problems are how to be solved.The main results are summarized as follows:1.the application of EMAX-EDS in electron microscopy cytochemistry.The study,Changes of Ca²⁺ distribution in blade cells of Populus simonii×Populus pyramidalis'Opera 8277' treated by inhibitor eosin B and/or mechanical damage were determined by cytochemical methods with X-ray microanalysis,show that the distribution of Ca²⁺changed obviously treated by inhibitor eosin B and/or mechanical damage.Ca²⁺ deposited in cytoplasm,nucleus,cytoderm, chloroplast outer membrane,this is be consistent with physiological action of C²⁺ in cells2.standardless quantitative X-ray microanalysisstandardless quantitative X-ray microanalysis for three plant samples showed that,Rhizophora apiculata is a halophyte;after Kosteletzkya virginica was treated with 400mM NaCl,Cl^-,Na⁺,K⁺ mainly distributed in epidermis,inside ofmesosphere and ectocondyle of central cylinder;.3.quantitative X-ray microanalysis for internal-carbon standardsIn this study,we used the signal of endogenous carbon as an internal standard,providing a similar (X-ray absorbing) background carbon for other elements to be quantified.The final formula for quantification of an element was obtained as:(CTS/CTS_C)^* 100.A linear regrssion,(CTS/CTS_C)^* 100 against standard concentration,was constructed.The effects of instrumental conditions and background on element-specific peak counts were cancelled out by similar effects on carbon..Thus,analytical datum from the linear regression are reliable,analytical data of thick samples is more accurate,but error rate is higher;accuracy of analytical data of semi-thin sample is lower;but error rate is lower too.4.Daily maintenance and repair,common problems and recommended solutions for EMAX-EDSTo guarantee increase of service life of EDS,it is advisable to take the following measures:The instrument must be properly operated when we investigate materials with it,and it's Si(Li) detector must be protected;supplement of liquid nitrogen into the Dewar;conditionning regularly;the primary determinant of true analytical data are reasonable parameters and normal running...