Study On Application Of Microdialysis Sampling From Living Plant

In this paper, microdialysis technology was introduced to sample from plant in vivo and the application of microdialysis technology in sampling from plant in vivo was investigated. The study results were showed as follows:Firstly, the varieties of invitro recovery of microdialysis probe were discussed before and after microdialysis sampling from plant in vivo. Taking pot cultured Populus-wutunenses as sample object and plant hormones as testing factors, the plant hormones were determined by HPLC. The invitro recovery of microdialysis probe were determined before and after microdialysis sampling each time. The results showed that microdialysis technology in sampling of plant in vivo was feasible; the initial invitro recovery of microdialysis probe was relatively lower, while the successive recovery was gradually increased to the maximum level, then decreased by degrees; the microdialysis probe could be repeatedly used to sample from plant in vivo and the invitro recoveries of microdialysis probe were different each time. Therefore it is necessary to determine the invitro recovery of microdialysis probe each time in order to modify the measurement value of testing materials in sample before the quantitative determination.Secondly, the affecting factors of the vitro recovery of probes were studied during microdialysis sampling. The results showed that vitro recovery of probe was high when the perfusion rate was low; when perfusion rate was fixed, the varieties of hormone concentration outside probe were little influenced or almost were negligible; even the same type probes, there were also significant differences in vitro recovery among different probes. Therefore we couldn't use the vitro recovery of one probe to speculate another one; within certain sampling time, the vitro recovery of probe had no obvious change and the probe had excellent stability; the change of temperature had great influence on the vitro recovery of probe; the higher temperature was, the higher vitro recovery of probe was.Thirdly, Taking Populus-wutunenses and Schefflera octophylla as experimental materials and adopting the method of MD-HPLC, the sample of endogenous hormone was obtained and determined. The dialysate was collected during different period after microdialysis probe was inserted into living tender stem. Chromatographic conditions of HPLC were: inertsil ODS-SP column with the temperature of 30℃; the mobile phase consisted of methanol and ultrapure water with phosphoric acid (0.2%)(60:40(v/v)); flow rate 0.6mL/min; detection wavelength was 203nm(GA), 273nm(CTK); 214nm(IAA), 263nm(ABA). The sample of dialysate was directly injected under the certain chromatographic conditions to separate and determine gibberellin(GA), cytokinin(CTK), indoleacetic acid(IAA), abscisic acid (ABA) in tender stem and apoplast. Preliminary study was conducted to test the changes of endogenous hormone of Populus-wutunenses under salt stress. The results showed that ABA content in Populus-wutunenses was obviously increased. The method made the recoveries of samples more than 90%, the RT of RSD among 0.013%～0.105%., and the value of linear correlations (r) were above 0.999. This method realized determination of plant endogenous hormone in vivo, real-time and on-line.