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Abstract

Although the technology of ion-beam-induced gene transfer into either plant or bacterial cells has been successfully established, relevant mechanisms have not been understood. This work aimed to study the process of induction and thus to develop applications of ion beam bioengineering. Cells of various plant tissues were bombarded in vacuum with argon and nitrogen ion beams at energies of 15-30 keV with fluences ranging from 5 × 10 14 -3 × 10 16 ions/cm 2 . The ion bombardment effects on tissue viability and neutral red dye molecule transfer into the cells through the cell envelope were investigated. The results showed that the characteristics of the tissue survival from the ion bombardment and penetration of the dye molecules into the cells through the cell envelope depended on ion species, energy and fluence. For 30-keV argon-ion bombardment at a fluence of 2 × 10 15 ions/cm 2 , the dye molecules entered the cells without fatal injury, whereas under other conditions, the dye either did not enter the cells or stained the nuclei. On the cell envelope surface, ion-bombardment-induced crater-like structures were observed. Calculations indicated that exogenous molecule transfer into living plant cells can be achieved by ion beams with appropriate physical parameters such that the ion range and the radiation damage range lie within the solid cell wall thickness.

Bioeffects of Low Energy Ion Beam Implantation: DNA Damage, Mutation and Gene Transter

“…Ion bombardment induced certain forms of damage in the cell envelope, such as micro-holes or craters that might play a role in acting as channels for exogenous DNA molecules to be transferred [2] . Similar results were obtained in plant cells [51,65] . VILAITHONGA et al compared the transfer rate of the reported gene into cells with/without ion bombarded, and demonstrated that ions with a suitable energy did elevate gene transfer, as shown in Fig.…”

Ion Beam Bio-Engineering and Crop Breeding

“…Although accurate simulation models and programs are available for metals and semiconductors, theoretic calculation of the sputtering yields of cell walls is much more difficult partly due to the lack of a broad database for complex organic molecules and organisms. The calculated results are corroborated by transmission electron microscopy (TEM) measurements of the cross section of Curcuma embryo cell walls after bombardment by 30 keV Ar + [8] . If the ion flunece and energy are carefully controlled, the ion beam can be used for precise sputtering and thinning of cell walls to expose the inner cellular structures for subsequent analysis [9] .…”

The Role of Reactive Oxygen Species in Plant Response to Radiation

“…In contrast, high doses of ion beam irradiation have been widely shown to inhibit seedling growth, with studies observing dose-dependent growth inhibition in rice seedlings irradiated with carbon ion beams [ 112 ]. Additionally, Vilaithong et al and Apavatjrut et al found that high doses of Ar- or N-ion bombardment retarded the germination and growth of naked corn embryos [ 125 , 126 ]. Similarly, Yang et al observed significant growth inhibition in Arabidopsis primary root elongation, sprouting and survival under a dose of 1.5107 ions cm −2 , while Ya et al observed dose-dependent growth inhibition in rice seedlings under low-energy N + beam injection [ 44 , 113 ].…”