Huang Jin, Gotoh Takehiko, Nakai Satoshi, Ueda Akihiro
Graduate School of Advanced Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Hiroshima, Japan.
Graduate School of Integrated Sciences for Life, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Hiroshima, Japan.
Gels. 2024 May 20;10(5):348. doi: 10.3390/gels10050348.
Over the years, the concentration of cadmium in soil has increased due to industrialization. Cadmium in the soil enters the human body through plant accumulation, seriously endangering human health. In the current study, two types of hydrogels were successfully synthesized using a free radical polymerization method: an ion-type hydrogel referred to as DMAPAA (-(3-(Dimethyl amino) propyl) acrylamide)/DMAPAAQ (,-Dimethyl amino propyl acrylamide, methyl chloride quaternary) and a non-ion-type hydrogel known as DMAA (,-Dimethylacrylamide). In the experiment carried out in this study, the ion-type hydrogel DMAPAA/DMAPAAQ was introduced to cadmium-contaminated soil for vegetable cultivation. The study found that at cadmium levels of 0 and 2 mg/kg in soil, when exposed to a pH 2 solution, cadmium wasn't detected in the filtrate using ICP. As the amount of cadmium increased to 500 mg/kg, hydrogel addition gradually reduced the filtrate cadmium concentration. Notably, the use of the 4% hydrogel resulted in 0 mg/L of cadmium. For the 0% hydrogel, vegetable cadmium absorption was determined to be 0.07 mg/g, contrasting with 0.03 mg/g for the 4% hydrogel. The DMAPAA/DMAPAAQ hydrogel significantly boosts vegetable growth by efficiently absorbing nitrate ions through ion exchange, releasing them for plant uptake. In contrast, the DMAA hydrogel, used as a control, does not enhance plant growth despite its water absorption properties. In summary, the composite hydrogel shows great potential for enhancing vegetable yield and immobilizing heavy metals in soil.
多年来，由于工业化，土壤中镉的浓度有所增加。土壤中的镉通过植物积累进入人体，严重危害人类健康。在当前的研究中，采用自由基聚合法成功合成了两种类型的水凝胶：一种离子型水凝胶称为DMAPAA（-(3-(二甲基氨基)丙基)丙烯酰胺）/DMAPAAQ（,-二甲基氨基丙基丙烯酰胺，甲基氯季铵盐），另一种非离子型水凝胶称为DMAA（,-二甲基丙烯酰胺）。在本研究进行的实验中，将离子型水凝胶DMAPAA/DMAPAAQ引入镉污染土壤中进行蔬菜种植。研究发现，在土壤镉含量为0和2 mg/kg时，当暴露于pH 2的溶液中，使用电感耦合等离子体质谱（ICP）在滤液中未检测到镉。随着镉含量增加到500 mg/kg，添加水凝胶逐渐降低了滤液中镉的浓度。值得注意的是，使用4%的水凝胶时镉浓度为0 mg/L。对于0%水凝胶，测定蔬菜镉吸收量为0.07 mg/g，而4%水凝胶为0.03 mg/g。DMAPAA/DMAPAAQ水凝胶通过离子交换有效吸收硝酸根离子，释放出来供植物吸收，从而显著促进蔬菜生长。相比之下，作为对照的DMAA水凝胶尽管具有吸水性能，但并未促进植物生长。总之，复合水凝胶在提高蔬菜产量和固定土壤中的重金属方面显示出巨大潜力。
