Guanhong Liu,Peipei Ren,Fan Yang,Xuekai Dou,Jun Wang,Youtao Song
Two novel isomeric colorimetric probes are established for simultaneous determination of copper ions using 2-hydroxy-5-methoxybenzaldehyde fluorescein hydrazone (5-HMBA-FH) and 2-hydroxy-3-methoxybenzaldehyde fluorescein hydrazone (3-HMBA-FH). They are synthesized by reacting fluorescein hydrazide with 2-hydroxy-5-methoxybenzaldehyde and 2-hydroxy-3-methoxybenzaldehyde, respectively, and then characterized by 1H-NMR, 13C-NMR, and infrared spectrum. The addition of copper ions to the solutions of two novel colorimetric probes can generate the obviously peaks at 498 nm in UV–vis absorption spectra along with a rapid colour change from colourless to dark yellow. The detection limits of the method for Cu2+ ion were 3.442 × 10−6 mol/L and 3.682 × 10−6 mol/L separately for 5-HMBA-FH and 3-HMBA-FH, respectively. The additions of other metal ions hardly affect the determination of copper ions. The proposed method was successfully applied to the analysis of Cu2+ ions in various samples. This method possesses high sensitivity, high simplicity, and minimized interference and will provide a great advantage in detecting copper ions in the environment, food, and medical applications.
Marine biofouling which interferes with normal marine operation and also causes huge economic loss has become a worldwide problem. With the development of society, there is an urgent need to develop non-toxic and efficient anti-fouling strategies. Capsaicin is an environmentally friendly antifouling agent, but controlling the stable release of capsaicin from the coating is still a challenge to be solved. To achieve long-lasting antifouling property, in this work, we incorporate a derivative of capsaicin N-(4-hydroxy-3-methoxybenzyl)acrylamide (HMBA) to prepare double network (DN) hydrogels and make HMBA a part of the polymer network. Polyvinyl alcohol (PVA) has good hydrophilicity, and as a soft and ductile network, acrylamide (AM) and HMBA can polymerize to generate a rigid and brittle network. By adjusting the content of HMBA in the DN hydrogels, we can obtain a PVA–PAHX hydrogel with high mechanical strength, low swelling rate, and excellent antifouling effect, which provides a feasible way for the practical application of a hydrogel coating in long-term marine antifouling.
危险品化学品经营许可证（带存储）