Péter Tamás, Takács Dóra, Viczián Dániel, Katana Bojana, Alsharif Nizar B, Szilagyi István
MTA-SZTE Lendület Biocolloids Research Group, Department of Physical Chemistry and Materials Science, Interdisciplinary Excellence Centre, University of Szeged, Szeged H-6720, Hungary.
Institute of Condensed Matter and Nanosciences - Bio and Soft Matter, Université catholique de Louvain, Louvain-la-Neuve B-1348, Belgium.
J Phys Chem B. 2025 Jul 10;129(27):6879-6885. doi: 10.1021/acs.jpcb.5c01256. Epub 2025 Jun 25.
Prussian blue (PB) nanozymes have emerged as durable enzyme-mimicking catalysts with broad applications across many fields. Practical uses often involve exposure to salinity that influences their colloidal and catalytic behaviors, yet the specific effects of ions on PB particles are underexplored. This study investigates how electrolyte type and concentration affect the colloidal stability and enzyme-like activity of PB nanozymes using monovalent (NaCl, KCl, CsCl) and multivalent ions (CaCl, LaCl). Electrophoresis and dynamic light scattering measurements revealed that both concentration and ion composition significantly affect stability with specific ion adsorption altering charge density and aggregation, consistent with the DLVO theory. Findings further indicate that higher ionic strengths compress the electric double layer, improving substrate accessibility and accelerating horseradish peroxidase (HRP)-like catalytic reactions. Remarkably, Cs ions substantially boost activity through their unique ability to disrupt water structure and integrate into PB's lattice. These findings highlight the importance of considering ion specificity when designing PB-containing dispersions for optimal stability and catalytic performance.
普鲁士蓝（PB）纳米酶已成为一种耐用的类酶催化剂，在许多领域有着广泛应用。实际应用中常常会接触到盐度，这会影响其胶体和催化行为，但离子对PB颗粒的具体影响尚未得到充分研究。本研究使用单价离子（NaCl、KCl、CsCl）和多价离子（CaCl、LaCl），研究了电解质类型和浓度如何影响PB纳米酶的胶体稳定性和类酶活性。电泳和动态光散射测量结果表明，浓度和离子组成都会显著影响稳定性，特定离子的吸附会改变电荷密度和聚集情况，这与DLVO理论一致。研究结果进一步表明，较高的离子强度会压缩双电层，提高底物可及性并加速类似辣根过氧化物酶（HRP）的催化反应。值得注意的是，Cs离子通过其独特的破坏水结构并融入PB晶格的能力，大幅提高了活性。这些发现凸显了在设计含PB的分散体以实现最佳稳定性和催化性能时，考虑离子特异性的重要性。
