Silver, zinc, and copper nanoparticles were reductively crystallized on thymine-containing single-stranded DNA decanucleotides, in aqueous solutions containing the corresponding metal ions and sodium borohydride, at 4 °C, pH 11.8, and 15 mM of NaCl. Iron nanoparticles were not formed under these conditions. Formation of aggregates was monitored by UV-Vis spectrophotometry, and characterized by scanning electron microscopy and dynamic light scattering. The absorption spectra for most Ag⁺-containing samples showed a major band centered around 425 nm and a shoulder between 500 and 600 nm, indicative of the presence of silver particles in a wide size distribution, in the 0.1–5 μm range. This was verified by micrographs and size distribution observed in scattering profiles. Silver-particle morphology indicates formation of cubic structures instead of spherical geometries. For the case of zinc and copper nanoparticles, quasi-spherical structures of approximately 100 nm were crystallized along the DNA chains by reduction reaction, and then released to the bulk solvent. Thymine residues show a higher effectiveness in nucleation of metallic cations in comparison to other DNA nucleobases, particularly in their deprotonated form, at high pH values. Adenines flanking central runs of deprotonable bases in the model oligonucletide chain affect the production of silver crystals on the DNA decamers. pH value and NaCl concentration have a significant effect on the production of silver particles, as alkaline and moderate-ionic-strength conditions are required to crystallize such structures. The tuning of size and morphology of metallic nanoparticles by the proper choice of oligonucleotide sequence and physical conditions may have interesting applications in the field of nanobiotechnology.

在包含相应金属离子和硼氢化钠的水溶液中，在4°C，pH 11.8和15 mM NaCl的水溶液中，将银，锌和铜纳米颗粒在含胸腺嘧啶的单链DNA十核苷酸上还原性结晶。在这些条件下没有形成铁纳米颗粒。通过UV-Vis分光光度法监测聚集体的形成，并通过扫描电子显微镜和动态光散射进行表征。大多数Ag ⁺的吸收光谱含样品的样品在425 nm附近有一个主要谱带，在500 nm和600 nm之间有一个肩峰，表明存在大小范围在0.1-5μm范围内的银颗粒。通过显微照片和在散射曲线中观察到的尺寸分布对此进行了验证。银粒子形态表明形成立方结构，而不是球形几何形状。对于锌和铜纳米粒子，通过还原反应使DNA链上约100 nm的准球形结构结晶，然后释放到本体溶剂中。与其他DNA核碱基相比，胸腺嘧啶残基在金属阳离子的成核中表现出更高的效率，尤其是在高pH值下以去质子形式存在。在寡核苷酸模型链中，位于可质子化碱基的中央运行旁的腺嘌呤会影响DNA十聚体上银晶体的产生。pH值和NaCl浓度对银颗粒的生产具有重要影响，因为需要碱性和中等离子强度条件才能使这种结构结晶。大小和寡核苷酸序列和物理条件的适当选择的金属纳米颗粒的形态的调谐可以具有在纳米生物技术领域有趣的应用。