Surface modified gold nanoparticles can be applied in various fields with increased chemical resistance. In this study, gold nanoparticles were treated with sugar molecules to improve chemical stability. Glucose known as a reducing sugar, sucrose or trehalose, which is non-reducing sugars, was added to a dispersion of gold nanoparticles synthesized with citrate as a reducing agent. The color and absorbance of the dispersion were evaluated for colloidal stability. As a result, there was no significant difference in the size, shape, and optical properties of gold nanoparticles depending on the type of sugar. After the addition of PBS, dispersion stability was evaluated and the aggregation reaction over time was analyzed. It was found, the gold nanoparticles coated with the non-reducing sugar were more stable than those with the reducing sugar. Higher molecular weight sugar prevented the particle agglomeration. Therefore, it is expected that gold nanoparticles coated with non-reducing sugar can be applied stably in high ionic condition.

금 나노입자는 표면개질을 통해 내화학성을 높여 활용분야를 넓힐 수 있다. 본 연구는 당을 이용하여 화학적 환원법으로 제조된 금 나노입자의 표면 안정성을 개선하고자 하였다. 환원제로 Citrate를 사용하여 합성한 금 나노입자 분산액에 환원당인 glucose, 비환원당인 sucrose와 trehalose를 첨가한 후, 분산액의 색상 및 흡광도로 콜로이드 안정성을 평가하였다. 그 결과 금 나노입자의 크기와 형태 및 광학적 특성은 당의 종류 및 코팅 유무에 따른 유의한 차이는 보이지 않았다. PBS를 첨가한 후 분산 안정성을 평가하고, 시간에 따른 응집반응을 분석한 결과 환원당에 비해 비환원당으로 코팅된 금 나노입자가 더 안정적이었으며, 분자량이 높을수록 응집 저항성이 높게 나타났다. 따라서 비환원당으로 코팅된 금 나노입자는 이온농도가 높은 환경에서 금 나노입자를 안정적으로 적용할 수 있을 것으로 기대한다.

Keywords: gold nanoparticle, colloidal stability, sugar molecules, surface modification, aggregation reaction.