Scholarlink

<p>We characterized a DNA/gold interface designed for the detection of the SARS-CoV-2 RNA-dependent RNA polymerase/Helicase (RdRp/Hel) sequence. Using broadband spectroscopic ellipsometry (SE) and a difference spectra approach, we monitored molecular modifications at the interface, from probe sequence deposition to the insertion of a molecular spacer and subsequent hybridization with the target. The UV region revealed the characteristic DNA absorption peak around 260&#xa0;nm, while changes in δΔ in the NIR correlated with increased optical thickness following each deposition step. The optical response was analyzed as a function of target concentration, and the binding affinity curve, derived from δΔ values at 800&#xa0;nm, was fitted using a first-order Langmuir model, yielding a dissociation constant K<sub>D</sub> = (70 ± 10) nM, consistent with literature values. Selectivity studies demonstrated that the interface effectively discriminates the SARS-CoV-2 sequence from the SARS-CoV HKU variant, even in a crowded environment. A complementary platform targeting the SARS-CoV HKU sequence confirmed selective detection of HKU over SARS-CoV-2. These findings highlight the potential for parallel detection of different viral sequences.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Optical label-free detection of SARS-CoV-2: investigating platform spectroscopic properties for oligonucleotide targeting

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年8月11日

查看全文
  • Silvia Maria Cristina Rotondi,
  • Paolo Canepa,
  • Silvia Dante,
  • Maurizio Canepa,
  • Ornella Cavalleri

摘要

We characterized a DNA/gold interface designed for the detection of the SARS-CoV-2 RNA-dependent RNA polymerase/Helicase (RdRp/Hel) sequence. Using broadband spectroscopic ellipsometry (SE) and a difference spectra approach, we monitored molecular modifications at the interface, from probe sequence deposition to the insertion of a molecular spacer and subsequent hybridization with the target. The UV region revealed the characteristic DNA absorption peak around 260 nm, while changes in δΔ in the NIR correlated with increased optical thickness following each deposition step. The optical response was analyzed as a function of target concentration, and the binding affinity curve, derived from δΔ values at 800 nm, was fitted using a first-order Langmuir model, yielding a dissociation constant KD = (70 ± 10) nM, consistent with literature values. Selectivity studies demonstrated that the interface effectively discriminates the SARS-CoV-2 sequence from the SARS-CoV HKU variant, even in a crowded environment. A complementary platform targeting the SARS-CoV HKU sequence confirmed selective detection of HKU over SARS-CoV-2. These findings highlight the potential for parallel detection of different viral sequences.