کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
10429687 | 909858 | 2005 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Towards a label-free optical porous silicon DNA sensor
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی آنالیزی یا شیمی تجزیه
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چکیده انگلیسی
We report on the fabrication of an optical silicon-based label-free DNA sensor. n-Type crystalline silicon wafers have been electrochemically etched to form porous silicon layers and characterized in terms of porosity, pore distribution, surface composition and photoluminescence. Samples (0.25Â cm2) have been cut and properly derivatized using trimethoxy-3-bromoacetamidopropylsilane in order to link single strand DNA (ss-DNA). Such a molecule is not commercially available and has been ad-hoc prepared by reacting hydrobromic acid and 3-aminopropyltrimethoxysilane in presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide as coupling agent. Trimethoxy-3-bromoacetamidopropylsilane acts as a bridge anchored to the porous silicon surface through the silane group while immobilizing ss-DNA by means of the bromoacetamido moiety. We have found that derivatized samples exhibit a photoluminescence that is stable in time and is not modified after exposure to non-complementary DNA strand. On the other hand, a sensible enhancement of the light emission has been observed when the derivatized samples react with the complementary strand, showing that the specific ss-DNA/complementary DNA (c-DNA) interaction can be optically sensed without using further labeling steps. This strongly strengthens the possible role of silicon as a material for biosensors.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosensors and Bioelectronics - Volume 21, Issue 4, 15 October 2005, Pages 661-665
Journal: Biosensors and Bioelectronics - Volume 21, Issue 4, 15 October 2005, Pages 661-665
نویسندگان
Girolamo Di Francia, Vera La Ferrara, Sonia Manzo, Salvatore Chiavarini,