Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS Detection
A sharpened control over the parameters affecting the synthesis of plasmonic nanostructures is often crucial for their application in biosensing, which, if based on surface-enhanced Raman spectroscopy (SERS), requires well-defined optical properties of the substrate. In this work, a method for the m...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-12-01
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| Series: | Biosensors |
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| Online Access: | https://www.mdpi.com/2079-6374/11/12/520 |
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| author | Niccolò Paccotti Alessandro Chiadò Chiara Novara Paola Rivolo Daniel Montesi Francesco Geobaldo Fabrizio Giorgis |
| author_facet | Niccolò Paccotti Alessandro Chiadò Chiara Novara Paola Rivolo Daniel Montesi Francesco Geobaldo Fabrizio Giorgis |
| author_sort | Niccolò Paccotti |
| collection | DOAJ |
| description | A sharpened control over the parameters affecting the synthesis of plasmonic nanostructures is often crucial for their application in biosensing, which, if based on surface-enhanced Raman spectroscopy (SERS), requires well-defined optical properties of the substrate. In this work, a method for the microfluidic synthesis of Ag nanoparticles (NPs) on porous silicon (pSi) was developed, focusing on achieving a fine control over the morphological characteristics and spatial distribution of the produced nanostructures to be used as SERS substrates. To this end, a pSi membrane was integrated in a microfluidic chamber in which the silver precursor solution was injected, allowing for the real-time monitoring of the reaction by UV–Vis spectroscopy. The synthesis parameters, such as the concentration of the silver precursor, the temperature, and the flow rate, were varied in order to study their effects on the final silver NPs’ morphology. Variations in the flow rate affected the size distribution of the NPs, whereas both the temperature and the concentration of the silver precursor strongly influenced the rate of the reaction and the particle size. Consistently with the described trends, SERS tests using 4-MBA as a probe showed how the flow rate variation affected the SERS enhancement uniformity, and how the production of larger NPs, as a result of an increase in temperature or of the concentration of the Ag precursor, led to an increased SERS efficiency. |
| first_indexed | 2024-03-09T04:35:29Z |
| format | Article |
| id | doaj.art-049c758eb1d844e89b21a38d1ed8c643 |
| institution | Directory Open Access Journal |
| issn | 2079-6374 |
| language | English |
| last_indexed | 2024-03-09T04:35:29Z |
| publishDate | 2021-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Biosensors |
| spelling | doaj.art-049c758eb1d844e89b21a38d1ed8c6432023-12-03T13:28:23ZengMDPI AGBiosensors2079-63742021-12-01111252010.3390/bios11120520Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS DetectionNiccolò Paccotti0Alessandro Chiadò1Chiara Novara2Paola Rivolo3Daniel Montesi4Francesco Geobaldo5Fabrizio Giorgis6Department of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, ItalyDepartment of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, ItalyDepartment of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, ItalyDepartment of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, ItalyDepartment of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, ItalyDepartment of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, ItalyDepartment of Applied Science and Technology, Politecnico di Torino, C.so Duca degli Abruzzi 24, 10129 Torino, ItalyA sharpened control over the parameters affecting the synthesis of plasmonic nanostructures is often crucial for their application in biosensing, which, if based on surface-enhanced Raman spectroscopy (SERS), requires well-defined optical properties of the substrate. In this work, a method for the microfluidic synthesis of Ag nanoparticles (NPs) on porous silicon (pSi) was developed, focusing on achieving a fine control over the morphological characteristics and spatial distribution of the produced nanostructures to be used as SERS substrates. To this end, a pSi membrane was integrated in a microfluidic chamber in which the silver precursor solution was injected, allowing for the real-time monitoring of the reaction by UV–Vis spectroscopy. The synthesis parameters, such as the concentration of the silver precursor, the temperature, and the flow rate, were varied in order to study their effects on the final silver NPs’ morphology. Variations in the flow rate affected the size distribution of the NPs, whereas both the temperature and the concentration of the silver precursor strongly influenced the rate of the reaction and the particle size. Consistently with the described trends, SERS tests using 4-MBA as a probe showed how the flow rate variation affected the SERS enhancement uniformity, and how the production of larger NPs, as a result of an increase in temperature or of the concentration of the Ag precursor, led to an increased SERS efficiency.https://www.mdpi.com/2079-6374/11/12/520microfluidic synthesisin situ monitoringAg nanostructuresporous siliconSERS |
| spellingShingle | Niccolò Paccotti Alessandro Chiadò Chiara Novara Paola Rivolo Daniel Montesi Francesco Geobaldo Fabrizio Giorgis Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS Detection Biosensors microfluidic synthesis in situ monitoring Ag nanostructures porous silicon SERS |
| title | Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS Detection |
| title_full | Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS Detection |
| title_fullStr | Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS Detection |
| title_full_unstemmed | Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS Detection |
| title_short | Real-Time Monitoring of the In Situ Microfluidic Synthesis of Ag Nanoparticles on Solid Substrate for Reliable SERS Detection |
| title_sort | real time monitoring of the in situ microfluidic synthesis of ag nanoparticles on solid substrate for reliable sers detection |
| topic | microfluidic synthesis in situ monitoring Ag nanostructures porous silicon SERS |
| url | https://www.mdpi.com/2079-6374/11/12/520 |
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