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Highly Sensitive Magnetic-SERS Dual-Function Silica Nanoprobes for Effective On-Site Organic Chemical Detection.

ABSTRACT: We report magnetic silver nanoshells (M-AgNSs) that have both magnetic and SERS properties for SERS-based detection. The M-AgNSs are composed of hundreds of Fe?O? nanoparticles for rapid accumulation and bumpy silver shell for sensitive SERS detection by near-infrared laser excitation. The intensity of the SERS signal from the M-AgNSs was strong enough to provide single particle-level detection. We obtained much stronger SERS signal intensity from the aggregated M-AgNSs than from the non-aggregated AgNSs. 4-Fluorothiophenol was detected at concentrations as low as 1 nM, which corresponds to 0.16 ppb. The limit of detection for tetramethylthiuram disulfide was 10 ?M, which corresponds to 3 ppm. The M-AgNSs can be used to detect trace amounts of organic molecules using a portable Raman system.

SUBMITTER: Jeong C

PROVIDER: S-EPMC5485793 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Highly Sensitive Magnetic-SERS Dual-Function Silica Nanoprobes for Effective On-Site Organic Chemical Detection.

Jeong Cheolhwan C Kim Hyung-Mo HM Park So Yeon SY Cha Myeong Geun MG Park Sung-Jun SJ Kyeong San S Pham Xuan-Hung XH Hahm Eunil E Ha Yuna Y Jeong Dae Hong DH Jun Bong-Hyun BH Lee Yoon-Sik YS

Nanomaterials (Basel, Switzerland) 20170613 6

We report magnetic silver nanoshells (M-AgNSs) that have both magnetic and SERS properties for SERS-based detection. The M-AgNSs are composed of hundreds of Fe₃O₄ nanoparticles for rapid accumulation and bumpy silver shell for sensitive SERS detection by near-infrared laser excitation. The intensity of the SERS signal from the M-AgNSs was strong enough to provide single particle-level detection. We obtained much stronger SERS signal intensity from the aggregated M-AgNSs than from the non-aggrega ...[more]

PMID: 28608835

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