Preparation of Fe₃O₄-Embedded Poly(styrene)/Poly(thiophene) Core/Shell Nanoparticles and Their Hydrogel Patterns for Sensor Applications

Yong Seok Kim; Hyun Jong Lee; Patakamuri Govindaiah; Woohyun Son; Won-Gun Koh; In Woo Cheong; Jung Hyun Kim

doi:10.3390/ma7010195

Preparation of Fe₃O₄-Embedded Poly(styrene)/Poly(thiophene) Core/Shell Nanoparticles and Their Hydrogel Patterns for Sensor Applications

Materials (Basel). 2014 Jan 2;7(1):195-205. doi: 10.3390/ma7010195.

Authors

Yong Seok Kim¹, Hyun Jong Lee², Patakamuri Govindaiah³, Woohyun Son⁴, Won-Gun Koh⁵, In Woo Cheong⁶, Jung Hyun Kim⁷

Affiliations

¹ Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemoon-Gu, Seoul 120-749, Korea. genie0719@daum.net.
² Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemoon-Gu, Seoul 120-749, Korea. bml@yonsei.ac.kr.
³ Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemoon-Gu, Seoul 120-749, Korea. govindaiah@gmail.com.
⁴ Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemoon-Gu, Seoul 120-749, Korea. roxxn.son@gmail.com.
⁵ Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemoon-Gu, Seoul 120-749, Korea. wongun@yonsei.ac.kr.
⁶ Department of Applied Chemistry, Kyungpook National University, 80 Daehakro, Bukgu, Daegu 702-701, Korea. inwoo@knu.ac.kr.
⁷ Department of Chemical and Biomolecular Engineering, Yonsei University, 50 Yonsei-ro, Seodaemoon-Gu, Seoul 120-749, Korea. jayhkim@yonsei.ac.kr.

Abstract

This research describes the preparation and sensor applications of multifunctional monodisperse, Fe₃O₄ nanoparticles-embedded poly(styrene)/poly(thiophene) (Fe₃O₄-PSt/PTh), core/shell nanoparticles. Monodisperse Fe₃O₄-PSt/PTh nanoparticles were prepared by free-radical combination (mini-emulsion/emulsion) polymerization for Fe₃O₄-PSt core and oxidative seeded emulsion polymerization for PTh shell in the presence of FeCl₃/H₂O₂ as a redox catalyst, respectively. For applicability of Fe₃O₄-PSt/PTh as sensors, Fe₃O₄-PSt/PTh-immobilized poly(ethylene glycol) (PEG)-based hydrogels were fabricated by photolithography. The hydrogel patterns showed a good sensing performance under different H₂O₂ concentrations. They also showed a quenching sensitivity of 1 µg/mL for the Pd²⁺ metal ion within 1 min. The hydrogel micropatterns not only provide a fast water uptake property but also suggest the feasibility of both H₂O₂ and Pd²⁺ detection.

Keywords: fluorescence; hydrogel patterns; nanoparticles; polythiophene; sensor.