Ultrasensitive fluorescence immunosensor based on mesoporous silica and magnetic nanoparticles: Capture and release strategy

Zhaleh Ghafary; Rahman Hallaj; Abdollah Salimi; Sudabeh Mafakheri

doi:10.1016/j.saa.2021.119749

Ultrasensitive fluorescence immunosensor based on mesoporous silica and magnetic nanoparticles: Capture and release strategy

Spectrochim Acta A Mol Biomol Spectrosc. 2021 Aug 5:257:119749. doi: 10.1016/j.saa.2021.119749. Epub 2021 Mar 26.

Authors

Zhaleh Ghafary¹, Rahman Hallaj², Abdollah Salimi³, Sudabeh Mafakheri⁴

Affiliations

¹ Department of Chemistry, University of Kurdistan, P.O. Box 416, Sanandaj, Iran.
² Department of Chemistry, University of Kurdistan, P.O. Box 416, Sanandaj, Iran; Nanotechnology Research Center, University of Kurdistan, P.O. Box 416, Sanandaj, Iran. Electronic address: Rhallaj@uok.ac.ir.
³ Department of Chemistry, University of Kurdistan, P.O. Box 416, Sanandaj, Iran; Nanotechnology Research Center, University of Kurdistan, P.O. Box 416, Sanandaj, Iran.
⁴ Department of Agriculture and Natural Resources, Imam Khomeini International University, Qazvin, Iran.

PMID: 33862371
DOI: 10.1016/j.saa.2021.119749

Abstract

Herein we designed a novel, highly sensitive, simple and amplified fluorescence immunosensing strategy for hepatitis B virus surface antigen (HBV surface antigen) (HBsAg) as a model based on the construction of a sandwich type probe. The operation mechanism of this immunosensing strategy is implemented by capturing and then stimulation-based-releasing of entrapped dye in the fluorescent capsules. The proposed probe is made by the Fe₃O₄ magnetic nanoparticle (Fe₃O₄ MNP) as a probe collector site and the Rhodamine B loaded-mesoporous silica nanoparticle (MSN-Rh.B) as a fluorescent mesoporous capsule and signal amplifier site. Such a methodology is benefited, from the advantages of the high ability of MSNs to be used as a scaffold for efficient dye encapsulation and the magnetic nanoparticles as efficient biological carriers. Under optimal conditions, the fluorescence signal (The fluorescence of solutions was measured using a quartz fluorescence cell (PMT voltage:720, Ex wavelegth:540, Em wavelength:568, All measurements were carried out at room temperature) increased with the increment of HBsAg concentration in the linear dynamic range of 6.1 ag/ml to 0.012 ng/ml with a detection limit (LOD) of 5.7 ag/ml. The relative standard deviation, measured between the resulting fluorescence peaks was obtained by 6.0%.

Keywords: Fluorescence sensor; Hepatitis B; Immunosensor; MSN; Magnetosensor; Rhodamine B.

MeSH terms

Biosensing Techniques*
Hepatitis B Surface Antigens
Immunoassay
Magnetite Nanoparticles*
Nanoparticles*
Silicon Dioxide

Substances

Hepatitis B Surface Antigens
Magnetite Nanoparticles
Silicon Dioxide