Designing and making of plasmonic nanobiosensor with different concentration of mir-21

Mozhgan Barfi,1 Masumeh azizi,2,* Azadeh azizi ,3

1. Shahrekord University of Medical Sciences, Shahrekord, Iran
2. Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
3. Department of Bioscience and Biotechnology, Malek Ashtar University of Technology, Tehran, Iran



Micrornas (mirnas or mirs) are non-coding nucleic sequences which participated in the control of pathological processes and can act as an oncogene or tumor suppressor. for example, mir-21 is an index biomarker that is frequently overexpressed in various human tumors and several cancer cell lines including glioblastoma, head and neck, lung and other cancers. the most common methods for checking alterations in the mirnas expression level are using micro-array chips and real time pcr.however, replacing these methods with simpler and less costly methods is very important for cancer diagnosis and treatment. nowadays, linker mediated self-assembly of gold nanoparticles (gnps) is emerging as an interesting strategy for monitoring the alterations in the mirnas expression level.


Herein, for the first time a plasmonic assembled nano-biosensor has been designed in order to investigate the mir-21 concentration based on enhancement the local surface plasmon resonance (lspr) property of gnps. for this, first gnps were conjugated with thiol-modified rna strands and then have been assembled via mir-21 as a linker. finally hybridization between complementary rna strands was investigated using monitoring the lspr alterations of gnps as a function of mir concentration (0-10 μg/ml).


The results showed that the growth rate of gnps assembly is dependent on the mir-21 concentration and upon the increment of mir concentration; amount of hybridization has been increased


In conclusion, gold nanoparticles self-assembled systems could be used as a new and ultrasensitive sensor for cancer diagnosis researches.


Micrornas, local surface plasmon resonance (lspr), gold nanoparticles (gnps), mir-21