Microchimica Acta

, 186:162 | Cite as

Raman spectroscopic imaging of pH values in cancerous tissue by using polyaniline@gold nanoparticles

  • Zicheng Li
  • Ling Xia
  • Gongke LiEmail author
  • Yuling HuEmail author
Original Paper


A core-shell nanocomposite consisting of polyaniline and gold nanoparticles (PANI@AuNPs) is shown to enable intracellular monitoring of pH values by surface-enhanced Raman scattering (SERS) spectroscopy. The method exploits the pH-responsive property of PANI and the SERS-enhancing effect of AuNPs. The intensity of the PANI Raman peak at 1164 cm−1 decreases on increasing the pH value from 4.6 to 7.4. This is the pH range encountered in normal cells and in cancer cells. The PANI@AuNPs were incorporated into HeLa cancer cells and 5 other kinds of cells for Raman based imaging of pH values. The results show that this pH nanoprobe can be applied for imaging of both normal cells and cancer cells. The core-shell composite was also applied to tissue imaging. In our perception, this core-shell nanoprobe is a valuable tool for imaging pH values of cancerous tissue.

Graphical abstract

Schematic presentation of a core-shell nanocomposite, polyaniline@gold nanoparticle, which was synthesized via a rapid method. With the pH of solution changing from alkaline to acidic, the polyaniline can change from emeraldine base (EB, blue shell) transition to emeraldine salt (ES, green shell) transition. Due to the pH-responsive property of polyaniline combined with the surface-enhanced Raman scattering spectroscopy effect of AuNPs. The polyaniline@gold nanoparticles were successfully applied as an intracellular pH probe.


Stimuli-responsive polymer Intracellular sensing Surface-enhanced Raman scattering pH-pribe Cell imaging Tissue imaging 



The work was supported by the National Natural Science Foundation of China (Nos.21675178, 21575168 and 21575167), the Guangdong Provincial Natural Science Foundation of China (No. 2017A030313070), and the Special Funds for Public Welfare Research and Capacity Building in Guangdong Province of China (No. 2015A030401036), the National Key Research and Development Program of China (Nos. 2018YFC1603201), and the Guangzhou Science and Technology Program of China (Nos. 201604020165 and 201704020040), respectively.

Compliance with ethical standards

The author(s) declare that they have no competing interests.


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Copyright information

© Springer-Verlag GmbH Austria, part of Springer Nature 2019

Authors and Affiliations

  1. 1.School of ChemistrySun Yat-sen UniversityGuangzhouChina

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