Skip Navigation Links
Journal of Environmental Accounting and Management
António Mendes Lopes (editor), Jiazhong Zhang(editor)
António Mendes Lopes (editor)

University of Porto, Portugal


Jiazhong Zhang (editor)

School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi Province 710049, China

Fax: +86 29 82668723 Email:

Optimization of the Gram Staining Method Based on Superparamagnetic Magnetic Nanobeads

Journal of Environmental Accounting and Management 6(3) (2018) 263--271 | DOI:10.5890/JEAM.2018.09.007

Yuren Feng; Zihe Ren; Fuhua Wu; Annika Reichert; Yun Lu

School of Environment, Tsinghua University, Beijing, 100084, China

Download Full Text PDF



Gram staining is a widely used method for bacterial identification, where an alcohol burner is used as the fixed step, which requires a high level of proficiency, while the open flame is a potential fire hazard. A rapid, convenient and alternative method is also vailable that does not require a microscope or alcohol burner. This method utilizes the adsorption capacity of magnetic nanobeads. Ferriferous oxide beads are made by means of the co-precipitation method and adsorb bacteria in suspension liquid after being coated on the surface. The staining process omits the “heat” step and the need for a microscope, and distinguishes bacteria through the observation of the color of the liquid. According to our results, the behavior of this magnetic material performs well with various types of microbes. In particular, the color is clear and is easily distinguishable.


This work was supported by the National Key R&D Program of China (2016YFC0401405) and the National Key R&D Program of China for International Science & Innovation Cooperation Major Project between Governments (2016YFE0118800).


  1. [1]  Akikazu, S.D. and Takashi, O.D. (2012), Virus capture using anionic polymer-coated magnetic beads (Review), International Journal of Molecular Medicine, 30, 37.
  2. [2]  Ikner, L.A., Soto-Beltran, M., and Bright, K.R. (2011), New method using a positively charged microporous filter and ultrafiltration for concentration of viruses from tap water, Applied and Environmental Microbiology, 77(10), 35003506.
  3. [3]  Li, Q.Q., Chen, P., and Ren, C.F. (2012), Comparative study on the adsorption performance of different magnetic beads, Health Research, 41(2), 293297.
  4. [4]  Lu, Z.Y.,Wang, G., Zhuang, J.Q., and Yang,W.S. (2006), Effects of the concentration of tetramethylammonium hydroxide peptizer on the synthesis of Fe3O4/SiO2 core/shell nanoparticles, Colloids and Surfaces, 278, 140143.
  5. [5]  Meng, L. (2012), Preparation, characterization and application of Fe3O4 nano-magnetic particles, Hunan: Central South University (in Chinese).
  6. [6]  Qiu, J., Fan, X.J., and Sheng, S. (2006), Study on the adsorption performance of self-made nude magnetic beads on common foodborne pathogenic bacteria, Modern Preventive Medicine, 33(1), 45.
  7. [7]  Sizemore, R.K., Caldwell, J.J., and Kendrick, A.S. (1990), Alternate gram staining technique using a fluorescent lectin, Applied and Environmental Microbiology, 56(7), 22452247.
  8. [8]  Wang, X. (2004), The optimization of Fe3O4/SiO2 composite nano magnetic bead preparation technology and its application in DNA isolation and purification, Beijing: Beijing University of Chemical Technology (in Chinese).
  9. [9]  Yazdankhah, S.P., Sørum, H., Larsen, H.J.S., and Gogstad, G. (2001), Use of magnetic beads for Gram staining of bacteria in aqueous suspension, Journal of Microbiological Methods, 47, 369371.