Submit Manuscript  

Article Details

Sensitivity Enhancement in the Colorimetric/Spectroscopic Determination of Lysozyme Concentration in Nanomolar Level with Colloidal Citrat e Capped Au@Ag Core-shell Nanoparticles

[ Vol. 11 , Issue. 4 ]


Debasish Aich, Rudra N. Mondal, Satyajit Saha, Pijus K. Samanta, Amit K. Bhunia and Tapanendu Kamilya*   Pages 5 - 18 ( 14 )


Background: Lysozyme level in body fluids is a significant indicator of various diseases. Cheap and simple colorimetric detection of lysozyme, in biological sample, by gold and silver nanoparticles is a field of interest of nanoparticle research for more than a decade.

Objective: We report here an attempt to improve the sensitivity part of the colorimetric lysozyme detection process by using citrate capped gold-silver core-shell nanoparticles without any functionalization.

Methods: Performance of gold-silver core-shell nanoparticles in determining of lysozyme concentration in water is done using colorimetric/spectroscopic technique. Gold nanoparticles, silver nanoparticles and mixed colloidal suspension of gold and silver nanoparticles, for comparison have also been studied. Selectivity study has been performed through spectroscopic analysis, red-greenblue colour component analysis and fractal dimension analysis of the nanoparticles interacted with several low and high isoelectric point proteins.

Results: Gold-silver core-shell nanoparticles showed higher sensitivity for a wider range of lysozyme concentration compared to gold and silver nanoparticles prepared by us or reported in literature. Gold nanoparticles showed higher sensitivity compared to the core-shell nanoparticles, but for a narrow concentration range of lysozyme. For silver nanoparticles and the mixed nanoparticle system, both sensitivity and range of determination of lysozyme concentration were much smaller compared to the core-shell nanoparticles. Core-shell nanoparticles showed better selectivity compared to gold nanoparticles in identifying aquatic solution of lysozyme from that of other proteins.

Conclusion: Gold-silver core-shell nanoparticles have higher sensitivity in determining wide range of lysozyme concentration in water compared to gold and silver nanoparticles reported in literature.


Lysozyme, core-shell nanoparticles, spectroscopic, plasmon coupling, colorimetric, sensitivity.


Department of Physics, Kharagpur College, West Bengal, Kharagpur, Department of Physics, Kharagpur College, West Bengal, Kharagpur, Department of Physics and Technophysics, Vidyasagar University, West Bengal, Midnapore, Department of Physics, Prabhat Kumar College, West Bengal, Contai, Department of Physics, Government General Degree College, Gopiballavpur-II, West Bengal, Belaberya, Department of Physics, Narajole Raj College, West Bengal, Narajole

Read Full-Text article