HYBRID EVENT: You can participate in person at Orlando, USA or Virtually from your home or work.

6th edition of World Nanotechnology Conference

April 24-25, 2023

April 24 -26, 2023 | Orlando, USA
World Nano 2022

Modified synthesis of dextrin-capped gold nanoparticles and its chemistry

Flora Maitim Yrad, Speaker at Nanotechnology conferences
Silliman University, Philippines
Title : Modified synthesis of dextrin-capped gold nanoparticles and its chemistry


Dextrin methodology is an aqueous alkaline chemical process for gold nanoparticle (AuNP) synthesis. Although dextrin-capped AuNPs reportedly demonstrate versatility in some biosensing applications, their synthesis takes 8 long hours of reaction.  A modified method is hereby described that simplified the procedure, equipment, and reduced the reaction time to only one hour. The key features of the modified method are the reversal of the addition of reagents in the original dextrin protocol and the increase of reaction temperature. Optimum synthesis was achieved by sequential neutralization of 50 mL of 2 mM HAuCl4 with 0.5 mL of 10% Na2CO3 and alkaline reduction using selected volumes of 25 g/L dextrin. The AuNPs produced were monodispersed based on dynamic light scattering (DLS) measurements. The surface plasmon resonance band ranged from 517 to 520 nm indicating spherically shaped AuNPs. High resolution transmission electron microscopy (HRTEM) further confirmed the spherical shape with average sizes from 7.3 ± 1.1 to 18.9 ± 1.5 nm, depending on the volume of dextrin. Chemical reactions are hereby proposed to explain the chemistry of AuNP formation based on the alkaline reduction of HAuCl4 with dextrin as the reducing agent.

Audience take-away:

  • The audience will learn an alternative method of producing dextrin-capped gold nanoparticles.
  • The modified method that will be described provides a simpler protocol, shorter reaction time, and less expensive equipment.
  • Chemical reactions are proposed to explain the chemistry of the formation of dextrin-capped AuNPs.


Dr. Flora Yrad studied at the University of San Carlos, Cebu City, Philippines and received her diploma for PhD degree in Chemistry in 2019. She conducted her dissertation research at the Nano-Biosensor Lab of Michigan State University, Michigan, USA under the USAID-STRIDE scholarship and published her works in Diagnostics, 2019, 9, 74 and Silliman Journal, 2020, 61, vol. 2. She is currently teaching at Silliman University, Dumaguete City, Philippines.