Imperial College London

DrLeonoraVelleman

Faculty of Natural SciencesDepartment of Chemistry

Research Associate
 
 
 
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Contact

 

l.velleman

 
 
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Location

 

ChemistrySouth Kensington Campus

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Summary

 

Summary

Plasmonic nanoparticle assembly at liquid-liquid interfaces

The three most significant challenges facing biosensing are inaccuracy, insensitivity, and low-throughput detection. One technique that is capable of facing these challenges is Surface Enhanced Raman Scattering (SERS) which has demonstrated potential for extreme sensitivity (single molecule detection) and rapid, multiple-analyte detection within complex mixtures. Early stage diagnosis of disease requires the detection of trace amounts of analyte in multi-component biological samples (blood, urine, saliva). It is therefore particularly important for sensors to reach the single-molecule detection limit. Further, the ability to analyse biological samples without separation or other treatment steps is a crucial advantage of SERS.

My approach involves the electrotuneable self-assembly of plasmonic nanoparticles at a liquid-liquid interface for SERS detection, overcoming the severe limitations of current sensors (sensitivity, specificity and speed). The positioning of nanoparticles at the interface is electrochemically controlled in a precise manner to maximise the Raman signal. Additionally I am investigating shaped nanoparticles, such as stars and ellipsoids, to exploit the enormous Raman enhancements observed at sharp metallic tips and push the sensitivity towards single-molecule detection limits. Due to the versatility of this system it can be adapted to any disease or virus where the related biomarker is known.

Mini bio

  • Postdoctoral Research Associate, Department of Chemistry, Imperial College London. Supervisor: Dr Joshua Edel
  • Postdoctoral Research Associate, Institute for Frontier Materials, Deakin University. Supervisor: Prof Lingxue Kong
  • Postdoctoral Research Associate, School of Chemical and Physical Sciences, Flinders University. Supervisors: Prof Joe Shapter, Prof Justin Gooding
  • PhD in Chemistry, School of Chemical and Physical Sciences, Flinders University. Supervisors: Prof Joe Shapter, Dr Dusan Losic
  • BSc in Nanotechnology (Honours), Flinders University

Publications

Journals

Lauri A, Velleman L, Xiao X, et al., 2017, 3D Confocal Raman Tomography to Probe Field Enhancements inside Supercluster Metamaterials, Acs Photonics, Vol:4, ISSN:2330-4022, Pages:2070-2077

Velleman L, Scarabelli L, Sikdar D, et al., 2017, Monitoring plasmon coupling and SERS enhancement through in situ nanoparticle spacing modulation., Faraday Discuss, Vol:205, ISSN:1359-6640, Pages:67-83

Turek VA, Francescato Y, Cadinu P, et al., 2016, Self-Assembled Spherical Supercluster Metamaterials from Nanoscale Building Blocks, Acs Photonics, Vol:3, ISSN:2330-4022, Pages:35-42

Velleman L, Sikdar D, Turek VA, et al., 2016, Tuneable 2D self-assembly of plasmonic nanoparticles at liquid| liquid interfaces, Nanoscale, Vol:8, ISSN:2040-3364, Pages:19229-19241

She X, Chen L, Velleman L, et al., 2015, Fabrication of high specificity hollow mesoporous silica nanoparticles assisted by Eudragit for targeted drug delivery, Journal of Colloid and Interface Science, Vol:445, ISSN:0021-9797, Pages:151-160

More Publications