Exploiting gold nanoparticles for cell manipulation

(Nanowerk News) High-throughput biological devices rely on the transport, attachment and release of various entities in order to conduct millions of tests in a short period of time. A European study utilised nanoparticles made of gold to capture and manipulate living cells, with the ultimate goal to implement this technology in biomedical instrumentation.
The expanding field of nanoscience continuously provides innovative solutions through the use of particles from 1 to 100 nanometres in size. The ability of gold to strongly absorb laser radiation and convert it into heat renders gold nanoparticles an ideal tool for a variety of biological applications. This property has been exploited for selectively destroying cancer cells and for the molecular dissociation of DNA strands.
The EU-funded ‘Multifunctional photothermal gold nanoarrays for cellular manipulation’ (MULTI-PGNAS) project aimed to utilise this technology to develop photo-thermal gold nanoparticle arrays (PGNAs) for the manipulation of living cells. The plan was to coat gold nanoparticles with polyethylene glycol (PEG) moieties and integrin binding peptides which would serve as extracellular matrix (ECM) adhesion sites for cells.
Gold nanoparticles were arranged on glass coverslips and prepared for tissue culture use by chemical treatment with PEG and immobilisation of integrin binding peptides. The MULTI-PGNAS scientists employed laser power to tune the released thermal energy so they could control cell detachment over cell death. Importantly, cells started spreading again as soon as the laser stopped.
Additionally, scientists found that a pulsed, and not continuous, laser was required for targeting single transmembrane receptors without disturbing the rest of the cell.
MULTI-PGNAS technology holds great potential for fundamental research applications such as lab-on-chip systems and various biological devices where release and transport of entities like cells or biomolecules is required. Furthermore, understanding how to control the production of heat confined at the nano-scale could open new avenues of exploitation in nanochemistry, drug release and microfluidics.
Source: Cordis