BIOTECHNOLOGY 63
Investigating manufactured nanoparticles
Characterising the bio-nano interface using QCM technology. By Teodor Aastrup, Diluka Peiris & Daniel Wallinder.
M
anufactured nanoparticles (MNPs) are increasingly
being considered for use in biomedical applications ranging from drug delivery to cellular imaging. Tus, the understanding of MNPs’ interactions with biological systems has become vital for both their safety profile and efficient applications.
Te growing interest on elucidating the impact of physicochemical properties of NPs (e.g. size, surface charge, hydrophobicity, or shape) on their subsequent cellular interactions necessitates the exploration of new technical tools.
Fig. 1. Formation of protein coating and binding of nanoparticles to cell surface.
QCM technology Here we illustrate that these bio- physiochemical interactions can be investigated by Attana´s cell- based quartz crystal microbalance (QCM) technology, a label- free method widely used to study binding between two macromolecules. Te QCM technology is a sensitive balance
capable of measuring changes in mass at a molecular level. An applied AC potential causes the quartz crystal to vibrate at its resonance frequency. As molecules flow over the crystal and bind to their receptor/ ligand the vibration frequency changes. Tis change in frequency is used to characterise real-time, label-free molecular interactions
Typically, one of the two interacting partners is immobilied on a sensor chip surface, and the other is flowed through a microfluidic system in contact with the chip surface.
Binding is revealed in real time as a change of mass at the surface, and the interaction can be characterised in terms of on and off rates (kinetics) and binding strength (affinity).
In the Attana Cell 200, innovative experiments are facilitated, for instance, the study of bimolecular interactions directly on cell surfaces and the utilisation of complex biological
samples including serum(1) .
Tanks to these features, Attana QCM technology allows characterisation of NP interaction in a physiologically relevant environment.
Characterisation of NPs’ interaction with adherent cells Nanoparticles that are taken up in the body will come into contact with extracellular proteins such as blood serum proteins.
Tese proteins can be rapidly absorbed on to the surface of nanoparticles, forming a protein coating refers as ‘protein corona’.
Te protein corona signifies the biological identity of the nanomaterial and alters nanoparticle-cell surface interactions compared to the native nanoparticle.
A new approach A platform based on the Attana QCM based cell biosensor technology, which utilises adherent cells directly grown on the sensor surface has been developed for the characterisation of interactions at the bio-nano interface (2), (3)
.
Fig. 1. shows the formation of protein coating and binding of nanoparticles to cell surface. NPs were dispersed in 10% fetal calf serum.
Serum protein coated NPs were injected over lung epithelial cells grown on sensor surface. Within the figure, (a) and (b) show the binding curves of the same type of NPs either conjugated with COOH groups or NH2 groups resulting net positive or negative surface charge.
www.scientistlive.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92