Biomolecule-functionalized nanoparticles molecules

Wet preparation of metal nanoparticles and their covalent immobilization onto silicon surface has been surveyed in this manuscript. Thiol-metal interaction can be widely used in order to functionalize the surface of metal nanoparticles by SAM formation. Various thiol molecules have been used for this purpose. The obtained functionalized particles can be purified to avoid the effect of unbounded molecules. On the other hand, hydrogen-terminated silicon surface is a good substrate to be covered by Si-C covalently bonded monolayer and can be functionalized readily by this link formation. Nanomaterials, such as biomolecules or nanoparticles, can be immobilized onto silicon surface by applying this monolayer formation system. 

The fast, sensitive, reliable, and reproducible detection of (bio)molecules including quantification as well as biomolecule localization, the measurement of their interplay with one another or with other species, and the assessment of biomolecule function in bioassays as well as in vitro and in vivo plays an ever increasing role in the life sciences. The vast majority of applications exploit extrinsic fluorophores like organic dyes, fluorescent proteins, and also increasingly QDs, as the number of bright intrinsic fluorophores emitting in the visible and NIR is limited. In the near future, the use of fluorophore-doped nanoparticles is also expected to constantly increase, with their applicability in vivo being closely linked to the intensively discussed issue of size-related nanotoxicity [88]. 

The third group of Au NP-biomolecule interactions are referred to as specific affinity interactions and include nanoparticles functionalized with groups that provide affinity sites for the binding of bio molecules such as proteins and oligonucleotides. 

Finally, the arsenal of synthetic methodologies for the preparation of QDs leads to monolayer- or thin-film-protected nanoparticles with tailored functionalities (see Section 6.2). This enables the tethering of molecular or biomolecular units to the QDs ]49], and also allows the electronic coupling between the photoexcited QDs and the tethered molecules or biomolecules. 

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