1 3
Topics in Current Chemistry (2020) 378:12
covalent immobilization or physical adsorption. Several reports demonstrate that
the conformation of enzymes is not heavily harmed when supramolecular methodologies are used [134, 135].
Due to its importance, we highlight in this revision the supramolecular immobilization using the biotin-avidin interactions. Certainly, avidin is a glycoprotein having
four identical subunits that have high specificity and affinity for biotin, resulting in a
strong interaction (K aff ~ 10
15
[136]). Streptavidin, a non-glycosylated tetramer protein, is the most commonly used avidin analog for immobilization through supramolecular interactions [137]. Biotinylated proteins [138], oligonucleotides [139], antibodies [140], and single-stranded DNA [141] have been immobilized on AuNPs and
nanohybrids functionalized with streptavidin to obtain biosensors (Fig. 7).
This methodology has also been used to conjugate gold/iron oxide core–shell
nanoparticles with both chloroperoxidase and glucose oxidase (GOx) through
layer-by-layer assembly using the specific avidin–biotin interactions. The bienzymatic nanoreactor obtained combined the generation of H 2 O 2 in situ from glucose
and oxygen, with facile separation using a magnetic field. The latter had a positive
impact on the reusability of the obtained system. The combination of both enzymes
also enhanced considerably the operational stability of the bioconjugate [142].
Other molecules, such as the family of cyclodextrins, also behave as hosts, and
therefore allow the supramolecular conjugation of NPs caped with cyclodextrins
with adamantane-functionalized biomolecules via inclusion complexes [143].
Other molecules such as ferrocene have also been used as cyclodextrin guests
for the functionalization of modified biomolecules [144]. Assembly of a thiolated
cyclodextrin and a ferrocene derivative has also been reported. The NPs obtained
were used for controlled drug delivery. The noncovalent complex formed between
cyclodextrin and an amphiphilic ferrocene derivative allowed encapsulation of
doxorubicin; the drug may be rapidly released at low pH [145].
Fig. 7 Schematic representation of the supramolecular interaction between biotinylated biomolecules
with NPs capped with streptavidin or avidin
107
Reprinted from the journal
Topics in Current Chemistry (2020) 378:12
covalent immobilization or physical adsorption. Several reports demonstrate that
the conformation of enzymes is not heavily harmed when supramolecular methodologies are used [134, 135].
Due to its importance, we highlight in this revision the supramolecular immobilization using the biotin-avidin interactions. Certainly, avidin is a glycoprotein having
four identical subunits that have high specificity and affinity for biotin, resulting in a
strong interaction (K aff ~ 10
15
[136]). Streptavidin, a non-glycosylated tetramer protein, is the most commonly used avidin analog for immobilization through supramolecular interactions [137]. Biotinylated proteins [138], oligonucleotides [139], antibodies [140], and single-stranded DNA [141] have been immobilized on AuNPs and
nanohybrids functionalized with streptavidin to obtain biosensors (Fig. 7).
This methodology has also been used to conjugate gold/iron oxide core–shell
nanoparticles with both chloroperoxidase and glucose oxidase (GOx) through
layer-by-layer assembly using the specific avidin–biotin interactions. The bienzymatic nanoreactor obtained combined the generation of H 2 O 2 in situ from glucose
and oxygen, with facile separation using a magnetic field. The latter had a positive
impact on the reusability of the obtained system. The combination of both enzymes
also enhanced considerably the operational stability of the bioconjugate [142].
Other molecules, such as the family of cyclodextrins, also behave as hosts, and
therefore allow the supramolecular conjugation of NPs caped with cyclodextrins
with adamantane-functionalized biomolecules via inclusion complexes [143].
Other molecules such as ferrocene have also been used as cyclodextrin guests
for the functionalization of modified biomolecules [144]. Assembly of a thiolated
cyclodextrin and a ferrocene derivative has also been reported. The NPs obtained
were used for controlled drug delivery. The noncovalent complex formed between
cyclodextrin and an amphiphilic ferrocene derivative allowed encapsulation of
doxorubicin; the drug may be rapidly released at low pH [145].
Fig. 7 Schematic representation of the supramolecular interaction between biotinylated biomolecules
with NPs capped with streptavidin or avidin
107
Reprinted from the journal