3 research outputs found
Exploring Nonspecific Protein Adsorption on Lignocellulosic Amphiphilic Bicomponent Films
In this contribution, we explore
the interaction of lignocellulosics
and proteins aiming at a better understanding of their synergistic
role in natural systems. In particular, the manufacturing and characterization
of amphiphilic bicomponent thin films composed of hydrophilic cellulose
and a hydrophobic lignin ester in different ratios is presented which
may act as a very simplified model for real systems. Besides detailed
characterizations of the films and mechanisms to explain their formation,
nonspecific protein adsorption using bovine serum albumin (BSA) onto
the films was studied using a quartz crystal microbalance with dissipation
(QCM-D). As it turns out, the rather low nonspecific protein adsorption
of BSA on cellulose is further reduced when these hydrophobic lignins
are incorporated into the films. The lignin ester acts in these blend
films as sacrificial component, probably via an emulsification mechanism.
Additionally, the amphiphilicity of the films may prevent the adsorption
of BSA as well. Although there are some indications, it remains unclear
whether any kind of protein interactions in such systems are of specific
nature
Designing Hydrophobically Modified Polysaccharide Derivatives for Highly Efficient Enzyme Immobilization
In
this contribution, a hydrophobically modified polysaccharide
derivative is synthesized in an eco-friendly solvent water by conjugation
of benzylamine with the backbone of the biopolymer. Owing to the presence
of aromatic moieties, the resulting water-soluble polysaccharide derivative
self-assembles spontaneously and selectively from solution on the
surface of nanometric thin films and sheets of polystyrene (PS). The
synthetic polymer modified in this way bears a biocompatible nanolayer
suitable for the immobilization of horseradish peroxidase (HRP), a
heme-containing metalloenzyme often employed in biocatalysis and biosensors.
Besides the detailed characterization of the polysaccharide derivative,
a quartz crystal microbalance with dissipation (QCM-D) and atomic
force microscopy (AFM) are used to investigate the binding efficiency
and interaction of HRP with the tailored polysaccharide interfaces.
Subsequent enzyme activity tests reveal details of the interaction
of HRP with the solid support. The novel polysaccharide derivative
and its use as a material for the selective modification of PS lead
to a beneficial, hydrophilic environment for HRP, resulting in high
enzymatic activities and a stable immobilization of the enzyme for
biocatalytic and analytic purposes
Surface-Sensitive Approach to Interpreting Supramolecular Rearrangements in Cellulose by Synchrotron Grazing Incidence Small-Angle X‑ray Scattering
The supramolecular rearrangements
of biopolymers have remained
difficult to discern. Here, we present a versatile approach that allows
for an <i>in situ</i> investigation of two major types of
rearrangements typically observed with cellulose, the most abundant
biopolymer on earth. Model thin films were employed to study time-resolved
pore size changes using <i>in situ</i> grazing incidence
small-angle X-ray scattering (GISAXS) during regeneration and drying