THEORETICAL & PHYSICAL CHEMISTRY INSTITUTE
 
  Materials Synthesis and Physical Chemistry
  Carbon nanostructures and two-dimensional nanomaterials
  Block copolymer synthesis and self-assembled nanostructures
  Nanostructured biomaterials
  Énvestigations using vibrational spectroscopy/microscopy (Raman and infrared)
AFM/Raman correlative microscopy

  Clay minerals and clay-based hybrid materials
  Low dimensional Hybrid Materials
  Synthesis and physicochemical properties of advanced organic-inorganic materials
  Design and development of Metal Organic Frameworks and/or Covalent Organic Frameworks
  Design and construction of artificial photosynthetic systems for the conversion of solar energy to fuels

Material Synthesis and Physical Chemistry

Advanced physicochemical characterization and optimization

A broad range of advanced experimental methods are developed and used to study the nanostructure, dynamics and molecular interactions of biomaterials. Particle solutions and dispersions, complex fluids, gels and interfaces can be investigated. Advanced applications of microrheology on biopolymer fluids and small angle scattering on nanoparticles and hierarchical soft systems are unique at the national level. These methods allow for the detailed characterization of the physicochemical properties and in addition provide the necessary input for the optimization and the refinement of the designed biomaterials.

A video particle tracking microrheology instrument and software for image processing and data analysis have been developed at the TPCI/NHRF. With this optical technique the viscoelasticity of complex fluids and soft gels as a function of length scale can be extracted. An image analysis software extracts the trajectories of the thermally diffusing probe particles within the biomaterials and statistical description of the ensemble and individual particles’ diffusion are obtained. A numerical analysis software is used to provide rheological parameters such as viscosity, storage modulus and viscous modulus.

Small angle scattering methods are capable of resolving the morphology in solutions, dispersions, complex fluids and hydrogels at length scales between 1 and 100 nm. There is long experience in using large-scale facilities for small angle neutron and X-ray scattering. Small angle neutron scattering in particular has high structural resolving power because of the ability to use contrast variation and contrast matching methods. Software for data analysis and optimization has been developed and an extended library of routines (form factors, structure factors, hierarchical generic models) for employing scattering models and fitting experimental data is available (Monte Carlo minimization etc). Advanced stochastic calculations are employed such as Bayesian analysis to resolve parameters’ interdependencies.

A surface plasmon resonance instrument has been developed to study the adsorption kinetics and the formation of biopolymer films and multilayers at metal/water interfaces. Software has been developed for the goniometer control, data acquisition and data analysis/optimization at the TPCI/NHRF. Quartz crystal microbalance with dissipation (open-QCM) is used for complementary measurements. A homemade set-up for contact angle measurements (including image acquisition and analysis software) is used for the extraction of static, advancing and receding contact angle and of the sessile drop profile. Neutron reflectivity can be performed at large scale facilities to resolve the density profile of the interfaces. Software for data analysis and optimization for the extraction of the interface characteristics is available. Formation, response to external stimuli and stability of polymer, biopolymer, protein and mixed films are characterized.

Physicochemical characterization protocols have been developed and optimized. Fluorescence spectroscopy is used to extract the binding constants between nanoparticles and nutraceuticals by fluorescence quenching and fluorescence enhancement. UV-Vis spectroscopy is applied for the evaluation of nutraceutical encapsulation and degradation. The nanoparticles’ surface hydrophobicity is characterized by fluorescence spectroscopy. Extraction of protein secondary structure (α-helix, β-sheet etc) is achieved by attenuated total reflection-infrared spectroscopy (ATR-FTIR) and peak deconvolution with custom-made software.

 

Key publications

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Carbohydr. Polym. 2019, 218, 218

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Food Hydrocoll. 2016, 61, 201

   

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Carbohydr. Polym. Tech. Appl. 2021, 2, 100075

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Carbohydr. Polym. 2016, 153, 196
Carbohydr. Polym. 2023, 303, 120478

   
   
   

 

Recent publications (since 2013)

Physicochemical characterization and optimization

Protein-induced transformation of unilamellar to multilamellar vesicles triggered by a polysaccharide
Carbohydr. Polym. 2023, 303, 120478

Physicochemical properties of electrostatically crosslinked carrageenan/chitosan hydrogels and carrageenan/chitosan/Laponite nanocomposite hydrogels
Int. J. Biol. Macromol. 2023, 225, 565

Sustainable production of novel oleogels valorizing microbial oil rich in carotenoids derived from spent coffee grounds
J. Agric. Food Chem. 2022, 70 (35), 10807

Length-scale dependence of pH- and temperature-response of PDMAEMA-b-PHPMA block copolymer self-assemblies in aqueous solutions
Polymer 2022, 239, 124428

Formation and physicochemical properties of glycogen phosphorylase in complex with a cationic polyelectrolyte
Int. J. Biol. Macromol. 2022, 206, 371

Star Polyelectrolytes with Mixed Arms of PDMAEMA and POEGMA: Self-Assembly and Coassembly with Insulin
Macromol. Chem. Phys. 2022, 223, 2200008

Effects of Polymer Block Length Asymmetry and Temperature on the Nanoscale Morphology of Thermoresponsive Double Hydrophilic Block Copolymers in Aqueous Solutions
Macromolecules 2021, 54, 7298

Amphiphilic AxBy mikto‐arm star copolymers with PLMA and POEGMA arms: Self‐assembly and drug encapsulation
Polym. Sci. 2021, 59, 775

Formation of Uni-Lamellar Vesicles in Mixtures of DPPC with PEO-b-PCL Amphiphilic Diblock Copolymers
Polymers 2021, 13, 4

Lamellarity and size distributions in mixed DPPC/amphiphilic poly(2-oxazoline) gradient copolymer vesicles and their temperature response
Chem. Phys. Lipids 2021, 234, 105008

Combining particle tracking microrheology and viscometry for the study of DNA aqueous solutions
Biopolymers 2020, 111, e23353

Functional surfaces of laser-microstructured silicon coated with thermoresponsive PS/PNIPAM polymer blends: Switching reversibly between hydrophilicity and hydrophobicity
Appl. Surf. Sci. 2020, 527, 146841

Effect of layer charge and charge distribution on the formation of chitosan - smectite bionanocomposites
Appl. Clay Sci. 2020, 190, 105583

Block Copolymer Nanosystems Encapsulating Magnetic Nanoparticles and Drug
J. Nanosci. Nanotechnol. 2020, 20, 1

Reorganizations inside thermally stabilized protein/polysaccharide nanocarriers investigated by small angle neutron scattering
Carbohydr. Polym. 2019, 218, 218

Surface Plasmon Resonance study of adhesion kinetics of smectites on the Au/water interface: clay and organo-clay film formation
Appl. Clay Sci. 2019, 175, 1

Thin films of PS/PS-b-PNIPAM and PS/PNIPAM polymer blends with tunable wettability
J. Polym. Sci. B Polym. Phys. 2019, 57, 670

Association and Internal Morphology of Self-Assembled HPPhOx/BSA Hybrid Nanoparticles in Aqueous Solutions
J. Phys. Chem. B 2018, 122, 7426

Hydrolyzed poly(2-plenyl-2-oxazoline)s in aqueous media and biological fluids
Macromol. Chem. Phys. 2018, 219, 1800047

Adsorption of lysozyme on pH-responsive PBA-b-PAA polymeric nanoparticles: stopped-flow SAXS and ITC study
Colloid Polym. Sci. 2018, 296, 1183

Formation of complexes in aqueous solutions of amphiphilic triblock polyelectrolytes of different topologies and an oppositely charged protein
Soft Matter 2018, 14, 2860

The High Intensity Option of the SANS Diffractometer KWS-2 at JCNS - Characterization and Performance of the New Multi-MHz Detection System
J. Appl. Crystallogr. 2018, 51, 323

Viscosity Transitions Driven by Thermoresponsive Self-Assembly in PHOS-g-P(PO-r-EO) Brush Copolymer
Macromolecules 2018, 51, 1644

Thermal response of self-organization in an amphiphilic triblock polyelectrolyte and the influence of the globular protein lysozyme"
Eur. Polym. J. 2018, 99, 49

Tuning the solution organization of cationic polymers through interactions with bovine serum albumin
Phys. Chem. Chem. Phys., 2017, 19, 18471

Self-assembly of poly(ethylene glycol-b-phenyl oxazoline) diblock copolymers in aqueous media and their interactions with proteins
Colloid Polym. Sci. 2017, 295, 1359

Amphiphilic poly(2-oxazoline) copolymers as self-assembled carriers for drug delivery applications
Eur. Polym. J. 2017, 88, 516

Micelles from HOOC-PnBA-b-PAA-C12H15 diblock amphiphilic polyelectrolytes as protein nanocarriers
Biomacromolecules 2016, 17, 3816

Thermoresponsive behavior of micellar aggregates from end-functionalized PnBA-b-PNIPAM-COOH block copolymers and their complexes with lysozyme
Soft Matter 2016, 12, 6547

Scattering investigation of multiscale organization in aqueous solutions of native xanthan
Carbohydr. Polym. 2016, 153, 196

Particle tracking microrheology of the power-law viscoelasticity of xanthan solutions
Food Hydrocoll. 2016, 61, 201

Kinetics of temperature response of PEO-b-PNIPAM-b-PAA triblock terpolymer aggregates and of their complexes with lysozyme
Polymer 2016, 83, 111

Tuning the instrumental resolution using chopper and TOF data acquisition at the high-intensity / extended Q-range SANS diffractometer KWS-2 of the JCNS
J. Appl. Crystallogr. 2015, 48, 1849

Micellar and fractal aggregates formed by two triblock terpolymers with different arrangements of one charged, one neutral hydrophilic and one hydrophobic block
Polymer 2015, 63, 134

Thermoresponsive aggregation of PS-PNIPAM-PS triblock copolymer: A combined study of light scattering and small angle neutron scattering
Eur. Polym. J. 2014, 56, 59

Thermoresponsive transition of a PEO-b-PNIPAM copolymer: From hierarchical aggregates to well defined ellipsoidal vesicles
Polymer 2013, 54, 6373

 

 

 

 

 

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