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Updated: Feb 6, 2026
09:27
Protein Crystallization for X-ray Crystallography
Published on: January 16, 2011
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Diffusion of Proteins across Silica Colloidal Crystals
Patricia Anne A Ignacio-de Leon1, Yulia Eygeris1, Robert Haynes1
1Department of Chemistry , University of Utah , 315 S 1400 E , Salt Lake City , Utah 84112 , United States.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 9, 2018
Summary
Sintered silica colloidal crystals show size and shape selectivity for protein diffusion, making them promising for separations. Their nanopore tortuosity, not surface interactions, drives this selectivity.
Area of Science:
- Materials Science
- Nanotechnology
- Biophysics
Background:
- Protein separation is crucial in biotechnology and medicine.
- Developing efficient nanoporous membranes is an ongoing challenge.
- Understanding diffusion through nanopores informs membrane design.
Purpose of the Study:
- To investigate protein diffusion through sintered silica colloidal crystals.
- To evaluate the size and shape selectivity of these nanoporous membranes.
- To determine the factors influencing protein transport and separation.
Main Methods:
- Studied diffusion of lysozyme, hemoglobin, and albumin through silica colloidal crystals.
- Utilized crystals with varying nanopore sizes (7.5, 19, 27 nm).
- Analyzed protein transport rates and selectivity based on pore characteristics.
Main Results:
- Exhibited size selectivity with 7.5 and 19 nm pores, attributed to nanopore tortuosity.
- Demonstrated shape selectivity for proteins of similar molecular weights in 19 nm pores.
- Larger 27 nm pores increased transport rates but reduced selectivity.
- High-temperature sintering minimized protein-surface interactions, making size and shape dominant factors.
Conclusions:
- Sintered silica colloidal crystals offer tunable nanopore sizes for protein separation.
- These materials exhibit significant size and shape selectivity, driven by pore geometry.
- Promising for developing advanced nanoporous membranes with minimal fouling for protein separations.
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