On inorganic colloids

Kinetics and Catalysis in Microheterogeneous Systems, M. Gr tzel. K. Kalyana-sundaram. Eds.. Surfactant Series 38, Marcel Dekker (1991) (part on micellar catalysis, part on inorganic colloids). 

Iler s contributions, more than those of any other scientist of that period, narrowed the gap. His extensive experimental work and many papers and patents alone would give him a prominent place in the field. However, his major contribution is probably the order he brought to the empirical knowledge that existed prior to 1950. Through the publication of his first book, Colloidal Chemistry of Silica and Silicates, in 1955 (5), he transformed the field from an empirical art with a modicum of science to a science with remnants of art . Researchers soon realized that this was a very valuable and rare book—not only for the specific information on silica, but also for the broad understanding it provided on inorganic colloidal systems in general. 

Most studies of colloid behavior have focused on inorganic colloids, although organic macromolecules and biocolloids have been studied to a limited extent. 

Many metal ions react with water to produce hydrolysis products that are multiply charged inorganic polymers. These may react specifically with negative sites on the colloidal particles to form relatively strong chemical bonds, or they may be adsorbed at the interface. In either case, the charge on the particle is reduced. 

This protocol was extended to other inorganic colloids (e.g., ZnS, PbS), and it was pointed out that such extension paves the way to an electrochemical coding technology for the simultaneous detection of multiple DNA targets based on nanocrystal tags with diverse redox potentials [148]. 

Caruso, R.A., Susha, A. and Caruso, F. (2001) Multilayered titania, silica, and laponite nanopartides coating on polystyrene colloidal templates and resulting inorganic hollow spheres. Chemistry of Materials, 13, 400—409. 

FIGURE 14.5 Multiprotein electrical detection protocol based on different inorganic colloid nanocrystal tracers, (a) Introduction of antibody-modified magnetic beads (b) binding of the antigens to the antibodies on the magnetic beads (c) capture of the nanocrystal-labeled secondary antibodies (d) dissolution of nanocrystals and electrochemical stripping detection (reproduced from [29] with permission). 

Van Moorleghem C, Six L, Degryse F, Smolders E, Merckx R. Effect of organic P forms and P present in inorganic colloids on the determination of dissolved P in environmental samples by the diffusive gradient in thin films technique, ion chromatography, and colorimetry. Anal. Chem. 2011 83 5317-5323. 

Oh, S.J. Cook, D.C. Townsend, H.E. (1998) Characterization of iron oxides commonly formed as corrosion products on steel. Hyper-fine Interactions 112 59-65 Ohmori, M. Matijevic, E. (1992) Preparation and properties of uniform coated inorganic colloidal particles. VII. Silica on hematite. J. Colloid Interface Sci. 150 594-598 Ohta, S. Effendi, S. Tanaka, N. Miura S. (1993) Ultisols of lowland Dipterocarp forest in East Kalimantan, Indonesia. Soil Sci. Plant Nutr. 39 1-12... 

The influence of humic acid on the adsorption of europium onto inorganic colloids as a function of pH. Colloids Surfaces A Physicochemical and Engineering Aspects, 99, 187-199. 

The inorganic colloidal calcium phosphate associated with casein in normal milk dissolves on acidification of milk to pH 4.6 so that if sufficient time is allowed for solution, isoelectric casein is essentially free of calcium phosphate. In the laboratory, best results are obtained by acidifying skim milk to pH 4.6 at 2°C, holding for about 30 min and then warming to 30-35°C. The fine precipitate formed at 2°C allows time for the colloidal calcium phosphate to dissolve (Chapter 5). A moderately dilute acid (1 M) is preferred, since concentrated acid may cause localized coagulation. Acid production by a bacterial culture occurs slowly and allows time for colloidal calcium phosphate to dissolve. The casein is recovered by filtration or centrifugation and washed repeatedly with water to free the casein of lactose and salts. Thorough removal of lactose is essential since even traces of... 

Adsorbed on mixed colloids, (inorganic/organic) Cu2+, Fe203/humic acid ... 

Using preformed sols instead of metal alkoxides as precursors is an attractive alternative in sol-gel preparation because recent advances in inorganic colloidal dispersions allow some control over the characteristics of the starting sols [11]. Often a colloidal suspension of sol particles is stabilized (i.e. prevented from flocculation) by pH adjustment. Thus, pH of the solution, which can be changed by the addition of either acid or base, is the single most important parameter in obtaining a gel from preformed sols. Other parameters that can impact on gel quality are the size and concentration of the starting sol particles. 

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