Growth in Gels

It has long been observed that very beautiful crystals sometimes develop in gels. Wonderfully fine crystals of sugar frequently grow in ordinary fruit jellies. Many splendid mineral crystals are embedded in silica and appear to have developed while the silica was in the state of a gel. For this geological aspect of the subject, consult the papers of Cornu in the first five volumes of Kolloid-Zeitschrift. The experiments on crystal growth require some time for the proper development of the crystals, but the technique of the method is very simple and easily acquired. 

References Holmes, J. Franklin Inst., 184, 743 (1917) Prat, Kolloid-Zeit., 47, 36 (1929). 

---

The quality of crystals can be significantly improved when grown in gel media. Growth in gel reduces both convection of the protein molecules, thus favouring their slow diffusion to the crystal faces. 

HK Henisch. Crystal Growth in Gels. University Park Pennsylvania State University Press, 1973. 

Sperka, G (1988) Crystal growth in gels - a survey. Progress in Colloid and Polymer Science, 77, 207-210. 

Crystal Growth in Gels OL-1 Sodium silicate gd containing Mi2+,KMn04 above hardened gd. Room temperature, 30 days 77... 

Surveys of growth in gels have been made by Henisch (1988) and Arora (1981). 

The subject of crystal growth in gels was reviewed by Kachi (627). 

One excellent general method to do this is crystal growth in gels of different types, the general principle being that the gel slows down the process and also minimises the number of nucleation sites (sites where the crystals start to grow). One of the reactants can be dissolved in the gel, or the reagents can be separated by a gel in for example a U-tube. Both aqueous and non-aqueous solvents can be used, and the technique has been successfully applied to 3D nets [37,38]. 

Krewson C E, Chung S W, Dai W and Saltzman W M, Cell aggregation and neurite growth in gels of extracellular matrix molecules , Biotechnol. Bioeng., 1994, 43, 555-62. 

---