Effect of various precipitants on the nucleation rate of tetragonal hen egg-white lysozyme crystals in an AC external electric field

Technique for High-Quality Protein Crystal Growth by Control of Subgrain Formation under an External Electric Field

“…Furthermore, analyzing the strength of an external electric field necessary to control such a change in the nucleation thermodynamically, we have revealed that it is estimated to be 10 4 V/cm, which is significantly larger than that used experimentally (800 V/cm) [51]. In our experimental arrangement, the large difference between the electrical permittivities of the solution and the oil plays an important role in the formation of a large electric potential gradient at the inner surface of a drop of the solution in oil [52][53][54]. This is known as the electric double layer (EDL).…”

“…The electrode surface dimension was 12 × 45 mm 2 . It is considered that a large electric potential difference generates at the interface between the plastic cell and the protein solution, leading to the formation of an EDL, as described in our previous works [51,53,54]. Thus, tetragonal HEW lysozyme crystals grown on the sides of electrodes were used to obtain XRD rocking-curve profiles.…”

Recent Insights into the Crystallization Process; Protein Crystal Nucleation and Growth Peculiarities; Processes in the Presence of Electric Fields

“…In a series of works, Koizumi et al [18][19][20][21][22][23][24][25][26][27][28][29] have achieved a breakthrough in EF-promotion of protein crystal nucleation. Previous experience and theoretical considerations has given them reason to realize that the difference in electrical permittivity of liquid and solid must be the factor that defines the degree of change (appearing due to the external EF) in the chemical potential, ∆µ (nucleation driving energy).…”

“…The greater the ionic strength of the solution (dependent on the precipitant used), the thinner the electric double layer at the solution drop/sealing oil interface, and the stronger the EF-effect exerted on the supersaturation (being a crystal nucleation driving factor) [20]. The effect of an external ac-EF on the HEWL crystal nucleation rate increases with the increase in the concentration of the precipitant used (in the case considered, the precipitant is NiCl 2 ).…”

“…Pioneered by Aubry's group [4,5] some 20 years ago, protein crystallization under EF attracts an increasing attention, becoming a mature scientific branch today. Major contributions in this research field have been made by the teams of Moreno [6][7][8][9][10][11][12][13][14][15][16][17], Koizumi [18][19][20][21][22][23][24][25][26][27][28][29], Veesler [30][31][32][33], etc. (the list is not exhaustive).…”