Adsorption behavior of ferritin and buffer components, buffer agents and salts, onto silane-coupled silicon substrate.
Fixation of ferritin using amino-silane modified substrates is effective, but salt and alkali ions of the buffer can contaminate substrates, inhibiting the sensing and fabrication of nano-electronic devices. To avoid adsorption of salts and alkali ions, buffer solutions have been replaced by pure water or alkali-metal-ion-free buffer. However, proteins in such solutions are sometimes denatured. Therefore, we developed a substrate which adsorbs ferritin but does not adsorb contaminants such as salts and alkali metal-ions contained in the buffer. Adsorption of ferritin was achieved by using a buffer with a high ion strength, such as PBS buffer, because the Debye length becomes shorter with increased ion strength due to intermolecular force even when the substrate has no positive charge. The combination of high coverage methyltrimethoxysilane (MTMS)-coupled silicon substrate and PBS buffer solution is effective for adsorption of ferritin while not adsorbing buffer components such as contaminants and/or salts on the silicon substrate.
Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
Megumi
M
Fukuta
Ichiro
I
Yamashita
D000327:Adsorption; D000818:Animals; D002021:Buffers; D002244:Carbon / Q000737:chemistry; D005293:Ferritins / Q000378:metabolism*; D006531:HEPES; D006736:Horses; D057927:Hydrophobic and Hydrophilic Interactions; D017953:Isocyanates / Q000737:chemistry; D008741:Methyl Methanesulfonate / Q000031:analogs & derivatives / Q000737:chemistry; D018625:Microscopy, Atomic Force; D056951:Photoelectron Spectroscopy; D012492:Salts / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry; D012996:Solutions; D013455:Sulfur / Q000737:chemistry; D013499:Surface Properties; D014867:Water / Q000737:chemistry
C514436:3-isocyanatopropyl trimethoxysilane; D002021:Buffers; D017953:Isocyanates; D012492:Salts; D012821:Silanes; D012996:Solutions; D014867:Water; C014674:methyl methanethiosulfonate; D013455:Sulfur; D002244:Carbon; D005293:Ferritins; D012964:Sodium; D008741:Methyl Methanesulfonate; D006531:HEPES; D012825:Silicon