the group is in the conjugate acid form if the ph of the solution is less than the pka (protonated). q3 what happens if the pka value is higher than the ph value? we can predict whether a molecule will be protonated or deprotonated based on the connection between its pka and the ph ...
Positive surface charge comes from protonated basic groups (amino/imino or pyridinium groups [36]), while negative charge comes from deprotonated acidic groups (carboxyl or sulphate groups [55]). In our previous work [52], we chose an indirect way to mimic the effect of pH in order to ...
Almost all known pH-responsive antibodies sense pH due to histidine residues within their variable regions. pKa value of the histidine side chain is about 6; thus, at pH below 6.0, the histidine side chain is mostly protonated, whereas, at physiologic pH 7.4, it is deprotonated. It was show...
Absorption and fluorescence spectra of the protonated and deprotonated forms of ACMA (A1324) are quite similar. This observation, and the listed pKa value, are reported in published references. Accumulation of the probe in the presence of transmembrane pH gradients results in fluo...
Peptide conformation at low (left) and high (right) pH: colour codes: W (orange), Y (light orange), S (cyan), R (red), protonated cationic H (red) and deprotonated neutral and aromatic H (yellow) (Supplementary Movie 1). Full size image ...
To validate that our screen lead to a pH stability improvement, we tested the change in excitation ratio between the protonated (405 nm) and deprotonated (488 nm) state (Supplementary Fig. 1). We therefore examined the most stable clone identified in each round of screening using flow cy...
Amino groups present on chitosan get protonated towards acidic pH (below the pKa value of chitosan 6.2) and repulsion between them causes expansion/swelling of the system thus pH-dependent gelling phenomenon is observed with chitosan [28]. But Nazar et al. synthesized thermosensitive in situ nasal...
Indeed, in the wild type ESR at alkaline pH, where His57 is deprotonated, the rate of the M state formation is faster [30,32,33]. The positive charge on the protonated His57 interferes with the proton transfer from the Schiff base to the primary acceptor Asp85. Elimination of His57 ...
bacterial cells. According to the well-known theory of dicationic bridges, carboxyl and amine surface groups are involved in the formation of aggregates. Partially deprotonated carboxyl groups and protonated amino groups are not able to form bridges between (bio)colloids. After yeast centrifugation ...
By increasing or decreasing the pH (depending on the selection of the pH-sensitive groups) the amido gellant is either protonated or deprotonated. Thus, by changing the pH of the solution, the solubility and the viscosity building behaviour of the amido gellant can be controlled. By careful ...