Progressive Local Accumulation of Self-Assembled Nanoreactors in a Hydrogel Matrix through Repetitive Injections of ATP

Abstract

Cellular functions are regulated with high spatial control through the local activation of chemical processes in a complex inhomogeneous matrix. The development of synthetic macroscopic systems with a similar capacity allows fundamental studies aimed at understanding the relationship between local molecular events and the emergence of functional properties at the macroscopic level. Here, we show that a kinetically stable inhomogeneous hydrogel matrix is spontaneously formed upon the local injection of ATP. Locally, ATP templates the self-assembly of amphiphiles into large nanoreactors with a much lower diffusion rate compared to unassembled amphiphiles. The local depletion of unassembled amphiphiles near the injection point installs a concentration gradient along which unassembled amphiphiles diffuse from the surroundings to the center. This allows for a progressive local accumulation of self-assembled nanoreactors in the matrix upon repetitive cycles of ATP injection separated by time intervals during which diffusion of unassembled amphiphiles takes place. Contrary to the homogeneous matrix containing the same components, in the inhomogeneous matrix the local upregulation of a chemical reaction occurs. Depending on the way the same amount of injected ATP is administered to the hydrogel matrix different macroscopic distributions of nanoreactors are obtained, which affect the location in the matrix where the chemical reaction is upregulated.

Short peptide-based cross-β amyloids exploit dual residues for phosphoesterase like activity

“…The cationic guanidinium groups were expected to bind the anionic HPNPP and facilitate the cleavage of the phosphoester bond. [24][25][26][27][28][29][30][31][32] The imidazole moiety of histidine is known to Please do not adjust margins Please do not adjust margins facilitate phosphoester hydrolysis by acting as a general acid/base catalyst or by acting as a nucleophile. 33,34 The rate of hydrolysis was monitored with the help of UV-Vis spectroscopy by the change of absorbance at 405 nm.…”

Persistent ATP‐Concentration Gradients in a Hydrogel Sustained by Chemical Fuel Consumption

“…Recently, we have shown that a hydrogel is an attractive matrix for adding a spatial dimension to supramolecular processes. [39,40] The presence of a polymer network blocks mass transport by convection and leaves diffusion as the principal mechanism for mass transport. Because diffusion strongly depends on size, the mass transport of small molecules (like A, ATP/ADP, PCr, etc.)…”

“…This regarded the necessity to produce and consume ATP with spatial control. Recently, we have shown that a hydrogel is an attractive matrix for adding a spatial dimension to supramolecular processes [39, 40] . The presence of a polymer network blocks mass transport by convection and leaves diffusion as the principal mechanism for mass transport.…”

Regulating Spatial Localization and Reactivity Biasness of DNAzymes by Metal Ions and Oligonucleotides

“…[42] Now the triangular placement of the gels inside the hybridization chamber ensure that one of the half will have more concentration of only the substrate of GQ-1, H 2 O 2 + ODA and other half contains the substrate along with the inhibitor Hg 2 + , specially concentration of Hg 2 + will be more near the gel C. It is to be noted here triangular organization of the gels and bifurcating flow behavior along with composition of the diffusing molecules has also been demonstrated in previous literature report. [43][44][45][46] Now, the evenly dispersed catalytic GQ-1 bead will slowly start to settle down in the glass surface. After 2 h, we counted the number of beads along the straight line connected region through gel B and C as near gel B, the concentration of the substrates will be more, whereas near gel C, it will be substrates along with the inhibitor Hg 2 + .…”