Iron Oxide Nanoparticles: An Inorganic Phosphatase

Abstract

Phosphorus is one of the most important macronutrients for the primary production. The transformation of dissolved organic phosphorus in the environment and its contribution to biological production in the different ecosystems is still a mystery. Recently, it was demonstrated that phosphate ester can be rapidly hydrolyzed in solutions containing iron oxide nanoparticles with enzyme kinetics. The catalyst is sensitive to temperature and pH changes and inhibited by tetrahedral oxyanions with an order of PO 4 < MoO 4 < WO 4. The oxo-Fe structure in the iron oxide nanoparticles, like the metal center of natural phosphatase (e.g., purple acid phosphatase, PAP), might contribute to the observed catalytic activity. Iron oxide nanoparticles are very common and widely exist in the current earth environment, and phosphate esters are the main component of dissolved organic phosphorus in soil and waters. It is expected that iron oxide nanoparticles in aqueous environments, as an inorganic phosphatase, play a critical role for the phosphorus transformation from the view of the phosphorus cycle.

The “Water Problem”(sic), the Illusory Pond and Life’s Submarine Emergence—A Review

“…The nanochemistry and nanotechnology literature appears to have passed these complainants by! In AVT’s defense redox catalysis and polymerization can be promoted within nanometer-sized pores and interlayers such as to be found in layered double hydroxides, including fougerite (~green rust), silica films, amyloid and peptide nests [ 72 , 193 , 194 , 195 , 196 , 197 , 198 , 199 , 200 , 201 , 202 , 203 , 204 , 205 , 206 , 207 , 208 , 209 , 210 , 211 , 212 , 213 , 214 , 215 , 216 ]. Moreover, it should be recalled that the AVT is the only theory which proposes a viable and explicit mechanism for the generation of out-of-equilibrium pyrophosphates as we will address in the next section.…”

“…Either way, many of the research challenges for the hypothesized role(s) of fougerite—dosed with various trace elements and anions—are similar. Such research addressing the submarine acid v. alkaline milieu calls for the further employment of tried-and-tested microfluidic and nano-crystallographic techniques [ 192 , 201 , 202 , 203 , 204 , 205 , 206 , 207 , 224 , 254 , 296 , 297 , 298 , 299 , 300 , 301 , 302 , 310 , 327 , 328 , 329 , 330 , 331 , 332 , 333 , 334 , 335 , 336 , 337 , 338 ]. We enumerate some possible developments from, expectations of, and tests for, the AVT below:…”

On the why's and how's of clay minerals' importance in life's emergence

“…A superposition of phosphates in GR2-type interstitial di-layers comparable to that of sulphates would obviously be particularly pertinent in the framework of emergence of life hypotheses since the strongly lowered water activity in the interstitial spaces would necessarily displace the PP i /P i equilibrium towards higher proportions of the condensed pyrophosphates. Pyrophosphates, once formed, hydrolyse only sluggishly and take in the range of a hundred hours to resume equilibrium proportions if transferred back into bulk water (von Wazer et al, 1955;Huang, 2018Huang, , 2019. Of course, to be of use as a vector of free energy, these pyrophosphate molecules would need to be transported to where the ancestral entropy-lowering processes would have occurred.…”

What are inorganic nanozymes? Artificial or inorganic enzymes

“…2,3 Are these inorganic nanomaterials with enzyme-like characteristic artificial enzymes, 4,5 or are they just newly discovered inorganic enzymes? [6][7][8] Examples of inorganic nanozymes…”