How does the pH level influence the preservation of L-histidine when adsorbed onto saponite under UV irradiation?

Label:chem

Topic
The pH level can significantly affect the adsorption and stability of organic molecules on mineral surfaces. This study investigates how different pH levels influence the preservation of L-histidine when adsorbed onto saponite under simulated Martian UV conditions.

From: "Photodegradation of the biomarker L-histidine induced by edge sites of a clay mineral in the Martian harsh UV environment", Icarus, Volume 442, December 2025, 116757
Answer
The study found that L-histidine adsorbed onto saponite at acidic pH (pH 4) degrades faster under UV irradiation compared to when adsorbed at basic pH (pH 9.6). This suggests that the adsorption mechanism at acidic pH, involving both intercalation and edge interactions, leads to a more rapid degradation due to the photocatalytic effect of the clay's edge sites. At basic pH, the slower degradation rate indicates that the edge interactions through hydrogen bonding provide some protection against UV-induced degradation. Therefore, the pH level plays a crucial role in determining the preservation of L-histidine on saponite under UV radiation.
Return to Home Chemical List
Knowledge you may be interested in
What are the different adsorption mechanisms of L-histidine onto saponite at acidic and basic pH levels? How does the clay mineral saponite affect the photodegradation of the biomarker L-histidine under simulated Martian UV conditions? What therapeutic strategies can be developed based on the F. nucleatum-GSH axis in gastric cancer? Can the abundance of Fusobacterium nucleatum in gastric cancer tissues serve as a diagnostic biomarker? What is the mechanism by which Fusobacterium nucleatum depletes glutathione (GSH) in gastric cancer cells? What is the relationship between Fusobacterium nucleatum infection and glutathione (GSH) levels in gastric cancer (GC)? How do the concentrations of SOD1, SOD3, and 8-OHdG in amniotic fluid (AF) change with gestational age? What are the roles of superoxide dismutase isoforms (SOD1 and SOD3) and glutathione (GSH) in amniotic fluid (AF) during fetal gastrointestinal development? What role does melatonin play in regulating circadian rhythms and cardiovascular health? How was the study designed to minimize bias in the analysis of melatonin use and cataract risk? What is the role of isocyanate additives in asphalt modification? How do isocyanate additives affect the aging behavior of asphalt? How does polyurethane prepolymer (PUP) modify asphalt? What are the limitations of Polyurethane Prepolymer (PUP)-modified asphalt? How does polyurethane (PU) modify asphalt? What is the significance of amide bonds in pharmaceutical compounds? What are the challenges associated with traditional methods of amide synthesis? What are the advantages of using a twin-screw extruder for the synthesis of APIs like teriflunomide and moclobemide? What were the specific conditions used for the synthesis of teriflunomide and moclobemide using twin-screw extrusion? What role does miscanthus biomass play in the synthesis of moclobemide?