7262-40-0

Upstream product

• 98-88-4 benzoyl chloride 
• 2321-07-5 fluorescein 
• 85-44-9 phthalic anhydride 
• 2513-33-9 2-(2,4-dihydroxybenzoyl)benzoic acid 
• 65-85-0 benzoic acid 

Relevant academic research and scientific papers

NANOPARTICLES BASED METHOD FOR SCREENING ENZYME OR MICROORGANISM

A nanoparticle comprises water-insoluble polymer matrix and an indicator constituent(s), wherein the indicator constituent(s) is released from the nanoparticle only when the polymer matrix is degraded or broken, and then an indicative effect is triggered

Cooperative hydrolysis of aryl esters on functionalized membrane surfaces and in micellar solutions

Catalytic hydrolysis of peptides, proteins, phosphates or carboxylate esters in nature is catalysed by enzymes, which are efficient, fast and selective. Most of the hydrolytic chemical catalysts published so far mimic the active site of enzymes and contain metal complexes and amino acid residues. Their synthesis can be laborious, while the hydrolytic activity is still limited compared to enzymes. We present an approach that uses fluid membranes of vesicles and micelles as a support for amphiphilic additives, which cooperatively cleave aryl ester bonds. The membrane anchored bis-Zn(ii)-complex 1 is hydrolytically active and hydrolyses fluorescein diacetate (FDA) with a second order rate constant (k2) of 0.9 M-1 s-1. The hydrolytic activity is modulated by co-embedded membrane additives, bearing common amino acid side chain functional groups. With this approach, the hydrolytic activity of the system is enhanced up to 16 fold in comparison with cyclen 1 (k2 = 14.7 M-1 s-1). DOPC and DSPC lipids form at room temperature fluid or gel phase membranes, respectively. Omitting the lipid, micellar solutions were obtained with hydrolytic activity reaching k2 = 13.4 M-1 s-1. It is shown that cooperative hydrolysis is favoured in fluid membranes and micelles, allowing the active moieties to arrange freely. The embedding and dynamic self-assembly of membrane active components in fluid membranes and micelles provide facile access to hydrolytically active soft interfaces.

Synthesis of fluorescein aromatic esters in the presence of P 2O5/SiO2 as catalyst and their hydrolysis studies in the presence of lipase

A series of fluorescein aryl esters were synthesized by the esterification of fluorescein with carboxylic acids in the presence of P2O 5/SiO2 and their hydrolytic properties were investigated. The rate of hydrolysis in the presence or absence of lipase, due to the increase of fluorescein concentration, was measured by monitoring of fluorescence of the solution and correlated with enzyme activity. In addition, the substitute effect on the aromatic ring of fluorescein esters was studied. In contrast to fluorescein diacetate or dibutyrate, fluorescein dibenzoate and fluorescein bis(4-methylbenzoate) were found to be better substrates for the fluorometric assay of lipase with the higher rate of hydrolysis and better Km value, respectively. As little as 9.3 ng mL-1 of lipase can be detected with fluorescein bis(4-methylbenzoate).