title: Biocatalytic spectrophotometric method to detect paracetamol in water samples.
abstract: A biocatalytic methodology based on the quantification of the laccase inhibition during the oxidation of a standard substrate ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) for the indirect determination of paracetamol in drinking water has been developed. The method displayed a fast response time (20 s), and high selectivity to paracetamol in presence of interfering substances such as naproxen, estradiol, ketoprofen, sulfamethoxazole, and diclofenac. The limit of detection (LOD) and limit of quantification (LOQ) were noticed to be 0.55 µM and 8.3 µM, respectively. By comparing the catalytic constants value KM and kcat for ABTS oxidation in the absence and presence of various concentrations of paracetamol, a competitive-type inhibition was disclosed. On the other hand, the close value between Ki and KM indicates similar binding affinity of the enzyme to ABTS and paracetamol corroborated by docking studies. The methodology was successfully applied to real water samples, presenting an interesting potential for further development of a biosensor to paracetamol detection.
authors.affiliation: a Environmental Sciences Graduate Department, University of Puebla , Puebla , México.
authors.forename: Alia
authors.initials: A
authors.lastname: Méndez-Albores
authors.forename: Cristina
authors.initials: C
authors.lastname: Tarín
authors.forename: Georgette
authors.initials: G
authors.lastname: Rebollar-Pérez
authors.forename: Lenin
authors.initials: L
authors.lastname: Dominguez-Ramirez
authors.forename: Eduardo
authors.initials: E
authors.lastname: Torres
mesh_terms: D000082:Acetaminophen / Q000737:chemistry*; D018712:Analgesics, Non-Narcotic / Q000737:chemistry*; D052160:Benzothiazoles / Q000737:chemistry; D019149:Bioreactors; D002384:Catalysis; D006801:Humans; D042845:Laccase / Q000737:chemistry; D010084:Oxidation-Reduction; D013053:Spectrophotometry / Q000379:methods; D013451:Sulfonic Acids / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
chemical_list: D018712:Analgesics, Non-Narcotic; D052160:Benzothiazoles; D013451:Sulfonic Acids; D014874:Water Pollutants, Chemical; C002502:2,2'-azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid; D000082:Acetaminophen; D042845:Laccase
keywords: Emerging pollutants; laccase; paracetamol; pharmaceuticals; pollutant detection