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Biologická aktivita obsahových látek rostlin XXVIII. Alkaloidy vybraných odrůd taxonu Narcissus cyclamineus REDOUTÉ a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu. / Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesteraseJanura, Michal January 2015 (has links)
Biological activity of plant metabolites XXVIII. Alkaloids from selected cultivars of Narcissus cyclamineus REDOUTÉ and their influence on acetylcholinesterase and butyrylcholinesterase. JANURA M.: Diploma work, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2015, Czech Republic. Abstract: The summary extracts of alkaloids from bulbs of N. cyclamineus esp. N. cyclamineus cv. Jenny, N. cyclamineus cv. Little Witch, N. cyclamineus cv. Rapture, N. cyclamineus cv. Surfside, N. cyclamineus cv. Peeping Tom, N. cyclamineus cv. Warbeld and N. cyclamineus cv. Skater's Waltz were obtained by the procedures common for this type of compounds. The alkaloid extracts were analyzed by GC/MS and the probable occurrence of individual alkaloid substances was observed. These extracts were also assayed for HuAChE and HuBuChE inhibitory activity. N. cyclamineus cv. Surfside with IC50 = 61,26 ± 6,42 µg/ml and N. cyclamineus cv. Warbeld with IC50 = 85,43 ± 11,13 µg/ml have the best results in inhibition of HuBuChE. The best inhibitory activity on HuAChE has N. cyclamineus cv. Warbeld with IC50 (HuAChE) = 36,82 ± 4,50 µg/ml. Key words: Narcissus, Acetylcholinesterase, Butyrylcholinesterase, GC/MS, Alzheimer's disease.
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Studium biologické aktivity alkaloidů izolovaných z Fumaria officinalis L. (Fumariaceae) II. / Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) II.Malý, Lukáš January 2014 (has links)
Malý, L.: Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) II. Diploma Thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2014, 49 pp. Obtained diethylether extract of Fumaria officinalis L. was separated to fractions in column chromatography with petrol, chloroform and ethanol. Preparative TLC and crystalisation led to isolation of five alkaloids from fraction. Alkaloids were identified by GC-MS and NMR specters, optical rotation and melting point as protopine, cryptopine, (-)-fumaricine, (+)-fumariline and (+)-parfumidine. Isolated alkaloids were tested for their inhibition activity towards acetyl- and butyrylcholinesterase and towards prolyloligopeptidase. Activities were compared with standards. Natural inhibitor galanthamine showed IC50 AChE 1.710 ± 0.065 µM, IC50 BuChE 42.30 ± 1.30 µM. Best inhibition activity showed protopine (IC50 AChE 345.4 ± 24 µM, IC50 BuChE 239.6 ± 22.3 µM) and cryptopine (IC50 AChE 477.71 ± 47.33 µM, IC50 BuChE 270.82 ± 39.12 µM). The highest prolyloligopeptidase inhibition activity showed (+)-parfumidine with IC50 POP 99.2 µM, which was more active than used natural inhibitor baicaline (IC50 POP 605.9 ± 0.021 µM). Synthetic POP...
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Biologická aktivita obsahových látek rostlin XXIX. Alkaloidy vybraných odrůd taxonu Narcissus triandrus L. a jejich účinek na acetylcholinesterasu a butyrylcholinesterasu / Biological activity of plant metabolites XXIX. Alkaloids from selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesteraseFarkašovský, Marek January 2015 (has links)
Farkašovský M.: Biological activity of plant metabolites XXIX. Alkaloids of selected cultivars of Narcissus triandrus L. and their influence on acetylcholinesterase and butyrylcholinesterase. Diploma thesis. Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of pharmaceutical botany and ecology, Hradec Králové 2015, 70 pages Screening of seven bulb samples of Narcissus genus was performed. It included cultivars Narcissus triandrus cv. Hawera, Narcissus triandrus cv. Ice Wings, Narcissus triandrus cv. Stint, Narcissus triandrus cv. Tresamble, Narcissus cyclamineus cv. February Gold, Narcissus cyclamineus cv. Greenlet and Narcissus cyclamineus cv. Itzim. Primary extract was prepared by boiling crushed bulbs in ethanol 95% and then it was condensated. After extraction in diethyl ether and ethyl acetate was pure alkaloid extract dried with air flow in water bath. Isolated alkaloid extracts were tested for their inhibition activity on acetylcholinesterase and butyrylcholinesterase. Also GC-MS analysis was provided to identify alkaloids. These alkaloids were identified with GC-MS analysis - epinorgalanthamine, galanthamine, galanthine, haemanthamine, hippeastrine, homolycorine, cherylline, incartine, lycoramine, lycoramine-acetate, lycorine, narwedine, neruscine, sanguinine...
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Studium biologické aktivity alkaloidů izolovaných z Fumaria officinalis L. (Fumariaceae) I. / Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) I.Kostelník, Jan January 2014 (has links)
Kostelník, J.: Study of biological activity of alkaloids isolated from Fumaria officinalis L. (Fumariaceae) I. Diploma thesis, Charles University in Prague,Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2014, 63 p. The aim of this study was to isolate alkaloids from joined fraction no. 55-67 (A2) obtained from the total alkaloid fraction of extract of Fumaria officinalis L. (Fumariaceae) plant. Using chromatography methods three alkaloids were isolated and then identified by structural analysis (GC-MS, NMR). Three alkaloids were isolated by using common chromagografic methods and then identified by structural analyses optical rotation and melting point as (-)-O- methylfumarophycine, (-)-sinactine a (-)-stylopine. Inhibitory activity of isolated alkaloids was assessed against human erythrocyte acetylcholinesterase, human butyrylcholineesterase and prolyl oligopeptidase. The results were expressed as IC50 values ((-)-stylopine: IC50 AChE and IC50 BuChE > 1000 μM, IC50 POP > 1000 mM; (-)-O-methylfumarophycine: IC50 AChE = 963.10 ± 135.98 µM, IC50 BuChE = 1771.0 ± 380.94 µM, IC50 POP - unmeasured; (-)-sinactine IC50 AChE = 632.0 ± 68.12 µM, IC50 BuChE = 8154.3 ± 981.42 µM, IC50 POP = IC50 POP = 52.9 ± 1.8 µM). None of alkaloids isolated showed...
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Alkaloidy Narcissus 'Dutch 'Master' (Amaryllidaceae) a jejich biologická aktivita. II. / Alkaloids of Narcissus'Dutch Master ' (Amaryllidaceae) and their biological activity. II.Dvořáková, Zdeňka January 2016 (has links)
Dvořáková Zdeňka: Alkaloids of Narcissus 'Dutch Master' (Amaryllidaceae) and their biological activity II. Diploma thesis 2016, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology. The content of this work was isolation of compounds from the selected fraction ND-6 obtained by column chromatography of Narcissus 'Dutch Master' alkaloid extract. Preparation of extract and its column chromatography was performed by Mrg. Daniela Hulcová as part of her doctoral studies. By the means preparative TLC was from fraction ND- 6 homolycorine type alkaloid (+)-O-methyllycorenine gained. Its structure was determined on the basis NMR, GC-MS analysis and optical rotation. The obtained data were compared with facts in known literature. By the isolated alkaloid was determined its cholinesterase inhibitory activity against acetylcholinesterase and butyrylcholinesterase. Its inhibitory activity was expressed as IC50 (M) and compared with known standards galanthamine, physostigmine, and Huperzine A. This alkaloid is inactive against cholinesterase (IC50 AChE > 1000 M, IC50 BChE > 1000 M). On the basis of gained results, we can evaluate this alkaloid from the point of view of cholinesterase inhibition as potentially unusable in the treatment of AD. Key...
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Alkaloidy Narcissus 'Dutch 'Master' (Amaryllidaceae) a jejich biologická aktivita. I. / Alkaloids of Narcissus 'Dutch Master '(Amaryllidaceae) and their biological activity. I.Vacková, Lucie January 2016 (has links)
Vacková, L.: Alkaloids Narcissus 'Dutch Master' (Amaryllidaceae) and their biological activity. I. Diploma thesis, Charles University in Prague, Faculty of Pharmacy in Hradec Králové, Department of Pharmaceutical Botany and Ecology, Hradec Králové 2016. From a selected fraction ND-6, which was obtained by column chromatography of an alkaloid extract of Narcissus 'Dutch Master' (preparation of the alkaloid extract and column chromatography was performed by Mgr. Daniela Hulcová within her doctoral thesis), lycorine alakloid O-acetylpluviin was isolated using preparative TLC. Its structure was determined on the basis of MS, NMR analysis, and optical rotation, the obtained data were compared with the literature. The isolated alkaloid was tested on its possibility to inhibit human acetylcholinesterase and butyrylcholinesterase. The activity was expressed as IC 50 values (IC50 AChE = 648.03 ± 53.95 μM, IC50 BChE = 602.50 ± 48.50 μM) and compared with IC50 values of galanthamine, huperzine A and physostigmine. O-acetylpluviine showed a very low inhibitory cholinesterase activity, and so, the alkaloid does not seem to be a suitable cholinesterase inhibitor for potential use in the treatment of Alzheimer's disease. Keywords: Narcissus 'Dutch Master', Amaryllidaceae, lycorine alkaloids, Alzheimer's disease,...
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Estudo computacional da interação de terpenos com acetilcolinesterase de Rhipicephalus microplus e potenciais novos candidatos a carrapaticidas / Computational study of the interaction of terpenes with acetylcholinesterase of Rhipicephalus microplus and potential new candidates for carapaticidesLopes, Alberto Jorge Oliveira 07 July 2015 (has links)
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Previous issue date: 2015-07-07 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) / Fundação de Amparo à Pesquisa e ao Desenvolvimento Científico e Tecnológico do Maranhão (FAPEMA) / The tick Rhipicephalus microplus is the major cattle ectoparasite of the world accounting for losses of billions of dollars that directly affect the return of such livestock. Its control is difficult due to the resistance of ticks to all chemical bases commercially available miticides. Acaricidal activity of terpenes has been evaluated in several studies that show satisfactory results, indicating these compounds are potential sources of new acaricidal products. The aim of this work was to select terpenes with potential activity against enzyme acetylcholinesterase (AChE) from R. microplus. Properties of the molecular volume, geometric parameters and vibrational terpenes were obtained from quantum chemical calculations the density functional theory level. Bioinformatic methodologies were applied to study the interaction of terpenes identified in essential oils of Citrus spp. and Lippia spp. with three AChE R. microplus. Since there are no available experimental structures, models of the three AChE were generated by homology modeling and then refined by molecular dynamics simulations. Soon after, were studies of molecular docking to detect best energy conformation of interaction and molecular dynamics simulations of this complex were carried out to study the behavior of this interaction. Our results suggest that the known acaricide activity of carvacrol is associated with its interaction with AChEs, while the acaricide activity of thymol is not associated with inhibition of that enzyme. Also, as expected, showed an excellent interaction coumafos acaricide and reports the first record of interaction of AChE from R. microplus with gammamuuruleno and elemol terpenes, molecules with few studies and that now configure themselves as candidates potential new acaricidal products. / O carrapato Rhipicephalus microplus é o principal ectoparasita da bovinocultura mundial sendo responsável por perdas de bilhões de dólares que afetam diretamente o retorno de tal produção animal. Seu controle é difícil devido à resistência dos carrapatos a todas as bases químicas de acaricidas comercialmente disponíveis. A atividade acaricida de terpenos tem sido avaliada em vários estudos que mostram resultados satisfatórios, indicando que estes compostos são fontes potenciais de novos produtos acaricidas. O objetivo desse trabalho foi selecionar terpenos com potencial atividade sobre a enzima acetilcolinesterase (AChE) de R. microplus. As propriedades do volume molecular, os parâmetros geométricos e vibracionais de terpenos foram obtidos a partir de cálculos de química quântica no nível da teoria do funcional de densidade. Metodologias de bioinformática foram aplicadas para estudar a interação de terpenos identificados em óleos essenciais de Citrus spp. e Lippia spp. com as três AChE de R. microplus. Como não existem estruturas experimentais disponíveis, modelos das três AChE foram gerados por modelagem por homologia e em seguida refinadas por simulações de dinâmica molecular. Logo após, foram realizados estudos de docagem molecular para detectar a melhor conformação energética de interação e simulações de dinâmica molecular desse complexo foram realizadas para estudarmos o comportamento dessa interação. Os resultados sugerem que a conhecida atividade carrapaticida do carvacrol está associada com a sua interação com a AChE, enquanto que a atividade carrapaticida do timol não está associado com a inibição dessa mesma enzima. Além disso, como esperado, mostrou uma excelente interação do carrapaticida cumafós e relata o primeiro registro da interação da AChE de R. microplus com os terpenos gama-muuruleno e elemol, moléculas com poucos estudos e que a partir de agora configuram-se como candidatos potenciais para novos produtos acaricidas.
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Molecularly imprinted polymer sensor systems for environmental estrogenic endocrine disrupting chemicalsNtshongontshi, Nomaphelo January 2018 (has links)
Philosophiae Doctor - PhD (Chemistry) / There is growing concern on endocrine disrupting compounds (EDCs). The presence of drugs
in water supplies was first realized in Germany in the early 1990s when environmental
scientists discovered clofibric acid. Clofibric acid has the ability to lower cholesterol in ground
water below a water treatment plant. Endocrine disrupting compounds can be defined as those
chemicals with the ability to alter daily functioning of the endocrine system in living organisms.
There are numerous molecules that are regarded or referred to as EDCs such as but not limited
to organochlorinated pesticides, industrial chemicals, plastics and plasticizers, fuels, estrogens
and many other chemicals that are found in the environment or are in widespread use. 17?-
estradiol is the principal estrogen found in mammals during reproductive years. Estriol is
produced in large quantities during pregnancy. 17?-estradiol is the strongest, estriol the
weakest. Estriol is water soluble, estrone and estradiol are not. Although estrogen is produced
in women they are also at risk of over exposure to estrogen. Pesticides are extensively used
today in agricultural settings to prevent and control pests. Various pesticides, including banned
organochlorines (OCs) and modern non-persistent pesticides, have shown the ability to disrupt
thyroid activity, disturbing the homeostasis of the thyroid system. Because these EDCs have
adverse effects on health of both human and wildlife, it is imperative to develop viable costeffective
analytical methods for the detection of these EDCs in complicated samples and at
very low concentrations. Very high selectivity towards particular compounds is a very
important property for the suitability of a detection method. This is because these compounds
mostly coexist in complex matrices which makes the detection of a specific compound very
challenging. It is paramount to develop highly sensitive and selective methods for the detection
of these estrogens and phosphoric acid-based pesticides at trace levels. / 2021-08-31
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Expression des récepteurs muscariniques M2, malaises vagaux et mort subite du nourisson / Expression of muscarinic M2 receptors, vagal syncope and sudden infant death syndromeBeutelstetter, Maxime 08 March 2019 (has links)
La mort subite du nourrisson (MSN) est un phénomène imprévisible et mal compris. Elle est définie par « le décès d’un nourrisson âgé de moins d’un an dont les causes restent inexpliquées malgré des investigations approfondies, incluant une autopsie et un examen de la scène du décès ». Si l’incidence est en décroissance depuis 1994 et le début des campagnes de prévention, la MSN reste la première cause de décès post-néonatale. La MSN est un phénomène multifactoriel qui survient préférentiellement chez des enfants vulnérables exposés à des facteurs de risques environnementaux. Ainsi, le fait d’identifier ces enfants à risque est un enjeu majeur dans la prévention de cette pathologie. La réponse vagale exacerbée, exprimée biologiquement par une surexpression des récepteurs muscariniques de sous-types M2 (RM2), pourrait être un facteur de risque de MSN. Nous avons déjà constaté cette anomalie biologique dans notre modèle animal d’hyperréactivité vagale et dans des cœurs de nourrissons décédés de MSN. Le but de ces travaux est d’analyser l’expression sanguine des RM2 en tant que paramètre biologique reflétant une hyperactivité vagale chez l’Homme, dans des cas de malaises vagaux et de malaises sévères inexpliqués du nourrisson. L’implication de la génétique a également été étudiée dans une famille présentant plusieurs cas de MSN. Une surexpression des RM2 a été observée chez des patients présentant des malaises vagaux. Pour la première fois, des anomalies biologiques ont été identifiées dans cette pathologie. Si l’on parvenait à valider ce paramètre biologique en tant que marqueur de risque, cela pourrait permettre d’aider au diagnostic différentiel et à la prise en charge thérapeutique de ces syncopes vagales. Les mêmes anomalies ont été observées chez des enfants de moins d’un an présentant des malaises sévères idiopathiques. Après une première analyse des données du séquençage haut débit d’exomes issus d’une famille présentant plusieurs cas de MSN, nous avons pu identifier 3 gènes pouvant être impliqués dans la MSN. Néanmoins, le scénario et le mode de transmission sont difficiles à définir. Les premières hypothèses s’orientent vers un digénisme ou même un trigénisme. La surexpression des RM2 chez les 2 parents et chez certains enfants est un premier élément suggérant la transmission du caractère « hyperactivité vagale » chez l’Homme.Nos travaux ont permis de mettre en évidence une anomalie biologique commune entre les malaises vagaux, les malaises inexpliqués du jeune enfant et la MSN, à savoir la surexpression des RM2. Ce paramètre, facilement dosable dans le sang, pourrait être un élément complémentaire dans le diagnostic différentiel et la prise en charge de ces pathologies, notamment chez les jeunes enfants pour lesquels ces malaises peuvent être très délétères. L’avancée dans le séquençage du génome permettra peut-être l’identification de facteurs de risque génétiques impliqués dans les malaises inexpliqués ou les MSN. / Sudden Infant Death Syndrome (SIDS) is an unpredictable and poorly understood phenomenon. It is defined as the "sudden unexpected death of a child younger than one year during sleep that cannot be explained after a postmortem evaluation including autopsy, a thorough history, and scene evaluation". Although the incidence has been decreasing since 1994 and the start of prevention campaigns, SIDS remains the leading cause of post-neonatal death. SIDS is a multifactorial phenomenon that occurs preferentially in vulnerable infants exposed to environmental risk factors. Thus, identifying these children at risk is a major challenge in the prevention of this pathology. The exacerbated vagal response, biologically expressed by overexpression of muscarinic M2 receptors (M2R), may be a risk factor for SIDS. We have already observed this biological abnormality in our animal model of vagal hyperreactivity and in hearts of SIDS. The aim of this work is to analyze the blood expression of M2R as a biological parameter reflecting vagal hyperreactivity in humans, in cases of reflex syncope and idiopathic apparent life-threatening events (iALTE) of infants. The involvement of genetics has also been studied in a family with several cases of SIDS (SIDS family). Overexpression of M2R has been observed in patients with reflex syncope. For the first time, biological abnormalities have been identified in this pathology. If this biological parameter could be validated as a risk marker, it could help for differentially diagnosis and treatment of these vagal syncopes. The same abnormalities were observed in children under one year old with iALTE. After a first analysis of the data of the “next generation sequencing” of the exomes of our “SIDS family”, we were able to identify 3 genes that could be involved in SIDS. However, the scenario and the mode of transmission are difficult to define. The first hypotheses are oriented towards a digenism or even a trigenism. The overexpression of M2R in both parents is a first element suggesting the genetic transmission of the character "vagal hyperactivity" in humans. Our work highlights a biological abnormality which is common to reflex syncope, iALTE and SIDS, namely the overexpression of M2R. These results confirm the hypothesis of the involvement of the vagal system overactivity in these pathologies. This parameter, easily measurable in the blood, could be a complementary assessment useful in the differential diagnosis and the management of these pathologies, in particular in infants for whom syncope can be very harmful. The development of the sequencing of human genome will probably allow the identification of genetic risk factors involved in iALTE or SIDS.
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Mise en oeuvre de biocapteurs en vue de la détection de pesticides dans l'eau par diffusion Raman exaltée / Implementation of biosensors for the detection of pesticides and pollutants in water by exalted Raman scatteringEl Alami, Amal 20 April 2017 (has links)
La diffusion Raman exaltée de surface (SERS) est utilisée pour la mise au point d’un biocapteur capable de détecter des pesticides dans l’eau, en se basant sur le suivi de l’activité enzymatique de l’Acétylcholinestérase (ACHE). Les nanoparticules d’or sont utilisées comme substrats SERS actifs. Le signal Raman exalté de l’analyte est optimisé en testant plusieurs types de nanoparticules.Le Raman SERS a permis la détection directe du Paraoxon (PO) et du carbaryl (CA) et la possibilité de suivi de l’activité de l’ACHE. En absence d'inhibiteurs, la molécule d’acétylcholine (ATC) est transformée en acide acétique et en choline par l’enzyme ACHE. La mesure de l’activité de l’ACHE repose sur le suivi des concentrations en ATC car sa transformation est inhibée en présence de pesticides. Il a été ainsi possible d’établir une relation linéaire entre la concentration de pesticides et l’exaltation du signal Raman de l’ATC non transformé. La méthode a permis la détection du PO et du CA, avec une limite de détection beaucoup plus faible que la détection directe. Ce biocapteur basé sur l’activité de l’ACHE a ensuite été utilisé pour l'évaluation d’autres polluants (inhibiteurs d’ACHE) comme les additifs contenus dans les plastiques notamment. Enfin, nous avons développé une seconde approche qui consistait à mesurer l’activité de l’ACHE en utilisant la diffusion dynamique de la lumière. En effet, nous avons montré que les paramètres physicochimiques (agrégation) des AuNPs en contact avec certaines molécules, sont fortement influencés par l’activité enzymatique de l’ACHE. C’est ce phénomène d’instabilité qui nous a permis de distinguer entre les deux cas : absence et présence de PO. / Surface-enhanced Raman scattering (SERS) was used to develop a biosensor for the detection of pesticides through the monitoring of the enzymatic activity of acetylcholinesterase (ACHE). Gold nanoparticles (AuNPs) were used as an active SERS substrate. The enhanced Raman signal of the analyte is optimized by testing several types of nanoparticles. Raman SERS allowed the direct detection of Paraoxon (PO) and carbaryl (CA) pesticides and the possibility of follow-up of the activity of the ACHE. In the absence of inhibitors, the acetylcholine (ATC) is transformed into acetic acid and choline by the enzyme ACHE. The measurement of ACHE activity is performed through the monitoring of ATC concentrations because its transformation is inhibited in the presence of pesticides. Results showed a linear correlation between the concentration of pesticides and the SERS signal of the untransformed ATC. The method was optimized for the quantification of paraoxon and carbaryl with a limit of quantification much lower than the one obtained with a direct detection. Their identification was also possible using chemometrics. This biosensors, based on the ACHE activities, was applied to the evaluation of emergent pollutants: additives of commercial polymers. Our results suggested that most of the tested polymers contained molecules that act as inhibitors of the ACHE. Finally, we propose another very simple approach to measure the ACHE activity using dynamic light scattering measurements. We found that the physicochemical parameters (aggregation) of AuNPs were strongly influenced by the enzymatic activity of ACHE when in contact with specified molecules, allowing to detect the presence of PO.
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