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1.
J Environ Radioact ; 216: 106185, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32217198

RESUMO

The Modane underground laboratory (LSM) is the deepest operating underground laboratory in Europe. It is located under the Fréjus peak in Savoie Alps in France, with average overburden of 4800 m w. e. (water equivalent), providing low-background environment for experiments in nuclear and particle physics, astrophysics and environmental physics. It is crucial to understand individual sources of background such as residual cosmic-ray flux of high-energy muons, muon-induced neutrons and contributions from radionuclides present in the environment. The identified dominant sources of background are radioactive contamination of construction materials of detectors and laboratory walls, radon contamination of the laboratory air, and neutrons produced in the laboratory. The largest neutron contribution has been identified from (α, n) reactions in low Z materials (10-7-10-4 n s-1 Bq-1) and from spontaneous fission of 238U (1.1× 10-6 n s-1 Bq-1).


Assuntos
Monitoramento de Radiação , Europa (Continente) , Fenolftaleína , Radioisótopos
2.
An Acad Bras Cienc ; 91(4): e20180734, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31644643

RESUMO

Seed companies are looking for promising, quick and effective alternatives to determine the physiological quality of seeds. The objective of the current work was to study the efficiency of the exudate - phenolphthalein pH test to evaluate the seeds of two lots of Libidibia ferrea (Mart. ex Tul.) L. P. Queiroz var. ferrea. The statistical design for the the exudate - phenolphthalein pH test was completely randomized with four replicates of 50 seeds in a factorial design (2 x 5), two seed lots and five soaking periods (30, 60, 90, 120, and 150 minutes), respectively, using two constant temperatures (25 and 30°C). The percentage of viability and germination of the seeds did not differ in the temperatures of 25 and 30°C and in the soaking periods by the exudate - phenolphthalein pH test. Thus, it is recommended that the test be conducted for at least 30 minutes in distilled and deionized water at the constant temperature of 25 or 30°C to evaluate the vigor of the Libidibia ferrea.


Assuntos
Caesalpinia/crescimento & desenvolvimento , Germinação/fisiologia , Fenolftaleína/análise , Sementes/crescimento & desenvolvimento , Caesalpinia/fisiologia , Concentração de Íons de Hidrogênio , Controle de Qualidade , Sementes/fisiologia , Temperatura
3.
Mikrochim Acta ; 186(9): 611, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31396712

RESUMO

A colorimetric test is described for the rapid detection of Staphylococcus aureus (SA). Gold nanorods (AuNRs) are first labeled with urease and yolk immunoglobulin (IgY). This probe can specifically bind SA. In the next step, nonspecific magnetic beads and sample are added. This leads to the formation of the AuNR-IgY-SA-nMB immunocomplex which is then magnetically separated. Finally, a solution of urea is added to the supernatant. Ureases catalyzes the decomposition of urea which results in an increase in the pH value. The increase in the pH value is detected by using a phenolphthalein test paper which undergoes a color change from white to pink. The analytical process can be completed within 20 min. The method is highly specific and can detect as little as 476 cfu·mL-1. It was verified by analyzing contaminated Chinese cabbage and beef samples, and 1000 cfu·mL-1 of SA were accurately detected. Graphical abstract Schematic representation of a colorimetric method for the detection of Staphylococcus aureus based on the immunocomplex formed from dual-labeled gold nanorod (AuNR) probe, bacteria and non-specific magnetic bead (nMB). This method can be completed within 20 min.


Assuntos
Técnicas Biossensoriais/métodos , Ouro/química , Imunoglobulinas/química , Imãs/química , Fenolftaleína/química , Staphylococcus aureus/isolamento & purificação , Urease/química , Colorimetria , Gema de Ovo/química , Microesferas , Nanotubos/química , Papel
4.
J Forensic Sci ; 64(3): 878-887, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30380138

RESUMO

Accurate blood detection is a primary concern for forensic scientists, especially in highly compromised situations. In this study, blood was added to wood blocks and subjected to a variety of fire treatments: the absence or presence of accelerant, burn time (1, 3, or 5 min), and extinguishment method (smothering or dousing with water). Burned blocks were given a qualitative burn score, followed by removal of half of the char from each block and subsequent testing of each half for blood using luminol (13% positive; n = 96), Bluestar® Forensic Magnum (5.2% positive; n = 96), and combined phenolphthalein tetramethylbenzidine test (0% positive; n = 192). Luminol and Bluestar® Forensic Magnum performed similarly, both outperforming PTMB. Additionally, positive results were more likely from samples that were smothered, had a low burn score, and had more concentrated blood solutions (neat or 1:2). Overall, it is extremely unlikely that blood would be detected on combustible substrates exposed to direct fire.


Assuntos
Manchas de Sangue , Fogo , Medicina Legal/métodos , Substâncias Luminescentes , Madeira , Benzidinas , Humanos , Indicadores e Reagentes , Luminol , Fenolftaleína , Fatores de Tempo
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 208: 131-139, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30308397

RESUMO

A novel fluorescent probe, phenolphthalein­dialdehyde­(2­pyridyl) hydrazone (L), for sequentially detecting Al3+ and F- in almost 100% aqueous medium was successfully designed and synthesized. The probe offers two binding pockets for Al3+ to form a 1: 2 ligand/metal complex, leading to a significant fluorescence enhancement at 465 nm. Further, the in-situ formed L-Al complex acts as a secondary fluorescent chemosensor for F- by quenching the fluorescence of the complex with high selectivity. The detection limit for Al3+ and F- sensing is 2.28 nM and 0.13 µM, respectively, which are far below the World Health Organization (WHO) acceptable limits (7.41 µM for Al3+ ion and 79 µM for F-) in drinking water. The probe L was successfully applied to the detection of Al3+ and F- in cells using fluorescence microscopy.


Assuntos
Alumínio/análise , Corantes Fluorescentes/química , Fluoretos/análise , Fenolftaleína/química , Água/química , Ânions , Linhagem Celular Tumoral , Sobrevivência Celular , Corantes Fluorescentes/síntese química , Humanos , Concentração de Íons de Hidrogênio , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Pediatr Emerg Care ; 35(7): e127, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29746360

RESUMO

A 5-year-old female with Charcot-Marie-Tooth neuropathy and a history of constipation presented to the emergency department with a new blistering buttocks rash, which was initially concerning for nonaccidental burn. Upon further investigation, it was found that Ex-Lax had been given to the patient for constipation. This had resulted in a bowel movement, which led to an irritant dermatitis. The patient was eventually diagnosed with senna-induced erosive diaper dermatitis. This case report highlights the importance of a thorough history and physical examination to prevent an unnecessary child abuse work-up.


Assuntos
Dermatite de Contato/etiologia , Dermatite das Fraldas/diagnóstico , Laxantes/efeitos adversos , Fenolftaleína/efeitos adversos , Doença de Charcot-Marie-Tooth/complicações , Maus-Tratos Infantis/diagnóstico , Pré-Escolar , Constipação Intestinal/tratamento farmacológico , Diagnóstico Diferencial , Dermatite das Fraldas/etiologia , Feminino , Humanos
7.
Luminescence ; 34(1): 106-112, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30565395

RESUMO

A reversible and easy assembled fluorescent sensor based on calix[4]arene and phenolphthalein (C4P) was developed for selective zinc ion (Zn2+ ) sensing in aqueous samples. The probe C4P demonstrated high selective and sensitive detection towards Zn2+ over other competitive metal ions. Interaction of Zn2+ with a solution of C4P resulted in a considerable increment in emission intensity at 440 nm (λex  = 365 nm) due to the suppression of photoinduced electron transfer (PET) process and the restriction of C=N isomerization. The binding constant (Ka ) of C4P with Zn2+ was calculated to be 4.50 × 1011  M-2 and also the limit of detection of C4P for Zn2+ was as low as 0.108 µM (at 10-7  M level). Moreover, the fluorescence imaging in the human colon cancer cells suggested that C4P had great potential to be used to examine Zn2+ in vivo.


Assuntos
Calixarenos/química , Corantes Fluorescentes/química , Imagem Molecular/métodos , Fenolftaleína/química , Fenóis/química , Zinco/análise , Cádmio/química , Linhagem Celular Tumoral , Cisteína/química , Humanos , Isomerismo , Limite de Detecção , Espectroscopia de Ressonância Magnética , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta
9.
J Forensic Sci ; 63(1): 234-238, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28271501

RESUMO

Distribution of homogeneous fingermarks in blood is essential for conducting proficiency tests in forensic science. Hence, the artificial blood was prepared using the root nodule extract of Glycine max plants. The reactivity of the artificial blood with widely used human blood detection reagents was tested. Artificial latent fingermarks in blood were printed using an inkjet cartridge case filled with artificial blood solution. The artificial latent fingermarks in blood were developed with amino acid-sensitive reagents and could obtain development as prominent as the image of the master fingermark saved on the computer. Therefore, it has been confirmed that the extract of legume root nodules can be used as artificial blood, and the artificial blood can be used for the preparation of artificial latent fingermarks or footmarks in blood.


Assuntos
Substitutos Sanguíneos , Dermatoglifia , Fabaceae/química , Extratos Vegetais/química , Raízes de Plantas/química , Compostos Aza , Corantes , Ciências Forenses , Humanos , Indanos , Indicadores e Reagentes , Leghemoglobina , Ninidrina , Fenolftaleína
10.
Chemphyschem ; 18(13): 1752-1754, 2017 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-28185359

RESUMO

A phenolphthalein-based colorimetric probe bearing a dinitrobenzene group is reported as a thiophenol (PhSH)-selective chemodosimeter. PhSH can react with chemodosimeter 1 to afford phenolphthalein. The addition of PhSH to the aqueous solution of 1 followed by a change in pH of the resulting solution to basic induces a selective color change from colorless to pink. Furthermore, using PhSH and base as inputs and color change of 1 by naked eye as an output, leads to the construction of an AND logic gate.


Assuntos
Colorimetria/métodos , Fenolftaleína/química , Fenóis/análise , Compostos de Sulfidrila/análise , Concentração de Íons de Hidrogênio , Estrutura Molecular , Fenolftaleína/análise , Fenolftaleína/síntese química , Fenóis/química , Compostos de Sulfidrila/química
11.
Food Chem ; 224: 329-334, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28159275

RESUMO

Slimming supplements were popularly sold online driven by the increasement of obesity and the development of social networking platform. However, events of drug abuse in slimming supplements were also frequently reported. In this study, a graphene tip solid-phase extraction (Gtip SPE) and ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method was established for determining fenfluramine, phenolphthalein, bumetanide, and sibutramine in slimming supplements. It was validated in terms of linearity (0.9985-0.9995), LOD (1.8ngmL-1), LOQ (5.6ngmL-1), intra-day precision (<5.1%), inter-day precision (<7.3%), and recovery (82.9-95.2%). Sibutramine is the most commonly used drug, which was detected in Bihais, Galong, and Aolist, with content 12.4, 3.6, 20.3mgg-1, respectively. Phenolphthalein was also found with content lower than 5.2mgg-1. The successful application of Gtip SPE and UPLC-MS/MS method indicated its advantage in analyzing low level of contaminates resulted from violation of regulation.


Assuntos
Depressores do Apetite/análise , Cromatografia Líquida , Suplementos Nutricionais/análise , Grafite/química , Espectrometria de Massas em Tandem , Bumetanida/análise , Ciclobutanos/análise , Fenfluramina/análise , Limite de Detecção , Fenolftaleína/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase Sólida
12.
Cochrane Database Syst Rev ; 1: CD011128, 2017 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-28116777

RESUMO

BACKGROUND: Antipsychotic-related constipation is a common and serious adverse effect, especially for people taking clozapine. Clozapine has been shown to impede gastrointestinal motility, leading to constipation, and has been reported in up to 60% of patients receiving clozapine. In rare cases, complications can be fatal. Appropriate laxatives should be prescribed to treat constipation in people taking antipsychotics, but there is a lack of guidance on the comparative effectiveness and harms of different agents in this population. An understanding of the effectiveness and safety of treatment for antipsychotic-related constipation is important for clinicians and patients alike. OBJECTIVES: To evaluate the effectiveness and safety of pharmacologic treatment (versus placebo or compared against another treatment) for antipsychotic-related constipation (defined as constipated patients of any age, who are treated with antipsychotics, regardless of dose, in which constipation is considered to be an antipsychotic-related side effect). SEARCH METHODS: We searched the Cochrane Schizophrenia Group's Trials Register (15 June 2015), which is based on regular searches of MEDLINE, Embase, CINAHL, BIOSIS, AMED, PubMed, PsycINFO, and registries of clinical trials, grey literature, and conference proceedings. There are no language, date, document type, or publication status limitations for inclusion of records in this register. We also handsearched bibliographies and contacted relevant authors for additional information. SELECTION CRITERIA: We included all published and unpublished randomised controlled trials (RCTs) investigating the efficacy of pharmacological treatments in patients with antipsychotic-related constipation. Pharmacological treatments included laxatives and other medicines that could reasonably be used to combat constipation in this population (e.g. anticholinergic agents, like bethanecol). DATA COLLECTION AND ANALYSIS: Two review authors independently extracted data from all included studies and assessed trials for risk of bias. A third author reviewed 20% of trials. We analysed dichotomous data using relative risks (RR) and the 95% confidence intervals (CI). We assessed risk of bias for included studies and used GRADE to create a 'Summary of findings' table. We discussed any disagreement, documented decisions, and attempted to contact study authors when necessary. MAIN RESULTS: We identified two relevant Chinese studies (N = 480) that contributed data to this review. Both studies were over ten years old and poorly reported, lacking descriptions of contemporary CONSORT reporting prerequisites, such as sequence generation, allocation concealment, blinding, participant flow, how the sample size was determined, or how outcomes were measured. The studies also did not report trial registration, pre-specified protocols, consent processes, ethical review, or funding source. We were unsuccessful in making contact with the authors to clarify the missing details. We classified both studies as having an overall high risk of bias.One study compared glycerol suppository with the traditional Chinese medicine (TCM) approaches of tuina massage and acupuncture. Compared to tuina massage, glycerol laxative was less effective in relieving constipation at both two days after treatment (1 RCT; N = 120; RR 2.88, 95% CI 1.89 to 4.39; very low-quality evidence), and three days (1 RCT; N = 120; RR 4.80, CI 1.96 to 11.74, very low-quality evidence). Favourable results were also seen for acupuncture at two days (1 RCT; N = 120; RR 3.50; 95% CI 2.18 to 5.62; very low-quality evidence), and at three days (1 RCT; N = 120; RR 8.00, 95% CI 2.54 to 25.16; very low-quality evidence).The other study compared mannitol, an osmotic laxative, with rhubarb soda or phenolphthalein. Mannitol was more effective than rhubarb soda or phenolphthalein in trelieving constipation within 24 hours of treatment (1 RCT; N = 240; RR 0.07; 95% CI 0.02 to 0.27, very low-quality evidence).No data were reported for our other important outcomes: need for rescue medication, bowel obstruction (a complication of antipsychotic-related constipation), quality of life, adverse events, leaving the study early, and economic costs. AUTHORS' CONCLUSIONS: We had hoped to find clinically useful evidence appraising the relative merits of the interventions routinely used to manage antipsychotic-related constipation, a common and potentially serious adverse effect of the use of these drugs. The results were disappointing. There were no data comparing the common pharmacological interventions for constipation, such as lactulose, polyethylene glycol, stool softeners, lubricant laxatives, or of novel treatments such as linaclotide. Data available were very poor quality and the trials had a high risk of bias. Data from these biased studies suggested that mannitol, an osmotic laxative, was more effective than rhubarb soda and phenolphthalein in relieving constipation, and a two-week course of glycerol suppositories was less effective than the TCM approaches of tuina massage and acupuncture.Overall, there is insufficient trial-based evidence to assess the effectiveness and safety of pharmacological interventions for treating antipsychotic-related constipation, due to limited, poor quality data (few studies with high risk of bias and no meta-analyses). The methodological limitations in the included studies were obvious, and any conclusions based on their results should be made with caution. Methodologically rigorous RCTs evaluating interventions for treating antipsychotic-related constipation are needed.


Assuntos
Antipsicóticos/efeitos adversos , Constipação Intestinal/tratamento farmacológico , Glicerol/uso terapêutico , Laxantes/uso terapêutico , Manitol/uso terapêutico , Fenolftaleína/uso terapêutico , Rheum , Terapia por Acupuntura , Constipação Intestinal/induzido quimicamente , Humanos , Massagem/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Supositórios
13.
Mater Sci Eng C Mater Biol Appl ; 69: 1018-25, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27612798

RESUMO

Current investigations deal with new surface functionalization strategy of nanocrystalline cellulose-based substrates to impart active molecule release properties. In this study, cellulose nanocrystals (CNC) were surface-functionalized with ß-cyclodextrin (ß-CD) using succinic acid (SA) and fumaric acid (FA) as bridging agents. The main objective of this surface modification performed only in aqueous media was to obtain new active materials able to release antibacterial molecules over a prolonged period of time. The reactions were conducted by immersing the CNC film into a solution composed of ß-CD, SA and FA, leading to CNC grafting. The materials were characterized by infrared spectroscopy (FT-IR), Quartz crystal microbalance-dissipation (QCM-D), AFM and phenolphthalein (PhP) was used to determine the efficiency of CNC grafting with ß-CD. The results indicated that ß-CD was successfully attached to the CNC backbone through the formation of ester bonds. Furthermore, carvacrol was entrapped by the attached ß-CD and a prolonged release was confirmed. In particular, CNC grafted to ß-CD in the presence of FA was selected as the best solution. The antibacterial activity and the controlled release were studied for this sample. Considerably longer bacterial activity against B. subtilis was observed for CNC grafted to ß-CD compared to CNC and CNC-FA, confirming the promising impact of the present strategy.


Assuntos
Ácidos Carboxílicos/química , Celulose/química , Monoterpenos/farmacologia , Nanopartículas/química , beta-Ciclodextrinas/química , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Cimenos , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Microscopia de Força Atômica , Peso Molecular , Fenolftaleína/química , Técnicas de Microbalança de Cristal de Quartzo , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
14.
J AOAC Int ; 99(4): 929-940, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27143234

RESUMO

The purpose of this study was to develop an LC-tandem MS method for the simultaneous detection of common synthetic drugs as adulterants in natural and herbal slimming products. Sixteen drugs belonging to a wide range of pharmaceutical classes were studied. Included in the list of drugs were anorexics, anxiolytics, antidepressants, diuretics, laxatives, and stimulants. The method used a C18 column (4.6 × 50 mm and 1.8 µm particle size). Separation of the drugs was achieved by gradient elution using 4 mM ammonium formate in water + 0.1% formic acid as the aqueous component and 4 mM ammonium formate in methanol + 0.1% formic as the organic component of the mobile phase. As not all of the analytes ionized in the positive mode, the mass spectrometer was operated in the electrospray ionization mode with polarity switching. The samples were extracted with methanol and the use of 50% acetonitrile in water and 50% methanol in water were investigated as diluents for injection into the LC-MS system. Utilizing both diluents, the validation parameters including accuracy, precision, LOD, and LOQ were assessed. The validation results and utilization of the method to analyze a variety of weight-loss supplements indicate that the two diluents give similar results and can be used interchangeably. This knowledge provides the user with the option of selecting either diluent for sample preparation depending on the sample matrix without having to revalidate the method. The method was applied to the analysis of weight-loss supplements available in local pharmacies, herbal pharmacies, and over the Internet.


Assuntos
Fármacos Antiobesidade/análise , Contaminação de Medicamentos , Preparações de Plantas/análise , Cafeína/análise , Cromatografia Líquida , Ciclobutanos/análise , Fenolftaleína/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
15.
Forensic Sci Int ; 262: 156-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26990564

RESUMO

There are numerous presumptive tests available in the forensic science field to help identify the presence of blood. While many articles are available on the effects of Bluestar(®) and luminol and potential interactions with subsequent DNA identification, the research field falls short in identifying the effects these two presumptive tests may have on subsequent presumptive tests used to help identify blood. To rectify this ongoing issue in the forensic science field, the chemiluminescence methods of Bluestar(®) and luminol for the detection of blood at a crime scene were tested for their effects when used in conjunction with tetramethylbenzidine (TMB) or phenolphthalein (PT) at the forensic science laboratory. Six different substrates (untreated wood, pressure treated wood, ceramic tile, shag carpet, cement block, and cotton clothing) were stained with varying dilutions (range 1:1 to 1:100,000) of blood. Neither luminol nor Bluestar(®) affect the results of PT or TMB tests at blood dilutions equal to or less than 1:100. However, interactions did occur between agents and substrates with blood dilutions 1:1000 or greater. Bluestar(®) was the only presumptive test that can detect blood dilutions of 1:100,000 on some substrates and luminol was inclusive on pressure treated wood. These findings suggests that forensic science laboratory personal need to know and understand the details of how the blood was detected by the crime scene investigator and the substrate on which the blood was obtained from for their preparation of presumptive blood testing with PT or TMB.


Assuntos
Benzidinas , Manchas de Sangue , Substâncias Luminescentes , Luminol , Fenolftaleína , Medicina Legal , Humanos , Indicadores e Reagentes , Propriedades de Superfície
16.
Carbohydr Polym ; 136: 329-40, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26572363

RESUMO

Cellulose was cross-linked with epichlorohydrin (EP) at variable levels (CLE-0.5, CLE-2 and CLE-4), where CLE-i denotes the cellulose to EP mole ratios. The cross-linked products were characterized by TGA and FT-IR spectroscopy, pH at the point of zero charge (pHpzc), water swelling, and dye-adsorption methods employing two types of dyes [phenolphthalein (phth) and p-nitrophenol (PNP)]. The characterization methods provide evidence of cross-linking of cellulose in accordance with variations in surface area, PZC, available surface hydroxyl groups, and thermal stability when compared against pristine cellulose. The pHpzc of the sorbent materials was ∼ 6.5 indicating a negative surface charge occurs above pHpzc. The cross-linked polymers possess greater swelling properties relative to pristine cellulose. Detailed adsorption studies were carried out at pH 9 for cellulose and CLE-i with five types single component carboxylate anions [2-hexyldecanoic acid (S1), trans-4-pentylcyclohexanecarboxylic acid (S2), 2-dicyclohexylacetic acid (S3), adamantane carboxylic acid (S4), and cyclohexane carboxylic acid (S5)] at 295 K. The uptake properties of PNP with cellulose and CLE-i were also compared at pH 5 and 9, respectively. CLE-2 had the highest uptake of PNP (Qm=1.22 × 10(-1)mmol/g, pH 9) and S1 (Qm=4.27 mg/g) while cellulose and CLE-4 had the strongest binding affinity (1.43 L/mmol and 5.90 × 10(-2)L/mg), respectively. Uptake of PNP by CLE-0.5 at pH 5 (Q m=5.30 × 10(-2)mmol/g) was higher than uptake at pH 9 (Qm=3.11 × 10(-2)mmol/g). Sorption of CLE-4 with S1, S2 and S3 showed that relative uptake of the surrogates had the following order: S3>S2>S1, where S2 had the strongest binding affinity to CLE-i. CLE-2 had the highest sorption capacity towards Si in an equimolar mixture with evidence of molecular selective uptake. At pH 9, low uptake was mainly related to electrostatic repulsion between the negatively charged sorbent surface and the carboxylate head groups of Si.


Assuntos
Celulose/química , Epicloroidrina/química , Polímeros/química , Água/química , Adsorção , Cor , Modelos Moleculares , Conformação Molecular , Fenolftaleína/química , Soluções , Propriedades de Superfície
18.
Talanta ; 138: 77-85, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25863375

RESUMO

To counter the growth of herbal medicines adulterated with pharmaceuticals crossing borders, rapid, inexpensive and non-destructive analytical techniques, that can handle complex matrices, are required. Since mid-infrared (MIR), near infrared (NIR) and Raman spectroscopic techniques meet these criteria, their performance in identifying adulterants in seized weightloss herbal medicines is definitively determined. Initially a validated high pressure liquid chromatography methodology was used for reference identification and quantification of the adulterants sibutramine H2O·HCl, fenfluramine HCl and phenolphthalein. Of 38 products, only sibutramine and phenolphthalein were detected by HPLC. The spectroscopic measurements showed Raman was ill-suited due to sample burning and emission while NIR lacked adulterant selectivity. Conversely, MIR demonstrated apt identification performance, which manifested as spectrally meaningful separation based on the presence and type of adulterant during principal component analysis (test set validated). Partial least squares regression models were constructed from the MIR training sets for sibutramine and phenolphthalein - both models fitted the training set data well. Average test set prediction errors were 0.8% for sibutramine and 2.2% for phenolphthalein over the respective concentration ranges of 1.7-11.7% and 0.9-34.4%. MIR is apposite for the screening of anorectic and laxative adulterants and is the most viable technique for wider adulterant screening in herbal medicines.


Assuntos
Suplementos Nutricionais/análise , Contaminação de Medicamentos , Medicina Herbária , Plantas Medicinais/química , Espectrofotometria Infravermelho/métodos , Análise Espectral Raman/métodos , Ciclobutanos/análise , Humanos , Fenolftaleína/análise , Análise de Componente Principal , Vibração
19.
J Nucl Med ; 56(3): 483-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25655631

RESUMO

UNLABELLED: We report the design, testing, and in vivo application of pH-sensitive contrast agents designed specifically for Cerenkov imaging. Radioisotopes used for PET emit photons via Cerenkov radiation. The multispectral emission of Cerenkov radiation allows for selective bandwidth quenching, in which a band of photons is quenched by absorption by a functional dye. Under acidic conditions, (18)F-labeled derivatives emit the full spectrum of Cerenkov light. Under basic conditions, the dyes change color and a wavelength-dependent quenching of Cerenkov emission is observed. METHODS: Mono- and di-(18)F-labeled derivatives of phenolsulfonphthalein (phenol red) and meta-cresolsulfonphthalein (cresol purple) were synthesized by electrophilic fluorination. Cerenkov emission was measured at different wavelengths as a function of pH in vitro. Intramolecular response was measured in fluorinated probes and intermolecular quenching by mixing phenolphthalein with (18)F-FDG. Monofluorocresol purple (MFCP) was tested in mice treated with acetazolamide to cause urinary alkalinization, and Cerenkov images were compared with PET images. RESULTS: Fluorinated pH indicators were produced with radiochemical yields of 4%-11% at greater than 90% purity. Selective Cerenkov quenching was observed intramolecularly with difluorophenol red or monofluorocresol purple and intermolecularly in phenolphthalein (18)F-FDG mixtures. The probes were selectively quenched in the bandwidth closest to the indicator's absorption maximum (λmax) at pHs above the indicator pKa (the negative logarithm of the acid dissociation constant). Addition of acid or base to the probes resulted in reversible switching from unquenched to quenched emission. In vivo, the bladders of acetazolamide-treated mice exhibited a wavelength-dependent quenching in Cerenkov emission, with the greatest reduction occurring near the λmax. Ratiometric imaging at 2 wavelengths showed significant decreases in Cerenkov emission at basic pH and allowed the estimation of absolute pH in vivo. CONCLUSION: We have created contrast agents that selectively quench photons emitted during Cerenkov radiation within a given bandwidth. In the presence of a functional dye, such as a pH indicator, this selective quenching allows for a functional determination of pH in vitro and in vivo. This method can be used to obtain functional information from radiolabeled probes using multimodal imaging. This approach allows for the imaging of nonfluorescent chromophores and is generalizable to any functional dye that absorbs at suitable wavelengths.


Assuntos
Meios de Contraste/química , Radioisótopos de Flúor/química , Fenolsulfonaftaleína/análogos & derivados , Radioisótopos/química , Acetazolamida/química , Animais , Modelos Animais de Doenças , Fluordesoxiglucose F18 , Concentração de Íons de Hidrogênio , Camundongos , Modelos Químicos , Imagem Multimodal , Óptica e Fotônica , Fenolftaleína/química , Fenolsulfonaftaleína/química , Fótons , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos
20.
Artigo em Inglês | MEDLINE | ID: mdl-25247833

RESUMO

Herbal food supplements claiming to reduce weight may contain active pharmacological ingredients (APIs) that can be used for the treatment of overweight and obesity. The aim of this study was to determine whether herbal food supplements for weight loss on the Dutch market contain APIs with weight loss properties. Herbal food supplements intended for weight loss (n = 50) were sampled from August 2004 to May 2013. An HPLC-DAD-MS/MS method was used to screen for the presence of the APIs in herbal supplements. In 24 samples the APIs sibutramine, desmethylsibutramine (DMS), didesmethylsibutramine (DDMS), rimonabant, sildenafil and/or the laxative phenolphthalein were identified 41 times. The presence of these APIs was, however, not stated on the label. The potential pharmacological effects of the detected APIs were estimated using data from reported effective doses of approved drugs. Use of 20 of the 24 herbal food supplements may result in potential pharmacological effects. Furthermore, risk assessment of phenolphthalein, a suspected carcinogen and found to be present in 10 supplements, based on the margin of exposure (MOE) approach, resulted in MOE values of 96-30,000. MOE values lower than 10,000 (96-220) were calculated for the daily intake levels of four out of these 10 supplements in which phenolphthalein was found. However, taking into account that weight loss preparations may be used for only a few weeks or months rather than during a lifetime, MOE values may be two to three orders of magnitude higher. The current study shows that the use of food supplements with sibutramine, DMS, DDMS and/or phenolphthalein could result in pharmacological effects.


Assuntos
Fármacos Antiobesidade/análise , Suplementos Nutricionais/análise , Obesidade/dietoterapia , Perda de Peso , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Humanos , Países Baixos , Fenolftaleína/análise , Fenolftaleína/toxicidade , Medição de Risco , Espectrometria de Massas em Tandem
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