RESUMEN
Abstract The present research aims to determine the antimicrobial efficacy of the mouthwashes based on cetylpyridinium chloride (CPC), before aerosol producing dental procedures. A data search was performed during August 2021 in five databases MEDLINE (PubMed), SCOPUS, SCIELO, Cochrane Central Register of Controlled Trials (CENTRAL) and Google Scholar. Randomized clinical trials (RCTs) were included based on the PICO question, comparing the efficacy of the mouthwashes based on cetylpyridinium chloride (CPC), versus other mouthwashes and water, before aerosol producing dental procedures, papers in English, Spanish and Portuguese were included without time limits. The risk of the included studies was evaluated with the tool RoB 2.0. Number of registration PROSPERO N° CRD42021275982. 120 papers were obtained in the preliminary search, discarding those that didn't comply with the selection criteria, leaving only 3 studies. These papers reported the use of cetylpyridinium chloride (CPC) was effective for the reduction of bacteria during the ultrasonic prophylactic procedure. The use of CPC mouthwashes previous to the dental treatment with ultrasonic prophylaxis showed only antibacterial capacity.
Resumen El presente trabajo de investigación tiene como objetivo determinar la eficacia antimicrobiana de los colutorios a base de cloruro de Cetilpiridinio (CPC), previo a tratamientos dentales que generen aerosol. Se realizó una búsqueda bibliográfica hasta agosto del 2021 en cinco bases de datos: MEDLINE (vía PubMed), SCOPUS, SCIELO, Cochrane Central Register of Controlled Trials (CENTRAL) y Google Scholar. Se incluyeron ensayos clínicos aleatorizados (ECAs), basándose en la pregunta PICOS, que compare la eficacia del colutorio a base de cloruro de Cetilpiridinio (CPC) con otro colutorio, placebo o agua, previo a un tratamiento dental que genere aerosol, en los idiomas español, inglés o portugués y sin límite de tiempo. El riesgo de los estudios incluidos se evaluó con la herramienta RoB 2.0. Número de registro PROSPERO N° CRD42021275982. Se obtuvo un total de 120 artículos en la búsqueda preliminar, descartando aquellos que no cumplían con los criterios de selección, quedando sólo 3articulos. Estos artículos informaron que el uso de CPC es efectivo para la reducción de bacterias durante el procedimiento de profilaxis con ultrasonido. El uso de los enjuagues bucales a base de CPC previo al tratamiento dental de profilaxis con ultrasonido sólo tiene eficacia antibacteriana.
Asunto(s)
Cetilpiridinio/análisis , Antibacterianos/uso terapéutico , Antisépticos Bucales/análisisRESUMEN
A simple, ultra-sensitive, and super-stable hydrophobic SERS platform for detection of melamine in milk is developed. The hydrophobic SERS platform was constructed via directly growing hydrophobic carbon/silver nanoparticles on glass by in-situ one-step carbonization using hexadecylpyridinium chloride monohydrate as stabilizer and reducing agent. The performances of SERS platform are systematically studied by using Rhodamine 6G (R6G) as a model, which achieves detection level of 10-13 M and enhancement factor of 3.4 × 1010 for R6G detection with good uniformity and reproducibility, as well as 110 days stability in air. The FDTD simulation was used to confirm SERS enhancement mechanism. More importantly, SERS platform delivers good linear property in the range from 0.01 to 100 ppm, and low limit detection of 9 ppb for melamine detection in milk through direct drop on the platform. The SERS platform could have great applications in food safety, environmental monitoring, biomedicine and other fields.
Asunto(s)
Nanopartículas del Metal , Plata , Animales , Plata/química , Nanopartículas del Metal/química , Leche/química , Espectrometría Raman , Sustancias Reductoras/análisis , Reproducibilidad de los Resultados , Cetilpiridinio/análisis , Cloruros/análisis , Límite de Detección , Carbono/análisisRESUMEN
PURPOSE: One of the key approaches to minimize the risk of COVID-19 transmission would be to reduce the titres of SARS-CoV-2 in the saliva of infected COVID-19 patients. This is particularly important in high-risk procedures like dental treatment. The present randomized control trial evaluated the efficacy of three commercial mouth-rinse viz. povidone-iodine (PI), chlorhexidine gluconate (CHX) and cetylpyridinium chloride (CPC), in reducing the salivary SARS-CoV-2 viral load in COVID-19 patients compared with water. METHODS: A total of 36 SARS-CoV-2-positive patients were recruited, of which 16 patients were randomly assigned to four groups-PI group (n = 4), CHX group (n = 6), CPC group (n = 4) and water as control group (n = 2). Saliva samples were collected from all patients at baseline and at 5 min, 3 h and 6 h post-application of mouth-rinses/water. The samples were subjected to SARS-CoV-2 RT-PCR analysis. RESULTS: Comparison of salivary Ct values of patients within each group of PI, CHX, CPC and water at 5 min, 3 h and 6 h time points did not show any significant differences. However, when the Ct value fold change of each of the mouth-rinse group patients were compared with the fold change of water group patients at the respective time points, a significant increase was observed in the CPC group patients at 5 min and 6 h and in the PI group patients at 6 h. CONCLUSION: The effect of decreasing salivary load with CPC and PI mouth-rinsing was observed to be sustained at 6 h time point. Within the limitation of the current study, as number of the samples analyzed, the use of CPC and PI formulated that commercial mouth-rinses may be useful as a pre-procedural rinse to help reduce the transmission of COVID-19. ISRCTN (ISRCTN95933274), 09/09/20, retrospectively registered.
Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Antisépticos Bucales/uso terapéutico , SARS-CoV-2/efectos de los fármacos , Saliva/virología , Carga Viral/efectos de los fármacos , Adulto , COVID-19/prevención & control , COVID-19/transmisión , COVID-19/virología , Cetilpiridinio/análisis , Cetilpiridinio/uso terapéutico , Clorhexidina/análogos & derivados , Clorhexidina/análisis , Clorhexidina/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Antisépticos Bucales/química , Povidona Yodada/análisis , Povidona Yodada/uso terapéutico , Singapur , Resultado del Tratamiento , Adulto JovenRESUMEN
This work was concerned with development, optimization, application and validation of reversed phase high performance liquid chromatography (RP-HPLC) and thin layer chromatography (TLC)-densitometric methods for analysis of cetylpyridinium chloride, chlorocresol and lidocaine in Canyon(®) gel. The first developed RP-HPLC method depended on chromatographic separation on a ZORBAX Eclipse Plus C8 column, with elution with a mobile phase consisting of 0.05% phosphoric acid solution : acetonitrile : methanol (15 : 24 : 61, by volume), pumping the mobile phase at a flow rate of 1.00 mL min(-1), with ultraviolet detection at 220 nm. While in the subsequently developed method, the TLC-densitometric method, complete separation of the studied mixture was achieved using methanol : acetone : acetic acid (7 : 3 : 0.2, by volume) as a mobile phase, aluminum plates precoated with silica gel 60 F254 as a stationary phase and 215 nm as the scanning wavelength. Factors affecting the developed methods were studied and optimized; moreover, methods had been validated as per the International Conference of Harmonization guideline and the results indicated that the suggested methods were reproducible, reliable and applicable for rapid routine analysis. Statistical comparison of the two developed methods with the reported HPLC ones using F- and Student's t tests showed no significant difference.
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Antiinfecciosos Locales/química , Cetilpiridinio/análisis , Cresoles/análisis , Lidocaína/análisis , Acetonitrilos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Líquida de Alta Presión/normas , Cromatografía de Fase Inversa/métodos , Cromatografía de Fase Inversa/normas , Cromatografía en Capa Delgada/métodos , Cromatografía en Capa Delgada/normas , Densitometría/métodos , Densitometría/normas , Estabilidad de Medicamentos , Humanos , Metanol , Boca , Ácidos Fosfóricos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , SolventesRESUMEN
AIM: The aim of this study is to present the first total number of tested children in the Federation of Bosnia and Herzegovina and the number of children with positive sweat test. During the study we determined the number of ill children, the median age of children with cystic fibrosis, date of initial diagnosis, an average amount of chloride in the sweat. MATERIAL AND METHODS: The study was a retrospective, conducted at the Department of Pulmonology Pediatric Clinic of University Clinical Center of Sarajevo. RESULTS: In the period from March 2003 to December 2014, we have tested 625 children. 351 child were from Sarajevo Canton and 272 children from other cantons. Female children were more affected then male children, in the ratio of 1: 1,105. An average age of female children was 4.19±4.26 years, and the male 2.15±3.11 years. The median concentration of chloride in the sweat measured by sweat test was for male children 103.05±21.29 mmol/L, and for the female children 96.05±28.85 mmol/L. CONCLUSION: Most of children in Federation of Bosnia and Herzegovina have ∆F508 gene mutation. In the post-war period we started to use a sweat test. Male children tend to live longer than female children with CF.
Asunto(s)
Fibrosis Quística/epidemiología , Adolescente , Bosnia y Herzegovina/epidemiología , Cetilpiridinio/análisis , Niño , Preescolar , Fibrosis Quística/diagnóstico , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Factores Sexuales , Sudor/químicaRESUMEN
OBJECTIVE: To evaluate the efficacy of two new mouthrinses in the reduction of xerostomía-associated symptomatology. BACKGROUND: Xerostomia is a common chronic health condition that affects a great number of adults and significantly deteriorates quality of life, such that treatment is necessary. MATERIALS AND METHODS: Sixty-seven adult subjects of both sexes presenting xerostomia of diverse origin were selected. Mouthrinses were tested using a double-blind, randomized, cross-over clinical trial with an intervining wash out period. RESULTS: The 100% of subjects presented sensation of dry mouth, and 86% stated sensation of thick saliva. Burning tongue sensation, need to drink liquids to swallow and the sensation of swallowing difficulty were recorded in more than 50% of the patients. The most frequent pathologies in the sample were depression, arthritis, and arterial hypertension. Results of the clinical tests showed that mouthrinse 1 relieves sensation of dry mouth, need to drink liquids, and swallowing difficulty. In contrast, mouthrinse 2 relieves only latter two symptoms. Both rinses were more effective in relieving xerostomía-associated symptomatology in patients taking 3 or more medicines simultaneously. CONCLUSION: Both mouthrinses were effective in relieving various xerostomia symptoms, could be distributed at a low cost, thereby improving the quality of life of population affected.
Asunto(s)
Antisépticos Bucales/uso terapéutico , Xerostomía/prevención & control , Adulto , Aloe , Artritis/tratamiento farmacológico , Síndrome de Boca Ardiente/prevención & control , Cetilpiridinio/análisis , Ácido Cítrico/análisis , Estudios Cruzados , Deglución/efectos de los fármacos , Trastornos de Deglución/prevención & control , Depresión/tratamiento farmacológico , Método Doble Ciego , Femenino , Aromatizantes/análisis , Glicerol/análisis , Humanos , Hipertensión/tratamiento farmacológico , Masculino , Mentha spicata , Persona de Mediana Edad , Antisépticos Bucales/análisis , Propilenglicol/análisis , Saliva/efectos de los fármacos , Saliva/metabolismo , Tasa de Secreción/efectos de los fármacos , Cloruro de Sodio/análisis , Fluoruro de Sodio/análisis , Lengua/efectos de los fármacos , Resultado del Tratamiento , Xilitol/análisisRESUMEN
A new type of screen-printed ion-selective electrode for the determination of cetylpyridinium chloride (CPC) is presented. These new electrodes involve in situ, modified and unmodified screen-printed ion-selective electrodes for the determination of CPC. The screen-printed electrodes (SPEs) show a stable, near-Nernstian response for 1 x 10(-2) to 1 x 10(-6) M CPC at 25 degrees C over the pH range 2-8 with cationic slope 60.66+/-1.10. The lower detection limit is found to be 8 x 10(-7) M and response time of about 3s and exhibit adequate shelf-life (6 months). The fabricated electrodes can be also successfully used in the potentiometric titration of CPC with sodium tetraphenylborate (NaTPB). The analytical performances of the SPEs are compared with those for carbon paste electrode (CPE) and polyvinyl chloride (PVC) electrodes. The method is applied for pharmaceutical preparations with a percentage recovery of 99.60% and R.S.D.=0.53. The frequently used CPC of analytical and technical grade as well as different water samples has been successfully titrated and the results obtained agreed with those obtained with commercial electrode and standard two-phase titration method. The sensitivity of the proposed method is comparable with the official method and ability of field measurements.
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Cetilpiridinio/análisis , Electrodos de Iones Selectos , Potenciometría/instrumentación , Límite de Detección , Potenciometría/métodos , Volumetría/instrumentación , Volumetría/métodosRESUMEN
A new, rapid, sensitive, non-extraction batch, and flow injection spectrophotometric method for the determination of cationic surfactants (CSs) such as cetyltrimethyl ammonium bromide (CTAB), tetra-n-butyl ammonium chloride (TBAC) and cetylpyridinium chloride (CPC) is proposed. The method is based on the interaction of cationic surfactants with eriochrome black-T to form an ion-association complex. This complex has strong absorbance at 708 nm. The effects of chemical parameters and FIA variables on the determination of cationic surfactants were studied in detail, especially for CTAB. Under optimum conditions, the two linear calibration ranges of the method are 3.0 x 10(-6) to 5.0 x 10(-3)mol L(-1) CTAB, CPB and DTAB for the batch spectrophotometric method and 2.0 x 10(-6) to 2.0 x 10(-4)mol L(-1) CTAB, CPB and TBC for the flow injection spectrophotometric method. The sample throughput was 35+/-5 samples h(-1) at room temperature. The relative standard deviations for 10 replicates of analysis of (2.0, 0.6 and 0.2)x10(-4)mol L(-1) CTAB were 1.2, 1.3, and 0.8%, respectively. In addition, the influence of potential interfering substances on the determination of cationic surfactants was studied. The proposed method is simple and rapid, using no toxic organic solvents. It was applied to the determination of trace CS in industrial wastewater with satisfactory results.
Asunto(s)
Compuestos de Cetrimonio/análisis , Cetilpiridinio/análisis , Compuestos de Amonio Cuaternario/análisis , Espectrofotometría/instrumentación , Espectrofotometría/métodos , Tensoactivos/análisis , Compuestos Azo/análisis , Cetrimonio , Diseño de Equipo , Sensibilidad y Especificidad , Espectrofotometría/economía , Factores de TiempoRESUMEN
The effects of different heavy metals (Cd, Pb), surfactants (cetyltrimethylammonium bromide (CTAB), cetylpyridine chloride (CPC)) and the ionic strength (Ca2+, NH4+) on breakthrough curves (BTCs) for sorption and desorption of bisphenol A (BPA) were studied using soil column experiment. Results showed that the presence of heavy metals and cationic surfactants caused a significant increase on the BPA sorption. In addition, the volume required when effluent concentration reached half of the influent concentration (VC1/2) increased due to the introduction of heavy metals and surfactants. It was also found that the larger amount of BPA was absorbed with higher ionic strength. The cationic surfactants enhanced the desorption ability of BPA from the soil. The results provided a better understanding of BPA behavior in environment and facilitated more accurate assessment of its ecological risk and identification of appropriate management strategies.
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Fenoles/química , Contaminantes del Suelo/análisis , Adsorción , Amoníaco/química , Compuestos de Bencidrilo , Cadmio/química , Calcio/química , Cetrimonio , Compuestos de Cetrimonio/análisis , Cetilpiridinio/análisis , Iones , Plomo/química , Metales/química , Fenoles/análisis , Suelo , Contaminantes del Suelo/química , Tensoactivos/química , Temperatura , Contaminantes Químicos del Agua/químicaRESUMEN
Iron in its familiar form exists in the +2 and +3 oxidation states, however, higher oxidation state of iron +6, ferrate(VI) (Fe(VI)O(4)(2-)) can be obtained. The high oxidation power of ferrate(VI) can be utilized in developing cleaner ("greener") technology for remediation processes. This paper demonstrates the unique property of ferrate(VI) to degrade almost completely the cationic surfactant, cetylpyridinium chloride (C(5)H(5)N(+)(CH(2))(15)CH(3).H(2)O Cl(-), CPC). The Rate law for the oxidation of CPC by ferrate(VI) at pH 9.2 was found to be: -d[Fe(VI)]/dt = k[Fe(VI)][CPC](2). Ferrate(VI) oxidizes CPC within minutes and molar consumption of ferrate(VI) was nearly equal to the oxidized CPC. The decrease in total organic carbon (TOC) from CPC was more than 95%; suggesting mineralization of CPC to carbon dioxide. Ammonium ion was the other product of the oxidation. This is the first report in which Fe(VI)O(4)(2-) ion opens the pyridine ring and mineralizes the aliphatic chain of the organic molecule giving inorganic ions.
Asunto(s)
Cetilpiridinio/química , Hierro/química , Oxidantes/química , Tensoactivos/química , Purificación del Agua/métodos , Cetilpiridinio/análisis , Tensoactivos/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
The chromophore eriochrome cyanine R (ECR) was used to sensitively coordinate Al(II) and Fe(II) in the presence of cetylpyridinium chloride (CPC) at pH 4.8. Trace amounts of Fe(III) can displace Al(III) from the Al(ECR)(CPC) ternary complex to form the Fe(ECR)(CPC) complex. The composition of the complexes was determined by the break point approach. The competitive displacement complexation was sensitive and highly selective, even if no masking reagent was added. An ongoing novel spectrophotometry, named the light-absorption ratio variation approach, was applied to the direct determination of Fe(III) in natural water with recovery between 92.5 and 106%. The detection limit was only 9 ng/mL Fe(III).
Asunto(s)
Técnicas de Química Analítica/métodos , Hierro/análisis , Espectrofotometría/métodos , Agua/análisis , Bencenosulfonatos/análisis , Calibración , Cetilpiridinio/análisis , Relación Dosis-Respuesta a Droga , Concentración de Iones de Hidrógeno , Iones , Hierro/química , Factores de TiempoRESUMEN
Cetylpyridinium chloride (CPC) has been found to be effective in reducing microbial contamination in apples. A sensitive and specific HPLC method was developed to determine CPC residues in apples treated with CPC. This method involves ion exchange solid-phase extraction, and the use of stearylpyridinium chloride (SPC) as internal standard. Limit of quantitation, was 0.5 microg/ml of CPC for the apple ethanolic extracts. The observed residues in apple (2.35-4.35 microg/g of apple) were lower than those previously reported for chicken and beef. The method is specific, sensitive, reproducible and accurate.
Asunto(s)
Antiinfecciosos/análisis , Cetilpiridinio/análisis , Residuos de Medicamentos/análisis , Malus/química , Calibración , Sensibilidad y EspecificidadRESUMEN
The complexation of oligonucleotides and antisense drugs with a cationic surfactant, cetylpyridinium chloride (CPC), has been studied using electrochemistry at a micrometer sized liquid/liquid interface. This method can be used to investigate the effect of chemical and structural modifications on the complexation behaviour of oligonucleotides. For the interaction between CPC and oligonucleotides the effect of phosphorothioate derivatisation upon binding characteristics has been examined. Phosphoromonothioate modification causes the onset of binding to occur at a lower free surfactant concentration. Calorimetric studies show that surfactants are strongly bound to oligonucleotides and the binding is driven by entropy. The enthalpy change for the formation of oligonucleotide-surfactant complex is negative in all cases at 25 degrees C indicating exothermic reaction.
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Calorimetría/métodos , Cetilpiridinio/metabolismo , Oligonucleótidos/metabolismo , Cetilpiridinio/análisis , Electroquímica , Oligonucleótidos/análisisRESUMEN
Using rapid NMR velocimetry we demonstrate the existence of shear band fluctuations in the Couette flow of the wormlike micelle system, 10% w/v cetylpyridinium chloride and sodium salicylate (molar ratio 2:1) in 0.5 M 2H2O NaCl brine. We show that the fluctuations may be either quasirandom or periodic, the fluctuation spectrum being similar to that observed in the stress. Despite the equilibrium fluid being far from an isotropic-nematic transition, deuterium NMR shows that the onset of shear banding is associated with a nematic micellar state whose order parameter depends on shear rate.
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Coloides/análisis , Coloides/química , Microfluídica/métodos , Salicilato de Sodio/química , Animales , Anélidos/química , Materiales Biomiméticos/análisis , Materiales Biomiméticos/química , Cetilpiridinio/análisis , Cetilpiridinio/química , Micelas , Resistencia al Corte , Salicilato de Sodio/análisis , Estrés MecánicoRESUMEN
The HPLC method for simultaneous determination of cetylpyridinium chloride (CPC), tetracaine hydrochloride (TTC) in Xipiluan buccal tablets was developed and validated. The HPLC method was performed on a CN column (150 x 4.6 mm i.d., 5 microm particle size); the mobile phase was methanol-tetramethylammonium hydroxide (20 mM)-potassium dihydrogen phosphate (3 mM) (90:10:3, v/v/v) (pH* 5.0), pumped at a flow rate 1.5 ml min(-1). The UV detector was set at 230 nm. The retention time for CPC and TTC was 3.52 and 3.10 min, respectively. Calibration curves were linear (r=0.9999, n=6) in the range of 5-2000 microg ml(-1) for CPC and 1-500 microg ml(-1) for TTC. Limit of detection and quantitation for CPC was 0.033 and 0.11 microg ml(-1), for TTC were 0.0056 and 0.019 microg ml(-1). The R.S.D. of repeatability and intermediate precision for CPC and TTC were less than 2.0%.
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Cetilpiridinio/análisis , Comprimidos/análisis , Tetracaína/análisis , Administración Bucal , Cetilpiridinio/administración & dosificación , Cromatografía Líquida de Alta Presión/métodos , Preparaciones Farmacéuticas/análisis , Comprimidos/administración & dosificación , Tetracaína/administración & dosificaciónRESUMEN
A novel cetylpyridinium chloride-selective membrane sensor consisting of cetylpyridinium-ferric thiocyanate ion pairs dispersed in a PVC matrix placticized with dioctylphthalate is described. The electrode shows a stable, near-Nernstian response for 1 x 10(-3)-1 x 10(-6) mol l-1 cetylpyridinium chloride (CPC) at 25 degrees C over the pH range 1-6 with a cationic slope of 57.5 +/- 0.4. The lower detection limit is 8 x 10(-7) mol l-1 and the response time is 30-60 s. Selectivity coefficients for CPC relative to a number of interfering substances were investigated. There is negligible interference from many cations, anions and pharmaceutical excipients; however, cetyltrimethylammonim bromide (CTMAB) interfered significantly. The determination of 0.5-350 micrograms/ml of CPC in aqueous solutions shows an average recovery of 98.5% and a mean relative standard deviation of 1.6% at 56.0 micrograms/ml. The direct determination of CPC in Ezafluor mouthwash gave results that compare favorably with those obtained by the British Pharmacopoeia method. Precipitation titrations involving CPC as titrant are monitored with a CP sensor. The CP electrode has been utilized as an end point indicator electrode for the determination of anionic surfactants in some commercial detergents.
Asunto(s)
Cetilpiridinio/análisis , Tensoactivos/análisis , Electrodos , Concentración de Iones de Hidrógeno , Indicadores y Reactivos , Membranas Artificiales , Antisépticos Bucales/análisis , Plastificantes , Cloruro de Polivinilo , PotenciometríaRESUMEN
The aim of this work is to study the formation of chelate compound of strontium (Sr(II)) with bromopyrogallol red (BPR) and cetylpyridinium chloride (CPC) and to develop a simple, rapid and sensitive method for spectrophotometric determination of CPC in pharmaceutical products, based on the influence of micellar media on the absorption spectra of the complex of Sr(II) with BPR. The formation of the ternary complex (Sr(II)-BPR-CPC) is accompanied by a marked increase in the absorbance and a bathochromic shift in the maximal absorption of the complex from 555 to 627.5 nm, hence, there is a difference (Deltalambda=lambda(Sr) (BPR) (CPC)-lambda(Sr) (BPR)=72.5 nm) and large hyperchromic shift in lambda(max) (DeltaA=A(Sr) (BPR) (CPC)-A(Sr) (BPR)=0.258), and the ternary complex is stable for at least 2 days. The optimum pH range for the reaction is 4.0-5.0 and Beer's law is obeyed over the concentration range 0.01-0.07 mg/ml. The method has been successfully applied to the direct determination of cetylpyridinium chloride in pharmaceutical product where excellent agreement between reported and obtained results were achieved. The relative standard deviation was better than 1% in all cases.
Asunto(s)
Cetilpiridinio/análisis , Preparaciones Farmacéuticas/análisis , Espectrofotometría/métodos , Detergentes/análisisRESUMEN
A new spectrophotometric method for the simultaneous determination of benzocaine and cetylpiridinium chloride in pharmaceutical tablets, which does not require any preliminary separation or treatment of the samples, is described. The quantitative determination of both drugs was carried out using the first derivative values measured at 231.40 and 310.00 nm for benzocaine and at 220.70 nm for cetylpiridinium chloride using the zero-crossing method. The calibration graphs were linear in the ranges from 10 to 25 mg/l of benzocaine and from 4 to 20 mg/l of cetylpiridinium chloride. The developed method was successfully applied for the assay of pharmaceutical tablets and proved to be simple, sensitive and selective. Thermogravimetric techniques, Karl Fischer and loss on drying were also used for a stoichiometric evaluation of the substances studied.
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Antiinfecciosos Locales/análisis , Benzocaína/análisis , Cetilpiridinio/análisis , Calibración , Indicadores y Reactivos , Estándares de Referencia , Espectrofotometría Ultravioleta , Comprimidos , TermogravimetríaRESUMEN
The grazing incidence surface-induced dissociation (GI-SID) of n-hexadecylpyridinium and verapamil ions generated by fission fragment desorption was studied. These molecules show the effect of enhanced surface-induced dissociation at grazing incidence as it was observed in former experiments with metal organic ions. A liquid film of perfluorinated polyether is used as collision surface. Small hydrocarbon fragment ions predominate in the GI-SID spectra. Pyridine ions appear as specific fragment ions in the GI-SID spectrum of n-hexadecylpyridinium. The GI-SID conversion efficiency varies in the range 40-70%. The experimental results are discussed within the scope of a quantum mechanical model which is based on the accumulation of internal molecular energy by resonant excitation of collective vibrational states and energy transfer to a trap bond due to dipole-dipole interactions. In this context the GI-SID spectra of n-hexadecylpyridinium and verapamil ions are compared with the fragmentation occurring in regular (252)Cf plasma desorption mass spectrometry.
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Cetilpiridinio/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Verapamilo/química , Cetilpiridinio/análisis , Fluorocarburos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Espectrometría de Masa de Ion Secundario/métodos , Propiedades de Superficie , Verapamilo/análisisRESUMEN
Hyaluronan has recently been introduced as a vehicle for topical application of drugs to the skin. We sought to determine whether hyaluronan acts solely as a hydrophilic reservoir on the surface of intact skin or might partly penetrate it. Drug-free hyaluronan gels were applied to the intact skin of hairless mice and human forearm in situ, with and without [3H] hyaluronan. [3H]hyaluronan was shown by autoradiography to disseminate through all layers of intact skin in mouse and human, reaching the dermis within 30 min of application in mice. Cellular uptake of [3H]hyaluronan was observed in the deeper layers of epidermis, dermis, and in lymphatic endothelium. Absorption through skin was confirmed in mice by chromatographic analysis of blood, urine, and extracts from skin and liver, which identified 3H as intact hyaluronan and its metabolites, free acetate and water. Hyaluronan absorption was similarly demonstrated without polyethylene glycol, which is usually included in the topical formulation. [3H]hyaluronan absorption was not restricted to its smaller polymers as demonstrated by the recovery of polymers of (360-400 kDa) from both blood and skin. This finding suggests that its passage through epidermis does not rely on passive diffusion but may be facilitated by active transport. This study establishes that hyaluronan is absorbed from the surface of the skin and passes rapidly through epidermis, which may allow associated drugs to be carried in relatively high concentration at least as far as the deeper layers of the dermis.