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The study proposes a simple and efficient way to synthesize a heterogeneous catalyst that can be used for the degradation of organic dyes. A simple and fast chemical process was employed to synthesize Au: Ni: Co tri-metal nanohybrid structures, which were used as a catalyst to eliminate toxic organic dye contamination from wastewater in textile industries. The catalyst's performance was tested by degrading individual dyes as well as mixtures of dyes such as methylene blue (MB), methyl orange (MO), methyl red (MR), and Rose Bengal (RB) at various time intervals. The experimental results show the catalytic high degradation efficiency of different dyes achieving 72-90% rates in 29 s. Moreover, the material displayed excellent recycling stability, maintaining its degradation efficiency over four consecutive runs without any degradation in performance. Overall, the findings of the study suggest that these materials possess efficient catalytic properties, opening avenues toward their use in clean energy alternatives, environmental remediation, and other biological applications.
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The objective of our study is to evaluate quality and thermo oxidative stability of soybean, palm olein, and canola oils and their blends. The binary blends of SO:POO and CO:POO were formulated in a ratio of 75:25 and ternary blend were prepared by blending CO:POO:SO in a ratio of 35:30:35. To monitor the thermal stability, pure oils and their blends were subjected to heating at 180°C for 4 hours. Heating process led to a substantial increase in free fatty acid (FFA), peroxide value (PV), p-anisidine value (p-AV), and saponification value (SV), while iodine value (IV) and oxidative stability index (OSI) were decreased. The principal component analysis (PCA) was also performed. The data indicated that three significant principal components have eigenvalue Ë 1, which collectively constitute 98.8% of the total variance. PC1 contributed mainly with a total value of 50.1%, followed by PC2 (36.2%) and PC3 (12.5%). Results of the present study revealed that the binary and ternary blends exhibited greater oxidative stability than the pure oils. But, the ternary blend CO:POO:SO in a ratio of (35:30:35) was found to be better on the basis of stability and health point of view than other blends. Overall, our study demonstrated the utility of chemometric approaches for evaluating the quality and stability of vegetable oils and their blends, which can be helpful in the selection and optimization of oil blends for food applications.
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Brassica napus , Glycine max , Quimiometría , Aceites de Plantas , Estrés OxidativoRESUMEN
Pomegranate seed oil is a highly unsaturated fatty acid and liable to be oxidized; hence, oil was encapsulated to protect its bioactive materials and increase shelf life with the most common spray drying technique. Whey protein (WP) alone and in combination with Maltodextrin (MD) in the ratio 1:4 weight was utilized. Feed emulsion, droplet size, encapsulation efficiency (EE), moisture, bulk density, powder morphology, particle size, hygroscopicity, and solubility were also analyzed. The spray drying conditions were applied: inlet temperature 125 to 150°C and outlet 60 to 67°C, airflow rate 40-42 m3/mint, feed rate 5.2 g/m, and pump rate 40%. The shape of particles was spherical and round with dents on their surface. After encapsulation, the oxidative stability was monitored at 60°C for 15 days (8 h daily). The smaller droplet size of the emulsion was obtained at 35% total solid contents. WP alone showed better EE (90%) and oxidative stability than the combination of WP and MD as wall materials.
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Desecación/métodos , Almacenamiento de Alimentos , Tecnología de Alimentos/métodos , Aceites de Plantas/química , Granada (Fruta)/química , Semillas/química , Fenómenos Químicos , Emulsiones , Oxidación-Reducción , Polisacáridos , Temperatura , Proteína de Suero de LecheRESUMEN
Tocopherols and tocotrienols in the combined form are known as tocols. Changes of total and individual tocols and sterols concentration of canola oil and deodorizer distillate (DD) during different processing stages were evaluated with the application of gas chromatography (GC) and high-performance liquid chromatography (HPLC). For sterols analysis, GC coupled with flame ionization detector (FID) was used while tocols in canola oil samples and DD, normal phase (NP) HPLC was applied. The results of the present study indicated that levels of total and individual tocols and sterols content were decreased during processing (neutralization to deodorization). Deodorization was found to be the most effective process for the reduction of total sterols and tocols as 55.9% and 34.2%, respectively. A high amount of tocols and sterols was observed in DD. Among tocols and sterols; beta tocopherol (ß-T) and ß-sitosterol were found to be in greater concentration 53.97% and 31.82%, respectively. Therefore, DD could be used as a valuable by-product in the cosmetics and food industries.
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Highly stable, small-sized and evenly distributed solid mercury nanoparticles capped with ibuprofen (Ibu-HgNPs) were prepared via reduction with hydrazine and capped with ibuprofen as a stabilizing agent. Characterization of Ibu-HgNPs was carried out by UV-Vis spectrophotometry and transmission electron microscopy (TEM). The prepared Ibu-HgNPs were immobilized onto a glassy carbon electrode (GCE) and used for the first time as the sensing element for voltammetric determination of low concentrations of acrylamide (AA) in aqueous solutions. Various parameters such as the type of supporting electrolyte, voltammetric mode, frequency, deposition time, stirring rate and initial potential were optimized to obtain the highest peak current of AA. The sensor delivered the best results in combination with the square wave voltammetry (SWV) mode, with good repeatability (relative standard deviation (RSD) of 25 repetitions was 1.4% for 1000 ppb AA). The study further revealed that Ibu-HgNPs are strongly adhered to GCE and hence do not contaminate the environment even after several runs. The newly developed AA sensor provides linear calibration dependence in the range of 100-1300 ppb with an R2 value of 0.996 and limit of detection (LOD) of 8.5 ppb. Negligible interference was confirmed from several organic compounds, cations and anions. The developed sensor was successfully applied for AA determination in various types of environmental real water samples to prove its practical usefulness and applicability.
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Mercurio , Nanopartículas , Acrilamida , Técnicas Electroquímicas , Electrodos , IbuprofenoRESUMEN
Energy plays a key role in each sector of life ranging from basic needs to better standards of life. The world is concerned about 3 ps (population, poverty, and pollution). The increase of these three factors has led the search of the best alternative sources of energies to fulfill all needs of a modern way of life. Biodiesel is a sustainable energy source that has proved to be the best alternate of mineral diesel that possesses similar properties as found in mineral diesel. The recent trend in biodiesel research is towards the use of very cheap feedstock to make this substitute more economical. Following this similar trend, the attempt is made to produce biodiesel from less expensive feedstock namely; residual oil of spent bleaching clay (SBC). In the first step, the quantity of the residual oil that can be recovered followed by assessing its quality was investigated. Afterward, a two-step method of the transesterification process was employed to enhance the yield of methyl ester. The highest yield of 85% was obtained. Key fuel properties were measured and found in good agreement with ASTMD 6751 standards limits. The study also concerned with the practical availability of biodiesel in terms of its stability. For this purpose, produced biodiesel was evaluated for its oxidation stability during 90 days of storage by FT-IR and rancimat methods.
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Biocombustibles , Arcilla/química , Fuentes Generadoras de Energía , Aceites de Plantas , Eliminación de Residuos Líquidos , Esterificación , Ésteres , Oxidación-Reducción , Factores de TiempoRESUMEN
The objective of this study was to investigate the effects of linolenic acid (LA) on oxidation stability of rapeseed oils. Four kinds of rapeseed were harvested by unified cultivation and management in the same geographical conditions, and then four rapeseed oils with different contents of LA were obtained. The effects of linolenic acid and antioxidants (tocopherols and phytosterols) on oxidation stability of rapeseed oils were evaluated. Results showed that rapeseed oil with 5.9% LA was the most stable among four rapeseed oils, followed by commercial rapeseed oil, rapeseed oil with 8.4% LA and rapeseed oil with 10.8% LA. The oxidation stability was negatively correlated with the contents of LA (r = - 0.931, p < 0.01), the polyunsaturated fatty acids (r = - 0.932, p < 0.01), and unsaturated fatty acids (r = - 0.766, p < 0.05). It had no correlation with tocopherols and phytosterols (p > 0.05). In addition, according to the European Union Standards, shelf-life of four rapeseed oils was longer than 30 days in the shelf-life test. Therefore, increasing the LA content in rapeseed oils can be considered as an efficient approach to solve the problem of insufficient LA intake globally.
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The present work is focused on pyrolysis of polystyrene waste for production of combustible hydrocarbons. The experiments were performed in an indigenously made furnace in the presence of a laboratory synthesised copper oxide. The pyrolysis products were collected and characterised. The Fourier transform infrared spectra showed that the liquid fraction contains C-H, C-O, C-C, C=C and O-H bonds, which correspond to various aliphatic and aromatic compounds. Gas chromatography-mass spectrometry traced compounds ranging from C1 to C4 in the gaseous fraction, whereas in the liquid fraction 15 components ranging from C3 to C24 were detected. From the results it has been concluded that CuO as a catalyst not only increased the liquid yield but also reduced the degradation temperature to great extent. Fuel properties of the pyrolysis oil were determined and compared with standard values of commercial fuel oil. The comparison suggested potential application of pyrolysis oil for domestic and commercial use.
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Poliestirenos , Pirólisis , Catálisis , Cobre , Calor , Hidrocarburos , ÓxidosRESUMEN
The presented work demonstrates the preparation of copper nanoparticles (CuNPs) via aqueous leaves extract of Ziziphus mauritiana L. ( Zm ) using hydrazine as a reducing agent. Various parameters such as volume of extract, concentration of hydrazine hydrate, concentration of copper chloride, and pH of the solution were optimized to obtain Ziziphus mauritiana L. leaves extract derived copper nanoparticles ( Zm -CuNPs). Brownish red color was initial indication of the formation of Zm -CuNPs while it was confirmed by surface plasmon resonance (SPR) band at wavelength of 584 nm using ultraviolet-visible (UV-vis) spectroscopy. Synthesized Zm -CuNPs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffractometry (XRD). AFM images showed that the particle size of Zm -CuNPs was from 7 to 17 nm with an average size of 11.3 nm. Fabricated sensor ( Zm -CuNPs) were used as a colorimetric sensor for the detection of Ag + at a linear range between 0.67 × 10 -6 - 9.3 × 10 -6 with R 2 value of 0.992. For real water samples, limit of quantification (LOQ) and limit of detection (LOD) for Ag + was found to be 330 × 10 -9 and 100 × 10 -9 , respectively.
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In the present study copper oxide nanoparticles (CuO NPs) were synthesized using a hydrothermal method with ranolazine as a shape-directing agent. Ranolazine-functionalized CuO NPs were characterized by various analytical techniques such as scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD). The SEM pattern confirmed the morphology of ranolazine-functionalized CuO NPs with well-defined rice-like structures. FTIR spectroscopy confirmed the interaction between CuO NPs and ranolazine. The XRD analysis indicated that the structure of ranolazine-functionalized CuO NPs was monoclinic crystalline and the size ranged between 9 and 18 nm with an average particle size of 12 nm. The smaller size range of CuO NPs gave a large surface area that enhanced the efficiency of these catalysts employed for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) in the H 2 O system. In homogeneous catalysis, results showed that 50 µL of CuO NPs was required in the presence of NaBH4 for 99% reduction of 4-NP in 240 s. On the other hand, for heterogeneous catalysis, 0.5 mg of CuO NPs was used in the presence of NaBH4 for 99% catalytic reduction of 4-NP to 4-AP in 320 s. The rate of reaction for homogeneous catalysis and heterogeneous catalysis was determined from the plots of In(Ct /C0) of 4-NP versus time (s), which showed good linearity with values of 1.3 × 10 -2 and 8.8 × 10 -3 s -1 . respectively. The high-quality catalytic efficiency, good reusability, nontoxic nature, and low cost are favorable properties of the synthesized CuO NPs for use as efficient catalysts for reduction of 4-AP to 4-NP in both homogeneous and heterogeneous media.
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In the present study, high-performance liquid chromatography (HPLC) was used for the separation of tocopherols and triglycerides of processed soybean oil and deodorizer distillate (DD). The results of normal and reversed-phase modes of HPLC revealed that concentrations of tocopherols and triglycerides content were decreased during the neutralization, bleaching, and deodorization processes. The loss of individual tocopherols ranged between 55.16% and 63.25%. During processing, triglycerides containing stearic-oleic-linoleic (SOL) moieties and palmitic-palmitic-linoleic (PPL) fragments showed greater reduction up to 38.14% and 37.69%, respectively. Among tocopherols and triglycerides; γ-tocopherol and oleic-oleic-oleic (OOO) were found to be in greater concentrations 5.53% and 19.78%, respectively in DD as compared to their counterparts. A maximum reduction of tocopherols was observed in the deodorization step. DD was found to be a rich source of bioactive components; therefore, it could be used for many industrial applications including pharmaceutical formulations, cosmetics, and food industries.
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We report a novel, simple, efficient, and green protocol for biogenic synthesis of silver nanoparticles (AgNPs) in aqueous solution using clove (Syzygium aromaticum) extract as a reducing and protecting agent. Ultraviolet-visible (UV-Vis) spectroscopy was employed to monitor the localized surface plasmon resonance (LSPR) band of clove extract-derived AgNPs prepared under various conditions. Fourier-transform infrared (FTIR) spectroscopy analysis provided information about the surface interaction of the clove extract with the AgNPs. Ultrahigh-resolution transmission electron microscopy (UHRTEM) results confirmed the formation of spherical, uniformly distributed clove extract-capped AgNPs with sizes in the range of 2-20 nm (average size: 14.4 ± 2 nm). Powder X-ray diffractometry analysis (PXRD) illustrated the formation of pure crystalline AgNPs. These AgNPs were tested as a colorimetric sensor to detect trace amounts of vinclozolin (VIN) by UV-Vis spectroscopy for the first time. The AgNP-based sensor demonstrated very sensitive and selective colorimetric detection of VIN, in the range of 2-16 µM (R2 = 0.997). The developed sensor was green, simple, sensitive, selective, economical, and novel, and could detect trace amounts of VIN with limit of detection (LOD) = 21 nM. Importantly, the sensor was successfully employed for the determination of VIN in real water samples collected from various areas in Turkey.
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Eucommia ulmoides is a traditional Chinese herb whose seeds can be used to produce edible oils. Fourier transform infrared (FTIR) and synchronous fluorescence spectroscopic (SyFS) spectra of Eucommia ulmoides seed oil (EUSO) are lacking. The relevant functional and fluorescent groups were determined by FTIR and SyFS techniques for discriminating adulteration of EUSO, respectively. FTIR and SyFS spectra of EUSO and six common-used vegetable oils were recorded from 4000-400 cm-1 and 250-700 nm at wavelength interval of 60 nm, respectively. Principal component analysis (PCA), linear discriminant analysis (LDA), cluster analysis (CA) and partial least square (PLS) regression was used for qualitative and quantitative calibration of EUSO adulteration. The FTIR spectral regions of 1429-1377 cm-1 and 1128-1110 cm-1 based on PCA, LDA, and CA, and the PCA of SyFS spectral regions of 600-700 nm and 300-500 nm were evaluated for qualitative differentiation of EUSO adulteration. The recognition rate of PCA validation was found to be 100% by FTIR regions. PLS calibration was optimal by the spectral normalization vector treatment in the two FTIR spectral regions and SyFS spectra were combined with characteristic absorption peak area, which can achieve quantitative detection of EUSO adulteration. The two techniques are useful for EUSO adulteration detection at levels down to 1% and 0.48% (w/w), respectively. The results indicated that spectral information obtained by FTIR and SyFS of EUSO can be used for qualitative and quantitative analysis of EUSO adulteration with the advantages of high sensitivity, simplicity, and rapidness.
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Grasas Insaturadas en la Dieta/análisis , Eucommiaceae/química , Contaminación de Alimentos/prevención & control , Calidad de los Alimentos , Aceites de Plantas/química , Semillas/química , Espectrometría de Fluorescencia/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Calibración , Sensibilidad y EspecificidadRESUMEN
Oral cancer is one of the major cancer types, which has increased sustainably in Southeast Asian countries due to the extensive use of a variety of tobacco and betel nut products. The current study is focused on developing an easy, efficient and cost-effective method for plasma profiling of oral cancer patients and tobacco users in order to have a progressive picture towards oral cancer. For this purpose, the profiling of 147 plasma samples including 67 oral cancer patients' samples, 60 "niswar" (a dipping tobacco product) user samples, and 20 healthy controls using attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), and chemometric analysis was carried out. Fingerprint region (500-1500â¯cm-1) of all three groups showed interesting variations in peaks pattern. From these observations, height ratios of two bands H1646/H1550 and H1080/H1024 with p value of 2.01â¯×â¯10-6 and 8.39â¯×â¯10-7, respectively, showed a pattern between healthy to oral cancer and "niswar" user samples. Chemometric analysis of the data showed a clean separation among the groups. PLS-DA and OPLS-DA models provided 87.7% and 89.5% classification rate, respectively. Area under the curve (AUC) for healthy control, oral cancer and "niswar" users were found to be 0.97, 0.95 and 0.92%, respectively. The results of the present study indicate that FT-IR spectroscopy, in conjunction with chemometric data, can be effectively used for the preliminary differentiation of plasma samples of oral cancer patients, "niswar" users and control samples of healthy persons.
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Metabolómica/métodos , Neoplasias de la Boca/sangre , Productos de Tabaco/efectos adversos , Análisis de Varianza , Análisis Discriminante , Humanos , Análisis de los Mínimos Cuadrados , Análisis Multivariante , Análisis de Componente Principal , Curva ROC , Factores de Riesgo , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
This study describes sensitive determination of atropine using glassy carbon electrodes (GCE) modified with Co3O4 nanostructures. The as-synthesised nanostructures were grown using cysteine (CYS), glutathione (GSH) and histidine (HYS) as effective templates under hydrothermal action. The obtained morphologies revealed interesting structural features, including both cavity-based and flower-shaped structures. The as-synthesised morphologies were noted to actively participate in electro-catalysis of atropine (AT) drug where GSH-assisted structures exhibited the best signal response in terms of current density and over-potential value. The study also discusses the influence of functional groups on the signal sensitivity of atropine electro-oxidation. The functionalisation was carried with the amino acids originally used as effective templates for the growth of Co3O4 nanostructures. The highest increment was obtained when GSH was used as the surface functionalising agent. The GSH-functionalised Co3O4-modified electrode was utilised for the electro-chemical sensing of AT in a concentration range of 0.01-0.46 µM. The developed sensor exhibited excellent working linearity (R2 = 0.999) and signal sensitivity up to 0.001 µM of AT. The noted high sensitivity of the sensor is associated with the synergy of superb surface architectures and favourable interaction facilitating the electron transfer kinetics for the electro-catalytic oxidation of AT. Significantly, the developed sensor demonstrated excellent working capability when used for AT detection in human urine samples with strong anti-interference potential against common co-existing species, such as glucose, fructose, cysteine, uric acid, dopamine and ascorbic acid.
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Atropina/análisis , Cobalto/química , Nanopartículas del Metal/química , Óxidos/química , Atropina/orina , Técnicas Biosensibles , Técnicas Electroquímicas , Electrodos , Glutatión/química , Humanos , Límite de Detección , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos XRESUMEN
Palm fatty acid distillate (PFAD) is cheap and valuable byproduct of edible oil processing industries. This study was designed to characterize PFAD collected from different local oil industries. AOCS methods were used for the determination of physicochemical parameters such as free fatty acid (FFA), saponification value (SV), iodine value (IV), peroxide value (PV) and moisture content. Fatty acid composition was analyzed using GC-MS. Moisture content of samples was found to be in the range between 0.06-7.50%, while FFA, SV, IV and PV were found to be 65.70-94.68%, 195.23-219.64 mg KOH/g, 38.49- 63.10 g I2/100 g, 1.09-16.50 meq/kg, respectively. Mean value of fatty acids in PFAD was found as 0.04% lauric, 0.42% myristic, 41.25% palmitic, 7.29% stearic, 41.58% oleic, 8.95 % linoleic, 0.04% eicosenoic, 0.27% arachidic, 0.07% docosanoic, and 0.05% tetracosanoic acid, respectively. Palmitic acid was found as dominant saturated fatty acid 38.63-45.30%, whereas oleic acid C18:1 n9 was major unsaturated fatty acid 33.54-44.05 % in PFAD.
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Ácidos Grasos no Esterificados/análisis , Industria de Procesamiento de Alimentos , Aceites de Plantas/análisis , Arecaceae , Ácidos Grasos no Esterificados/química , Ácidos Grasos no Esterificados/aislamiento & purificación , Hidrólisis , Pakistán , Aceite de Palma , Aceites de Plantas/química , Aceites de Plantas/aislamiento & purificaciónRESUMEN
This work reports the application of banana peel as a novel bioadsorbent for in vitro removal of five mycotoxins (aflatoxins (AFB1, AFB2, AFG1, AFG2) and ochratoxin A). The effect of operational parameters including initial pH, adsorbent dose, contact time and temperature were studied in batch adsorption experiments. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and point of zero charge (pHpzc) analysis were used to characterise the adsorbent material. Aflatoxins' adsorption equilibrium was achieved in 15 min, with highest adsorption at alkaline pH (6-8), while ochratoxin has not shown any significant adsorption due to surface charge repulsion. The experimental equilibrium data were tested by Langmuir, Freundlich and Hill isotherms. The Langmuir isotherm was found to be the best fitted model for aflatoxins, and the maximum monolayer coverage (Q0) was determined to be 8.4, 9.5, 0.4 and 1.1 ng mg(-1) for AFB1, AFB2, AFG1 and AFG2 respectively. Thermodynamic parameters including changes in free energy (ΔG), enthalpy (ΔH) and entropy (ΔS) were determined for the four aflatoxins. Free energy change and enthalpy change demonstrated that the adsorption process was exothermic and spontaneous. Adsorption and desorption study at different pH further demonstrated that the sorption of toxins was strong enough to sustain pH changes that would be experienced in the gastrointestinal tract. This study suggests that biosorption of aflatoxins by dried banana peel may be an effective low-cost decontamination method for incorporation in animal feed diets.
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Absorción Fisicoquímica , Aflatoxinas/antagonistas & inhibidores , Carcinógenos/antagonistas & inhibidores , Fibras de la Dieta/análisis , Frutas/química , Residuos Industriales/análisis , Musa/química , Adsorción , Aflatoxina B1/análisis , Aflatoxina B1/antagonistas & inhibidores , Aflatoxina B1/química , Aflatoxinas/análisis , Aflatoxinas/química , Alimentación Animal/efectos adversos , Alimentación Animal/análisis , Alimentación Animal/economía , Alimentación Animal/microbiología , Animales , Carcinógenos/análisis , Carcinógenos/química , Fibras de la Dieta/economía , Fibras de la Dieta/uso terapéutico , Contaminación de Alimentos , Industria de Procesamiento de Alimentos/economía , Enfermedades Transmitidas por los Alimentos/etiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Enfermedades Transmitidas por los Alimentos/veterinaria , Concentración de Iones de Hidrógeno , Residuos Industriales/economía , Queensland , TermodinámicaRESUMEN
A transmission FTIR spectroscopic method was developed for direct, inexpensive and fast quantification of paracetamol content in solid pharmaceutical formulations. In this method paracetamol content is directly analyzed without solvent extraction. KBr pellets were formulated for the acquisition of FTIR spectra in transmission mode. Two chemometric models: simple Beer's law and partial least squares employed over the spectral region of 1800-1000 cm(-1) for quantification of paracetamol content had a regression coefficient of (R(2)) of 0.999. The limits of detection and quantification using FTIR spectroscopy were 0.005 mg g(-(1) and 0.018 mg g(-1), respectively. Study for interference was also done to check effect of the excipients. There was no significant interference from the sample matrix. The results obviously showed the sensitivity of transmission FTIR spectroscopic method for pharmaceutical analysis. This method is green in the sense that it does not require large volumes of hazardous solvents or long run times and avoids prior sample preparation.
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Acetaminofén/análisis , Acetaminofén/química , Calibración , Química Farmacéutica , Análisis por Conglomerados , Análisis de los Mínimos Cuadrados , Límite de Detección , Modelos Teóricos , Estándares de Referencia , Espectroscopía Infrarroja por Transformada de Fourier , ComprimidosRESUMEN
A substantially more sensitive and accurate alternative to the single-bounce attenuated total reflectance (SB-ATR) Fourier transform infrared spectroscopic method of AOAC/American Oil Chemists' Society (AOCS) was developed for determination of isolated trans isomers, based on transmission measurements using a technique called spectral reconstitution (SR). The method involves the 1:1.5 dilution of an oil with odorless mineral spirits (OMS) containing a spectral marker. The resulting reduction in sample viscosity facilitates the use of a transmission flow cell, with the spectral marker serving to determine the precise dilution ratio. This allows the spectral contributions of the OMS to be eliminated and a facsimile of the neat oil spectrum to be mathematically reconstituted. The transmission-SR (T-SR) procedure was initially evaluated relative to SB-ATR to track changes in the trans content of mixtures of unhydrogenated canola and a highly hydrogenated sunflower oil (0-30% trans). The results indicated that the T-SR procedure had the potential to serve as the basis of an accurate quantitative method. A subsequent T-SR calibration based on the spectral ratioing principle of the SB-ATR AOACIAOCS method was developed by gravimetrically adding trielaidin (0-4%) to extra virgin olive oil (EVO), producing an excellent linear response with a standard deviation (SD) of < 0.04% trans. Subsequent comparison of SB-ATR and T-SR calibrations developed for 5 oils of different types, each spiked with low levels of trielaidin (0-1.2% trans), clearly indicated that SB-ATR was signal-limited, whereas the T-SR procedure performed well. The EVO calibration was subsequently used to predict the added trans content of these spiked oils, after the spectrum of the corresponding unspiked oil had been ratioed out. The resulting plot of predicted versus added trans was linear, with a slope of 1.02 and an overall SD of <0.05% trans. When the spectra of these oils were ratioed against the spectrum of EVO, the trans predictions for some of the oils were offset by 2-3 percentage points, emphasizing the need for the appropriate trans-free reference oil to perform accurate analyses. If the latter condition is met, then T-SR provides a very simple technique, with the potential for automation, for analysis of oils by transmission spectroscopy, with approximately 20x the sensitivity of the AOAC/AOCS SB-ATR method.