AUTOMATED GRAVIMETRIC MANAGEMENT OF SOLUTIONS .2. AUTOMATED GRAVIMETRIC APPROACH TO DIRECT POTENTIOMETRY AND KAPPA NUMBER DETERMINATION

The high-performance microcomputer controlled gravimetric-burette described in Part 1 has been employed to automate some routine analytical procedures, A direct potentiometric determination of fluoride ions in drinking water was developed to include an automatic calibration step, matrix adjustment and sample determination. Also the complex and cumbersome titrimetric procedure far determination of the kappa number (lignin content) in paper pulp, has been automated by using the gravimetric unit and biamperometry, In this last instance, the,automatic standardization of the solutions employed in the determination and the complete automation of the recommended kappa number determination procedure, allows a significant reduction in the amount of reagent consumed. The gravimetric approach to these procedures reveals that the same performance is achieved in terms of precision and accuracy when compared with classic volumetry while the cost associated with the automation decreases owing to the use of the same unit to attain automatic management of up to three different solutions.120112763276

Different extraction methods of biologically active components from propolis: a preliminary study

Abstract Background Propolis is widely used in apitherapy, preparations, and food and beverage additives. Various extraction techniques were applied in the extraction of the biologically active constituents of poplar type propolis in order to compare their efficiency. The methods employed were: traditional maceration extraction, ultrasound extraction (UE), and microwave assisted extraction (MAE). Results The total amounts of extracted phenolics and flavonoids were determined, and the effectiveness of the methods compared. MAE was very rapid but led to the extraction of a large amount of non-phenolic and non-flavonoid material. UE gave the highest percentage of extracted phenolics. Conclusion Compared to the maceration extraction, MAE and UE methods provided high extraction yield, requiring short timeframes and less labour. UE was shown to be the most efficient method based on yield, extraction time and selectivity.</p

Analytical methods applied to diverse types of Brazilian propolis

Propolis is a bee product, composed mainly of plant resins and beeswax, therefore its chemical composition varies due to the geographic and plant origins of these resins, as well as the species of bee. Brazil is an important supplier of propolis on the world market and, although green colored propolis from the southeast is the most known and studied, several other types of propolis from Apis mellifera and native stingless bees (also called cerumen) can be found. Propolis is usually consumed as an extract, so the type of solvent and extractive procedures employed further affect its composition. Methods used for the extraction; analysis the percentage of resins, wax and insoluble material in crude propolis; determination of phenolic, flavonoid, amino acid and heavy metal contents are reviewed herein. Different chromatographic methods applied to the separation, identification and quantification of Brazilian propolis components and their relative strengths are discussed; as well as direct insertion mass spectrometry fingerprinting

Characterization of vegetable oils by electrospray ionization mass spectrometry fingerprinting: Classification, quality, adulteration, and aging

An improved approach for the direct infusion electrospray ionization mass spectrometry (ESI-MS) analysis of vegetable oils is described. The more polar components of the oils, including the fatty acids, are simply extracted with methanol/water (1:1) solution and analyzed by direct infusion ESI-MS in both the negative and positive ion modes. This fingerprinting analysis was applied to genuine samples of olive, soybean, corn, canola, sunflower, and cottonseed oil, to admixtures of these oils, and samples of aged soybean oil. ESI-MS fingerprints in the positive ion mode of the extracts divide the oils into well-defined groups, as confirmed by principal component analysis, whereas ESI-MS fingerprints in the negative ion mode clearly differentiate olive oil from the five other refined oils. The method is also shown to detect aging and adulteration of vegetable oils.77227429743

Metabolic fingerprinting of royal jelly: characterization and proof of authenticity

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Introduction Metabolic fingerprint is a high-throughput screening to provide a sample classification. Objectives Herein, we describe a metabolic fingerpint strategy for proof of authenticity and possible adulteration of natural products. This strategy provides useful and complementary information to food science for content analysis. Methods Twelve samples of commercial royal jelly were analysed by electrospray ionization mass spectrometry (ESI-MS) in the negative mode. ESI-MS/MS was performed for characteristic negatively charged ions. Results Thermostability studies were also performed to royal jelly samples in order to evaluate the change on chemical composition with different times of exposure to heating and storage at room temperature. Conclusion The methodology developed in this work is useful to proof of authenticity and degradation of royal jelly samples using minimum sample preparation and direct injection of extracts.34185190Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Biodiesel Oxidation Monitored by Ambient Desorption/Ionization Mass Spectrometry

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Biodiesel is a renewable source of global interest and one of the most attractive alternatives to partially replace petroleum fuels. Because of its chemical nature, however, biodiesel quality may be more rapidly degraded (than hydrocarbon-based fossil fuels) because of oxidation particularly during long or inappropriate storage. Herein, we show that a direct, rapid, and easy to implement and perform technique, that is, easy ambient sonic-spray ionization mass spectrometry (EASI-MS), can be successfully applied to monitor biodiesel oxidation. Soybean biodiesel stored under different conditions has been monitored by EASI-MS, and markers of oxidation have been identified. A new oxidation index (I-ox) rapidly and easily determined via EASI-MS was proposed.271274557459Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Free and Total Glycerin in Biodiesel: Accurate Quantitation by Easy Ambient Sonic-Spray Ionization Mass Spectrometry

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Quantitation of free and total glycerin content in biodiesel is performed via a simple and direct ambient desorption/ionization mass spectrometric technique. Easy ambient sonic-spray ionization mass spectrometry (EASI-MS) is applied to either the crude or derivatized sample spiked with an internal standard allowing for immediate quantitation of free and total glycerin, a major quality parameter for biodiesel. The linear range obtained by EASI-MS for free glycerin was from 0.005 to 0.100% (m/m), and that for bound glycerin (mono-, di-, and triacylglycerides) was from 0.01 to 0.50% (m/m). These values are in concordance with those required by major regulatory agencies for biodiesel quality control, which are, for free glycerin, a 0.02% (m/m) maximum and, for total glycerin, a 0.25% (m/m) maximum. The simple and fast EASI(+)-MS protocol seems to offer a proper substitute or alternative for the more demanding and time-consuming gas chromatography with flame ionization detection (GC-FID) standard methodology.26530423047Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FINEPConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Quantitation and Quality Control of Biodiesel/Petrodiesel (Bn) Blends by Easy Ambient Sonic-Spray Ionization Mass Spectrometry

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Easy sonic-spray ionization mass spectrometry (EASI-MS) allows for direct and fast MS analysis of samples in ambient conditions with little or no sample preparation, therefore offering unprecedented simplicity, speed, and ease of use EASI-MS has been shown to access the quality, type, and adulteration of biofuels and vegetable oils. Herein, EASI-MS is shown to quantitate and monitor the quality of soybean biodiesel/petrodiesel (Bn) blends. For adulteration, admixture of the parent oil has been tested and nearly instantaneous and direct EASI(+)-MS detection of as little as 1% (w/w) of soybean oil in biodiesel/petrodiesel blends was achieved Linear analytical curves (r > 0.98) were also obtained for the quantitation of Bn blends, and the EASI(+)-MS quantitation results were compared to those obtained by nuclear magnetic resonance (NMR) spectroscopy and mid infrared (IR) spectroscopy.261170187022Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq