Supplementation of microelements (Mn, Zn, Cu, Cr) to livestock diet is of particular concern. There are various mineral feed additives available on the market. The most frequently used are inorganic feed additives, characterized with low bioavailability and high toxicity. Also, organic feed additives are used, including amino acids chelates, in which bioavailability was greatly improved and toxicity reduced. The problem is high price of these products. Therefore, there is the need to search for new biological mineral feed additives with designed composition, that would be characterized with high bioavailability, low toxicity, low cost and that would also possess a nutritional value. Such a possibility offers biological materials. It was found that biomaterials have metal-binding capabilities. Metal ions may be bound to biomass via either biosorption or bioaccumulation process.
When elaborating technology of the production of feed additives, containing simultaneously various elements, it is necessary to use the tool of multielemental analysis in order to simultaneously analyze the content of Mn, Zn, Cu, Cr. In the present work, ICP-OES multielemental analysis was used to investigate the process of production of mineral feed additives based on the biomass of aquatic plant Lemna minor. The effectiveness of the processes of biosorption and bioaccumulation of microelements by an aquatic plant L. minor was studied. The mechanism of the process as well as equilibrium was investigated with the use of multielemental analysis by ICP-OES Vista-MPX instrument from Varian (Australia). 相似文献
An HPLC-UV/MS method has been developed to identify and quantify flame retardants in post-consumer plastics from waste of electric and electronic equipment (WEEE). Atmospheric pressure chemical ionisation spectra of 15 brominated and phosphate-based flame retardants were recorded and interpreted. The method was applied to detect flame retardant additives in polymer extracts obtained from pressurised liquid extraction of solid polymers. In addition, a screening method was developed for soluble styrene polymers to isolate a flame retardant fraction through the application of gel permeation chromatography (GPC). This fraction was transferred to an online-coupled HPLC column and detected by UV spectroscopy, which allowed a reliable qualitative and quantitative analysis of brominated flame retardants in the polymer solutions. 相似文献
Analysis of low concentration polymer additives has been a challenging problem. The commonly used methods of analysis involve the initial extraction of polymer additives with solvents, often in a Soxhlet apparatus, followed by liquid, size exclusion, or gas chromatography. This paper describes the on-line super-critical fluid extraction (SFE)-supercritical fluid chromatographic (SFC) determination of different additives from low density polyethylene. Cryogenic collection was used as an interface between SFE and SFC to focus the extraction eluate before transfer to an analytical SFC column for quantitative analysis. 相似文献
Temperature‐programmed packed capillary liquid chromatography has been coupled off‐line to Fourier‐transform infrared spectroscopy, utilizing a commercially available interface with a pneumatic nebulizer rebuilt to handle low flow rates at elevated temperatures. The modified interface showed excellent performance with regard to non‐aqueous reversed phase separations of polymer additives, resulting in constructed Gram‐Schmidt chromatograms comparable to chromatograms obtained using UV detection. The spray of the in‐house constructed nebulizer was not influenced by temperature changes of the column effluent, and hence temperature‐programmed gradient separations could be used successfully. The relative standard deviation of peak height was 4.4% (n = 5) and the mass limit of detection was determined to be about 40 ng, using a polymer antioxidant as model compound. The present instrumental coupling has been used for characterization of the antioxidant Irgafos P‐EPQ. 相似文献