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Influence of drying and granulation process conditions on the characteristics of micronutrient chelates granules

Michałek Bernard, Bizon Katarzyna, Gierczyk Błażej, Wilk Tomasz, Rapp Magdalena

Polish Journal of Chemical Technology

2023

Vol. 25, nr 3

40--49

Fluidized-bed spray granulation (FBSG) enables manufacturing particles with desired characteristics, including particle size distribution (PSD), density, or dust content. This study investigated the effect of selected factors on the granules obtained in a continuous FBSG of chelated fertilizers for foliar applications. The effect of surfactant addition to the solution sprayed into the bed and perturbations of operating parameters on PSD and granules morphology was studied. The experiments were supplemented with calculations based on a population balance equation (PBE). It was shown that granules manufactured with the tenside addition are more regular in shape, and thus less prone to mechanical wear. It was demonstrated that increasing rotational mill speed does contribute to a slight increase in the amount of dust, but in the long term, it does not disturb the regular agglomeration process. The computational results confirm that, despite the complexity of the process, its description with PBE is feasible.

Fluorowany motyw w aktywnych biologicznie peptydomimetykach

Koroniak-Szejn Katarzyna, Rapp Magdalena

Wiadomości Chemiczne

2020

[Z] 74, 3-4

145--179

Incorporation of fluorine atom or fluoroalkyl group into molecules, often induces a remarkable effect upon the physical and chemical properties leading to significant changes of its reactivity [1-5], therefore this modification is often used in the synthesis of drugs and biologically active compounds [6, 7]. The change in reactivity has far-reaching consequences, affects bond energy in the molecule, acidity and alkalinity, hydrogen bond formation and the geometry of the molecule [1-5]. The change in acid-base properties and polarity forced by a fluorine or fluorinated motif in the modified amino acid or peptide molecule has already found numerous applications in bioisosteric mimetics [9]. In addition, using a fluorine atom as a probe, conformation determination and stereochemistry of receptor interaction become more effective due to the possibility of using 19F NMR spectroscopy. The stereoselective introduction of fluorine atoms can therefore be exploited as a conformational tool for the synthesis of shape-controlled functional molecules. Particular attention has been paid to fluorinated peptidomimetics due to the huge variety of their biological activity. Proteins play a significant role in drug design and synthesis. Peptide binding in living organisms is quite labile which is associated with the presence of proteolytic enzymes. Therefore, to prevent protein hydrolysis, new, modified compounds are thought to mimic the properties and functions of peptide bond. These types of compounds are called peptidomimetics. In this monograph, we will focus on the biologically active fluorinated peptidomimetics, in which the amide bond has been replaced by a fluorinated group and thus they can "mimic" peptide bond functions (pseudopeptides). Other peptidomimetics with typical amide bond, but in which the remaining part of the molecule has been modified by introducing a fluorinated group or fluorine (peptide analogs) will also be discussed. The main goal of this work, however, is to demonstrate the beneficial effect of fluorine on the properties of the modified compounds and associated with it consequences. The superior goal of this work, however, is to demonstrate the unique effect of fluorine on the properties of the target compounds and in the design of higher order structures reflecting a more sophisticated molecular construction that broadens biological mimesis.