scholarly journals Characterization and Prediction of the Non-Bonded Molecular Interactions between Racemic Ibuprofen and α-Lactose Monohydrate Crystals Produced from Melt Granulation and Slow Evaporation Crystallization

2020 ◽  
Vol 20 (6) ◽  
pp. 1255
Author(s):  
Zulfahmi Lukman ◽  
Nornizar Anuar ◽  
Noor Fitrah Abu Bakar ◽  
Norazah Abdul Rahman

Granulation of racemic ibuprofen (±IBP) and α-lactose monohydrate (ALM) at a slightly lower (±IBP) melting point is an efficient method of binding the active pharmaceutical ingredients (API) and excipient in a binderless condition. However, the co-crystals may be formed from recrystallization of ±IBP on ALM. The objective of this study is to evaluate the tendency of co-crystal formation of granules (3:7 w/w ratio of ±IBP:ALM) by melt granulation process. Second, investigate the recovery of crystals from polyethylene glycol (PEG) 300 solutions containing ±IBP-ALM mixtures. Characterizations of the samples were performed using Fourier Transform Infrared (FTIR) spectroscopy, Differential Scanning Calorimetry (DSC) and Powder X-Ray Diffraction (PXRD) system of the ±IBP-ALM granules produced from melt crystallization and harvested crystals from PEG 300 solution which is produced using slow evaporation crystallization. Crystal analysis of solution containing ±IBP-ALM mixtures revealed that the crystals formed were not co-crystals. Molecular interactions assessment through binding prediction between ±IBP and ALM terminating surfaces was conducted using molecular modelling technique. The result showed that the favorable binding sites of ±IBP molecules were on the surfaces of (0-20), (1-10), (001) and (011) ALM crystals. Successful binding prediction by the attachment energy method has proven that the co-crystal formation between these molecules is theoretically possible.

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1731
Author(s):  
Dorota Kolbuk ◽  
Oliwia Jeznach ◽  
Michał Wrzecionek ◽  
Agnieszka Gadomska-Gajadhur

This study was conducted as a first step in obtaining eco-friendly fibres for medical applications using a synthesised oligomer poly(glycerol succinate) (PGSu) as an additive for synthetic poly(L-lactic acid) (PLLA) and poly (L-lactide-co-caprolactone) (PLCL). The effects of the oligomer on the structure formation, morphology, crystallisation behaviour, and mechanical properties of electrospun bicomponent fibres were investigated. Nonwovens were investigated by means of scanning electron microscopy (SEM), wide angle X-ray scattering (WAXS), differential scanning calorimetry (DSC), and mechanical testing. The molecular structure of PLLA fibres is influenced by the presence of PGSu mainly acting as an enhancer of molecular orientation. In the case of semicrystalline PLCL, chain mobility was enhanced by the presence of PGSu molecules, and the crystallinity of bicomponent fibres increased in relation to that of pure PLCL. The mechanical properties of bicomponent fibres were influenced by the level of PGSu present and the extent of crystal formation of the main component. An in vitro study conducted using L929 cells confirmed the biocompatible character of all bicomponent fibres.


2019 ◽  
Vol 70 (7) ◽  
pp. 2590-2600
Author(s):  
Ioana Cristina Tita ◽  
Lavinia Lupa ◽  
Bogdan Tita ◽  
Roxana Liana Stan ◽  
Laura Vicas

Compatibility studies between active drugs and excipients are substantial in the pharmaceutical technology. Thermal analysis has been extensively used to obtain information about drug-excipient interactions and to perform pre-formulation studies of pharmaceutical dosage forms. The objective of the present study was to evaluate the compatibility of the valsartan (VALS) with pharmaceutical excipients of common use including diluents, binders, disintegrants, lubricants and solubilising agents. Thermogravimetry (TG), derivative thermogravimetry (DTG), but especially differential scanning calorimetry (DSC) were used for a first screening to find small variations in peak temperature and/or their associated enthalpy for six drug/excipient mixtures (starch, cross caramelose sodique, microcrystalline cellulose 102, povidone K30, lactose monohydrate and magnesium stearate), which indicate some degree of interaction. Additional methods using Fourier transformed infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRPD) confirmed the incompatibility of VALS with starch, povidone K30, lactose monohydrate and magnesium stearate. Those excipients should be avoided in the development of solid dosage forms.


2018 ◽  
Vol 10 (5) ◽  
pp. 97
Author(s):  
Stevanus Hiendrawan ◽  
Bambang Veriansyah ◽  
Raymond R. Tjandrawinata

Objective: Pharmaceutical cocrystal is a promising method to improve the solubility of active pharmaceutical ingredients (APIs). Itraconazole (ITZ) is a BCS class II antifungal drug with poor aqueous solubility, therefore an attempt was made to improve the solubility of ITZ using cocrystallization technique. In this work, six novel pharmaceutical cocrystals of ITZ with various coformers, including 4-hydroxybenzoic acid (4HBA), trans-cinnamic acid (TCA), suberic acid (SUB), sebacic acid (SBC), 1-hydroxy-2-naphthoic acid (1H2N), and benzamide (BZD) were prepared.Methods: ITZ cocrystals was prepared by solvent evaporation process. The cocrystals produced were characterized using powder x-ray diffraction (PXRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and fourier transform infrared (FTIR) spectroscopy. Solubility analysis was performed to evaluate the cocrystals.Results: PXRD and DSC analysis revealed that the pattern of all ITZ cocrystals was distinguishable from the individual compounds which indicates the formation of new phase. The solubility of ITZ and its cocrystals from highest to lowest after 24 h in 0.1 N HCl solution (pH 1.2) follows the order ITZ-TCA (1.97-fold), ITZ-SBC (1.09-fold), ITZ, ITZ-1H2N (0.58-fold) and ITZ-4HBA (0.46-fold).Conclusion: This study demonstrates that the selection of coformers has pronounced an impact on the physicochemical properties of ITZ. Based on this study, it can be concluded that cocrystallization offers a valuable way to improve the solubility of ITZ.


CrystEngComm ◽  
2018 ◽  
Vol 20 (22) ◽  
pp. 3105-3116 ◽  
Author(s):  
Roman Svoboda ◽  
Roman Bulánek ◽  
Dušan Galusek ◽  
Roghayeh Hadidimasouleh ◽  
Yadolah Ganjkhanlou

Differential scanning calorimetry and in situ X-ray diffraction analysis were used to study the products and mechanism of crystal formation in VOx–ZrO2 ceramics.


Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2136 ◽  
Author(s):  
Patrycja Garbacz ◽  
Marek Wesolowski

Co-crystals have garnered increasing interest in recent years as a beneficial approach to improving the solubility of poorly water soluble active pharmaceutical ingredients (APIs). However, their preparation is a challenge that requires a simple approach towards co-crystal detection. The objective of this work was, therefore, to verify to what extent a multivariate statistical approach such as principal component analysis (PCA) and cluster analysis (CA) can be used as a supporting tool for detecting co-crystal formation. As model samples, physical mixtures and co-crystals of indomethacin with saccharin and furosemide with p-aminobenzoic acid were prepared at API/co-former molar ratios 1:1, 2:1 and 1:2. Data acquired from DSC curves and FTIR and Raman spectroscopies were used for CA and PCA calculations. The results obtained revealed that the application of physical mixtures as reference samples allows a deeper insight into co-crystallization than is possible with the use of API and co-former or API and co-former with physical mixtures. Thus, multivariate matrix for PCA and CA calculations consisting of physical mixtures and potential co-crystals could be considered as the most profitable and reliable way to reflect changes in samples after co-crystallization. Moreover, complementary interpretation of results obtained using DSC, FTIR and Raman techniques is most beneficial.


2011 ◽  
Vol 181-182 ◽  
pp. 39-42
Author(s):  
Ming Tao Run ◽  
Qing Chang Zhang ◽  
Wen Zhou ◽  
Yu Zhong

The crystal morphology, melt-crystallization and mechanical properties of poly (trimethylene terephthalate)/maleinized poly (octene-ethylene)/organo-montmorillonite nanocomposites were investigated by using polarized optical microscopy (POM), differential scanning calorimetry (DSC) and universal material testing machine, respectively. The results suggest that the nanocomposites form smaller or imperfect microcrystallites with lower melting point due to the influence of OMMT components and the nanocomposites have increased crystallization rate because OMMT is an effective nucleation agent. However, the crystallinity decreases because of the thickening effect of OMMT in the composites. The nanocomposite with 2%OMMT has the largest tensile and impact strength.


2017 ◽  
Vol 737 ◽  
pp. 256-261 ◽  
Author(s):  
Martin Boruvka ◽  
Luboš Bĕhálek

Cellulose is almost inexhaustible source of raw material comprising at least one-third of all biomass matter. Through deconstruction of cellulose hierarchical structure can be extracted highly crystalline cellulose nanocrystals (CNC) with impressive properties. However, the main barrier in the processing of the nanocomposites based on CNC is their inhomogeneous dispersion and distribution in the non-polar polymer matrix. In this paper is this problem addressed by use of novel hydrophobic lignin coated CNC as a biobased nucleation agents in poly (lactic acid) (PLA) nanocomposites. These green nanocomposites based on natural plant derived substances have enormous potential to replace materials originated from non-renewable resources and show promise of providing degradation back into the environment when they are no longer needed. Resulted composites prepared by twin screw extrusion and injection moulding were characterized by means of scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The addition of L-CNC (1, 2 and 3 wt. %) into PLA increased melt crystallization enthalpy and decreases the cold crystallization enthalpy. The degree of crystallinity (cc) increased from 5.6 % (virgin PLA) to 8.5 % (PLA/1-L-CNC), 10.3 % (PLA/2-L-CNC) and 10.7 % (PLA/3-L-CNC). The wide range of degradation temperatures of lignin coating has been observed starting at 100 °C.


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