scholarly journals Solid-State Characterization and Compatibility Studies of Penciclovir, Lysine Hydrochloride, and Pharmaceutical Excipients

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3154 ◽  
Author(s):  
Rafaela Z. C. Meira ◽  
Isabela F. B. Biscaia ◽  
Camila Nogueira ◽  
Fabio S. Murakami ◽  
Larissa S. Bernardi ◽  
...  
Keyword(s):  
Solid State ◽  
Ethylenediaminetetraacetic Acid ◽  
Therapeutic Potential ◽  
Chemical Characterization ◽  
Compatibility Studies ◽  
Ambient Conditions ◽  
Scanning Calorimetry ◽  
Crystalline Materials ◽  
Physical And Chemical ◽  
Solid State Characterization

The physical and chemical characterization of the solid-state properties of drugs and excipients is fundamental for planning new formulations and developing new strategies for the treatment of diseases. Techniques such as differential scanning calorimetry, thermogravimetry, X-ray powder diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy are among the most commonly used techniques for these purposes. Penciclovir and lysine are individually used to treat the herpes virus. As such, the development of a formulation containing both drugs may have therapeutic potential. Solid-state characterization showed that both penciclovir and lysine were crystalline materials with melting points at 278.27 °C and 260.91 °C, respectively. Compatibility studies of penciclovir and lysine indicated a possible interaction between these substances, as evidenced by a single melting point at 253.10 °C. The compatibility of several excipients, including ethylenediaminetetraacetic acid, cetostearyl alcohol, sodium lauryl sulphate, di-tert-butyl methyl phenol, liquid petrolatum, methylparaben, nonionic wax, paraffin, propylene glycol, and propylparaben, was evaluated in ternary (penciclovir-lysine-excipient) mixtures (1:1:1, w/w/w) to determine the optimal formulation. The developed formulation was stable under accelerated and ambient conditions, which demonstrated that the interaction between penciclovir and lysine was suitable for the development of a formulation containing both drugs.

scholarly journals Inter-molecular physiochemical characterization for etodolac-hydroxypropyl-β-cyclodextrin polymeric systems in solid and liquid state

2010 ◽  
Vol 8 (4) ◽  
pp. 953-962 ◽  
Author(s):  
Vivek Sinha ◽  
Renu Chadha ◽  
Honey Goel ◽  
Keyword(s):  
Solid State ◽  
Inclusion Complexes ◽  
Liquid State ◽  
Chemical Properties ◽  
Aqueous Solubility ◽  
Phase Solubility ◽  
Scanning Calorimetry ◽  
Polymeric Systems ◽  
Hydrophobic Molecule ◽  
Physical And Chemical

AbstractThe purpose of this study was to explore the utility of hydroxypropyl-β-cyclodextrin (HP-β-CD) systems in forming inclusion complexes with the anti-rheumatic or anti-arthritic drug, etodolac (EDC), in order to overcome the limitation of its poor aqueous solubility. This inclusion system achieved high solubility for the hydrophobic molecule. The physical and chemical properties of each inclusion compound were investigated. Complexes of EDC with HP-β-CD were obtained using the kneading and co-evaporation techniques. Solid state characterization of the products was carried out using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), powder X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Studies in the solution state were performed using UV-Vis spectrophotometry and 1H-NMR spectroscopy. Phase solubility profiles with HP-β-CD employed was found to be AL type. Stability constants (Kc) from the phase solubility diagrams were calculated indicating the formation of 1:1 inclusion complex. Stability studies in the solid state and in liquid state were performed; the possible degradation by RP-HPLC was monitored. The dissolution studies revealed that EDC dissolution rate was improved by the formation of inclusion complexes.

Sustainable Pharmaceutical Preparation Methods and Solid-state analysis Supporting Green Pharmacy

2020 ◽  
Vol 16 ◽  
Author(s):  
Ilma Nugrahani
Keyword(s):  
Solid State ◽  
Pharmaceutical Preparation ◽  
Three Dimensional ◽  
Chemical Properties ◽  
Environmental Damage ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Preparation Methods ◽  
Physical And Chemical ◽  
State Analysis

: Every "entity" or compound has physical and chemical properties as references for the synthesis and determination of the entity's structure. Thermodynamically, solid-state is the most stable matter in the universe and to be the ideal form in structure elucidation of pharmaceutical. The dry treatments become popular, such as mechanochemistry, microwave heating, and the using of deep eutectic agent. These techniques are viewed as the futuristic methods for reducing environmental damage, in line with "green pharmacy" concept. On the other hand, solid-state analysis methods from the simplest to the most sophisticated one have been used in the long decades, but most are for qualitative purposes. Recently many reports have proven that solid-state analysis instruments are reliable and prospective for implementing in the quantitative measurement. Infrared spectroscopy, powder x-ray diffraction, and differential scanning calorimetry have been employed in various kinetics and content determination studies. A revolutionary method developed for structural elucidation is single-crystal diffraction, which is capable of rapidly and accurately determining a three-dimensional chemical structure. Hereby it shown that the accurate, precise, economical, ease, rapid-speed, and reliability of solid-state analysis method are eco-benefits by reducing the reagent, catalyst, and organic solvent.

scholarly journals Solid-State Characterization of Different Crystalline Forms of Sitagliptin

Materials ◽  
2019 ◽  
Vol 12 (15) ◽  
pp. 2351 ◽  
Author(s):  
Nayana C. F. Stofella ◽  
Andressa Veiga ◽  
Laiane J. Oliveira ◽  
Elisa F. Montin ◽  
Itamar F. Andreazza ◽  
...  
Keyword(s):  
Solid State ◽  
Melting Point ◽  
Physicochemical Characterization ◽  
Spectroscopic Techniques ◽  
Scanning Calorimetry ◽  
Pharmaceutical Dosage Form ◽  
Base Form ◽  
Crystalline Forms ◽  
Solid State Characterization

Sitagliptin is an inhibitor of the enzyme dipeptidyl peptidase-4, used for the treatment of type 2 diabetes mellitus. The crystal structure of active pharmaceutical solids determines their physical and chemical properties. The polymorphism, solvates and hydrates can influence the free energy, thermodynamic parameters, solubility, solid-state stability, processability and dissolution rate, besides directly affecting the bioavailability. Thus, the physicochemical characterization of an active pharmaceutical ingredient is required to guarantee the rational development of new dosage forms. In this context, we describe herein the solid-state characterization of three crystalline forms of sitagliptin: sitagliptin phosphate monohydrate, sitagliptin phosphate anhydrous and sitagliptin base form. The investigation was carried out using differential scanning calorimetry (DSC), thermogravimetry (TG)/derivative thermogravimetry (DTG), spectroscopic techniques, X-ray powder diffraction (XRPD) and morphological analysis by scanning electron microscopy. The thermal analysis revealed that during the dehydration of sitagliptin phosphate monohydrate (Tpeak = 134.43 °C, ΔH = −1.15 J g−1) there is a characteristic crystalline transition event, which alters the physicochemical parameters of the drug, such as the melting point and solubility. The crystalline behavior of sitagliptin base form differs from that of sitagliptin phosphate monohydrate and sitagliptin phosphate anhydrous, mainly with regard to the lower temperature of the fusion event. The melting point (Tpeak) values obtained were 120.29 °C for sitagliptin base form, 206.37 °C for sitagliptin phosphate monohydrate and 214.92 °C for sitagliptin phosphate anhydrous. In relation to the thermal stability, sitagliptin phosphate monohydrate and sitagliptin phosphate anhydrous showed a slight difference; however, both are more thermostable than the base molecule. Therefore, through this study it was possible to establish the most suitable crystalline form of sitagliptin for the development of a safe, effective and appropriate pharmaceutical dosage form.

Antibacterial and Anti-Biofilm Biosynthesised Silver and Gold Nanoparticles for Medical Applications: Mechanism of Action, Toxicity and Current Status

2020 ◽  
Vol 17 (2) ◽  
pp. 88-100 ◽  
Author(s):  
Sundos Suleman Ismail Abdalla ◽  
Haliza Katas ◽  
Fazren Azmi ◽  
Mohd Fauzi Mh Busra
Keyword(s):  
Gold Nanoparticles ◽  
Synthesis Method ◽  
Chemical Characterization ◽  
Current Status ◽  
Silver And Gold Nanoparticles ◽  
Physical And Chemical Characterization ◽  
Biosynthesized Agnps ◽  
Physical And Chemical ◽  
Insight Into ◽  
Bio Synthesis

Fast progress in nanoscience and nanotechnology has contributed to the way in which people diagnose, combat, and overcome various diseases differently from the conventional methods. Metal nanoparticles, mainly silver and gold nanoparticles (AgNPs and AuNPs, respectively), are currently developed for many applications in the medical and pharmaceutical area including as antibacterial, antibiofilm as well as anti-leshmanial agents, drug delivery systems, diagnostics tools, as well as being included in personal care products and cosmetics. In this review, the preparation of AgNPs and AuNPs using different methods is discussed, particularly the green or bio- synthesis method as well as common methods used for their physical and chemical characterization. In addition, the mechanisms of the antimicrobial and anti-biofilm activity of AgNPs and AuNPs are discussed, along with the toxicity of both nanoparticles. The review will provide insight into the potential of biosynthesized AgNPs and AuNPs as antimicrobial nanomaterial agents for future use.

scholarly journals Synthesis of short-range ordered aluminosilicates at ambient conditions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Katharina R. Lenhardt ◽  
Hergen Breitzke ◽  
Gerd Buntkowsky ◽  
Erik Reimhult ◽  
Max Willinger ◽  
...  
Keyword(s):  
Short Range ◽  
Spatial Arrangement ◽  
Aluminium Chloride ◽  
Ambient Conditions ◽  
Soils And Sediments ◽  
Submicron Scale ◽  
Mineral Structure ◽  
Temperature And Pressure ◽  
Physical And Chemical ◽  
Microscopic Techniques

AbstractWe report here on structure-related aggregation effects of short-range ordered aluminosilicates (SROAS) that have to be considered in the development of synthesis protocols and may be relevant for the properties of SROAS in the environment. We synthesized SROAS of variable composition by neutralizing aqueous aluminium chloride with sodium orthosilicate at ambient temperature and pressure. We determined elemental composition, visualized morphology by microscopic techniques, and resolved mineral structure by solid-state 29Si and 27Al nuclear magnetic resonance and Fourier-transform infrared spectroscopy. Nitrogen sorption revealed substantial surface loss of Al-rich SROAS that resembled proto-imogolite formed in soils and sediments due to aggregation upon freezing. The effect was less pronounced in Si-rich SROAS, indicating a structure-dependent effect on spatial arrangement of mass at the submicron scale. Cryomilling efficiently fractured aggregates but did not change the magnitude of specific surface area. Since accessibility of surface functional groups is a prerequisite for sequestration of substances, elucidating physical and chemical processes of aggregation as a function of composition and crystallinity may improve our understanding of the reactivity of SROAS in the environment.

scholarly journals Physical and Chemical Characterization of an Oyster Hemagglutinin

1969 ◽  
Vol 244 (15) ◽  
pp. 4128-4135
Author(s):  
R T Acton ◽  
J C Bennett ◽  
E E Evans ◽  
R E Schrohenloher
Keyword(s):  
Chemical Characterization ◽  
Physical And Chemical Characterization ◽  
Physical And Chemical

Miscible blend polyethersulfone/polyimide asymmetric membrane crosslinked with 1,3-diaminopropane for hydrogen separation

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Nur’ Adilah Abdul Nasir ◽  
Ameen Gabr Ahmed Alshaghdari ◽  
Mohd Usman Mohd Junaidi ◽  
Nur Awanis Hashim ◽  
Mohamad Fairus Rabuni ◽  
...  
Keyword(s):  
Separation Efficiency ◽  
Chemical Characterization ◽  
Gas Permeation ◽  
Separation Performance ◽  
Membrane Composition ◽  
Asymmetric Membrane ◽  
Wet Phase Inversion ◽  
Pair Performance ◽  
Improved Performance ◽  
Physical And Chemical

Abstract Efficient purification technology is crucial to fully utilize hydrogen (H2) as the next generation fuel source. Polyimide (PI) membranes have been intensively applied for H2 purification but its current separation performance of neat PI membranes is insufficient to fulfill industrial demand. This study employs blending and crosslinking modification simultaneously to enhance the separation efficiency of a membrane. Polyethersulfone (PES) and Co-PI (P84) blend asymmetric membranes have been prepared via dry–wet phase inversion with three different ratios. Pure H2 and carbon dioxide (CO2) gas permeation are conducted on the polymer blends to find the best formulation for membrane composition for effective H2 purification. Next, the membrane with the best blending ratio is chemically modified using 1,3-diaminopropane (PDA) with variable reaction time. Physical and chemical characterization of all membranes was evaluated using field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR). Upon 15 min modification, the polymer membrane achieved an improvement on H2/CO2 selectivity by 88.9%. Moreover, similar membrane has demonstrated the best performance as it has surpassed Robeson’s upper bound curve for H2/CO2 gas pair performance. Therefore, this finding is significant towards the development of H2-selective membranes with improved performance.

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