scholarly journals Solid Dispersions of Anthelmintics and Plant Protection Preparations

Solids ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 60-75
Author(s):  
Salavat S. Khalikov

Because of the rapid development of nanotechnologies, materials, in particular, solid dispersions (SDs), which are actively introduced into the life of modern man, have been obtained. Special progress in this area is observed in industry and medicine. The use of SDs in agriculture is lagging far behind, despite the growing number of scientific papers on this topic. At the same time, the prospects for the introduction of SDs in the agro-industrial complex are obvious. The review presents the results of research on the development of innovative preparations based on SD to protect plants from diseases and pests of cultivated plants, as well as parasiticides to protect animal health based on modern achievements of nanotechnology. One of these technologies is the methods of mechanochemistry, which improve the properties of poorly soluble biologically active substances by their joint mechanical treatment with water-soluble polymers and auxiliary substances.

Author(s):  
Salavat Khalikov

Due to the rapid development of nanotechnologies, materials, in particular , solid dispersions (SDs), which are actively introduced into the life of modern man, have been obtained. Special progress in this area is observed in industry and medicine. The use of SDs in agriculture is lagging far behind, despite the growing number of scientific papers on this topic. At the same time, the prospects for the introduction of SDs in the agro-industrial complex are obvious. The review presents the results of research on the development of innovative preparations based on SD to protect plants from diseases and pests of cultivated plants, as well as parasiticides to protect animal health based on modern achievements of nanotechnology. One of these technologies is the methods of mechanochemistry, which improve the properties of poorly soluble biologically active substances by their joint mechanical treatment with water-soluble polymers and auxiliary substances.


Author(s):  
HUSSEIN K. ALKUFI ◽  
ASMAA M. RASHID

Objective: The aims of the study to enhance solubility and dissolution of famotidine using natural polymer. Solubility study of a drug is one of the contributing factors of its oral bioavailability. The formulation of poorly soluble drugs for oral delivery presents a challenge to the formulation technologists. Methods: The present study has shown that it is possible to raise the solubility for poorly soluble drugs like famotidine, by preparing solid dispersion using natural water-soluble polymer (xyloglucan and hyaluronic acid) as solubilizer through solvent evaporation method. Physical mixture and solid dispersion of famotidine with xyloglucan (XG) or hyaluronic acid in a ratio of 1:1, 1:2, 1:3 were prepared. Solubility study, drug content, dissolution profile and compatibility study were performed for famotidine in solid dispersions XS1, XS2, XS3, HS4, HS5, HS6 as well as in physical mixtures at a ratio 1:1 for both polymer (XG and hyaluronic acid). Results: It was observed that solid dispersions of each drugs showed an increase in dissolution rate in comparison with its pure drug in the ratio of 1:1 (Drug: carrier). It can be concluded that with the care and proper use of xyloglucan, the solubility of drugs poorly soluble can be improved. The prepared solid dispersion showed improvement of drug solubility in all prepared formulas. The best result was obtained with formula XS1 (famotidine: xyloglucan at ratio 1:1) that showed 26 fold increase in solubility compared to the solubility of pure drug. Conclusion: The natural solid dispersion, increased wettability and reduced crystallinity of the drug which leads to improving solubility and dissolution.


2016 ◽  
Vol 52 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Ehsan Adeli

ABSTRACT Azithromycin is a water-insoluble drug, with a very low bioavailability. In order to increase the solubility and dissolution rate, and consequently increase the bioavailability of poorly-soluble drugs (such as azithromycin), various techniques can be applied. One of such techniques is "solid dispersion". This technique is frequently used to improve the dissolution rate of poorly water-soluble compounds. Owing to its low solubility and dissolution rate, azithromycin does not have a suitable bioavailability. Therefore, the main purpose of this investigation was to increase the solubility and dissolution rate of azithromycin by preparing its solid dispersion, using different Polyethylene glycols (PEG). Preparations of solid dispersions and physical mixtures of azithromycin were made using PEG 4000, 6000, 8000, 12000 and 20000 in various ratios, based on the solvent evaporation method. From the studied drug release profile, it was discovered that the dissolution rate of the physical mixture, as the well as the solid dispersions, were higher than those of the drug alone. There was no chemical incompatibility between the drug and polymer from the observed Infrared (IR) spectra. Drug-polymer interactions were also investigated using Differential Scanning Calorimetry (DSC), Powder X-Ray Diffraction (PXRD) and Scanning Election Microscopy (SEM). In conclusion, the dissolution rate and solubility of azithromycin were found to improve significantly, using hydrophilic carriers, especially PEG 6000.


2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Mohamed El-Sakhawy ◽  
Samir Kamel ◽  
Ahmed Salama ◽  
Hebat-Allah Sarhan

Carboxymethyl cellulose acetate butyrate (CMCAB) has gained increasing importance in several fields, particularly in coating technologies and pharmaceutical research. CMCAB is synthesized by esterification of CMC sodium salt with acetic and butyric anhydrides. CMCAB mixed esters are relatively high molecular weight (MW) thermoplastic polymers with high glass transition temperatures (Tg). CMCAB ester is dispersible in water and soluble in a wide range of organic solvents, allowing varied opportunity to the solvent choice. It makes application of coatings more consistent and defect-free. Its ability to slow down the release rate of highly water-soluble compounds and to increase the dissolution of poorly soluble compounds makes CMCAB a unique and potentially valuable tool in pharmaceutical and amorphous solid dispersions (ASD) formulations.


Author(s):  
Magdalena Szaniawska

<p>The form of the active drug administered to patients is important as far as effectiveness of the disease therapy is concerned. From this point of view modifications of medicinal substances are searched for that the obtained compounds have the best physicochemical and pharmacodynamic properties. Pharmaceutical companies allocate significant funds for this type of research. The key property that needs to be improved is the solubility of biologically active substances. This is related to the fact that over 40% of drugs available on the pharmaceutical market are characterized by low solubility in water.</p><p>Thus, the paper describes the most important strategies used in the poorly soluble drug delivery systems, e.g. physical and chemical modifications, formulation based, modification of partition coefficient and lipid systems. The authors discussed various techniques used to enhance solubility of poorly water soluble drugs with their advantages and limitations.</p>


Pharmaceutics ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 130 ◽  
Author(s):  
Joanna Szafraniec ◽  
Agata Antosik ◽  
Justyna Knapik-Kowalczuk ◽  
Krzysztof Chmiel ◽  
Mateusz Kurek ◽  
...  

The self-assembly phenomenon of amphiphiles has attracted particular attention in recent years due to its wide range of applications. The formation of nanoassemblies able to solubilize sparingly water-soluble drugs was found to be a strategy to solve the problem of poor solubility of active pharmaceutical ingredients. Binary and ternary solid dispersions containing Biopharmaceutics Classification System (BCS) class II drug bicalutamide and either Poloxamer®188 or Poloxamer®407 as the surface active agents were obtained by either spray drying or solvent evaporation under reduced pressure. Both processes led to morphological changes and a reduction of particle size, as confirmed by scanning electron microscopy and laser diffraction measurements. The increase in powder wettability was confirmed by means of contact angle measurements. The effect of an alteration of the crystal structure was followed by powder X-ray diffractometry while thermal properties were determined using differential scanning calorimetry. Interestingly, bicalutamide exhibited a polymorph transition after spray drying with the poloxamer and polyvinylpyrrolidone (PVP), while the poloxamer underwent partial amorphization. Moreover, due to the surface activity of the carrier, the solid dispersions formed nanoaggregates in water, as confirmed using dynamic light scattering measurements. The aggregates measuring 200–300 nm in diameter were able to solubilize bicalutamide inside the hydrophobic inner parts. The self-assembly of binary systems was found to improve the amount of dissolved bicalutamide by 4- to 8-fold in comparison to untreated drug. The improvement in drug dissolution was correlated with the solubilization of poorly soluble molecules by macromolecules, as assessed using emission spectroscopy.


Author(s):  
Mohan M Varma ◽  
Satish Kumar P

Gliclazide is an anti-diabetic drug. It is a BCS class-II (poorly water soluble) drug and its bioavailability is dissolution rate limited. The dissolution rate of the drug was enhanced by using the solid dispersion technique. Solid dispersions were prepared using PVP-K30 (polyvinylpyrrolidone) and hydroxypropyl-β-cyclodextrin (HP BCD) as the hydrophilic carriers. The solid dispersions were characterized by using DSC (Differential scanning calorimetry), XRD (X-ray diffractometry) and FTIR (Fourier transform infrared spectroscopy). Solid dispersions were formulated into tablets. The formulated tablets were evaluated for the quality control parameters and dissolution rates. The solid-dispersion tablets enhanced the dissolution rate of the poorly soluble drug. The optimized formulation showed a 3 fold faster drug release compared to the branded tablet. The XRD studies demonstrated the remarkable reduction in the crystallinity of the drug in the solid dispersion. The faster dissolution rate of the drug from the solid dispersion is attributed to the marked reduction in the crystallinity of the drug. The DSC and FTIR studies demonstrated the absence of the drug-polymer interaction.


Author(s):  
Sandeep Doppalapudi ◽  
Vidyadhara Suryadevara ◽  
Sailaja Yallam ◽  
Sowjanya Lakshmi Battula ◽  
Vanya Nayudu

The present work mainly focuses on solubility enhancement of poorly soluble drugs using superdisintegrants. One of such poorly soluble drugs is Atorvastatin, which belongs to the category of statins. Atorvastatin belongs to BCS class – II, which is poorly water soluble and highly permeable. Natural sources are now-a-days playing a key role in pharmaceutical research. They have several pharmaceutical applications. Starches obtained from plants are pharmaceutically useful as binders, diluents, disintegrants and lubricants. Various physical parameters were evaluated. Solid dispersions were prepared using solvent evaporation technique. Where as in solid dispersions, formulations F2 and F5 showed better dissolution rate compared with other formulations. Fourier Transform Infra red spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) studies for optimized formulations revealed that there were no major interactions between the drug and excipients. X-Ray Diffraction (XRD) studies revealed the crystalline and amorphous nature of formulations. Scanning Electron Microscopy (SEM) revealed the surface characteristics. Thus from the present study, it was concluded that Entada scandens seed starch posses superdisintegrant property.


2021 ◽  
Vol 4 (28) ◽  
pp. 159-182
Author(s):  
L.A. Chaikovskaya ◽  
◽  
O.L. Ovsienko ◽  

Phosphorus is an essential plant nutrient involved in plants’ growth and development, accelerated formation of reproductive organs and other important factors for obtaining high and stable crop yields and, therefore, high-quality products. Easily absorbed phosphorus compounds obtained from soil or fertilizers are the most valuable for plants. One of the promising directions for improving the phosphorus nutrition of agricultural crops is biological phosphate mobilization that is carried out by soil microorganisms – bacteria and filamentous fungi (micromycetes). They contribute to the conversion of poorly soluble phosphorus compounds into forms accessible to higher plants. The effect of microorganisms on plants in terms of improving their mineral nutrition, in particular phosphorus, was reviewed in this article. We analysed domestic and foreign literature sources (over the last 15 years) focused on the biodiversity of soil phosphate-mobilizing microorganisms and their influence on converting insoluble phosphate to soluble forms. The features of the mechanisms of biotransformation of organic and mineral phosphates by soil microorganisms and the main criteria for screening effective isolates able to convert poorly soluble phosphorus compounds into forms available for plants were described in detail. This review also demonstrates that several microorganisms belonging to different taxonomic groups (bacteria and micromycetes) are recognized as powerful phosphate solubilizers or bioconverters of poorly soluble phosphorus compounds into water-soluble forms. We also surveyed scientific works, in which the practical application of effective strains of microorganisms that transform unavailable phosphorus compounds into available for plants was studied; and those, in which the role of microorganisms in increasing the availability of phosphorus for agricultural plants and their productivity improvement was demonstrated. A comprehensive description of microbial preparations “Agrofil”, “Biovays”, “Ekophosphorin”, “Ekovital”, “Biophosphorin”, “Albobacterin”, “Polymiksobacterin”, “Agrobacterin”, “Phosphostim”, “Fitostimophos”, “Agromik”, “Baktopin” based on phosphate-mobilizing microorganisms, developed and used in various countries to optimize mineral nutrition of cultivated plants, is given.


2020 ◽  
Vol 10 (1) ◽  
pp. 173-177 ◽  
Author(s):  
, Ikram ◽  
Kapil Kumar

Solid dispersion is a technique which is widely and successfully applied to improve the solubility, dissolution rates and consequently the bioavailability of poorly soluble drugs. Dispersion of one or more active ingredients (hydrophobic) is done with an inert carrier (hydrophilic) at solid-state prepared by fusion method, solvent, and melting solvent method. In this review article, we have focused on the methods of preparation, advantages, disadvantages and characterization of the solid dispersions. Keywords: Solid dispersion; dissolution; solubility.


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