scholarly journals Transport Properties for Pharmaceutical Controlled-Release Systems: A Brief Review of the Importance of Their Study in Biological Systems

Biomolecules ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 178 ◽  
Author(s):  
Ana C. F. Ribeiro ◽  
Miguel A. Esteso
Keyword(s):  
Controlled Release ◽  
Transport Properties ◽  
Diffusion Coefficients ◽  
Drug Carrier ◽  
Strong Association ◽  
Mutual Diffusion ◽  
Mixed Electrolytes ◽  
Coupled Transport ◽  
Concentration Gradients ◽  
Enhanced Solubility

: The goal of this work was to comprehensive study the transport properties of controlled-release systems for the safe and reliable delivery of drugs. Special emphasis has been placed on the measurement of the diffusion of drugs, alone or in combination with carrier molecules for enhanced solubility and facilitated transport. These studies have provided detailed comprehensive information—both kinetic and thermodynamic—for the design and operation of systems for the controlled release and delivery of drugs. Cyclodextrins are among the most important carriers used in these systems. The basis for their popularity is the ability of these materials to solubilize poorly soluble drugs, generally resulting in striking increases in their water solubilities. The techniques used in these investigations include pulse voltammetry, nuclear magnetic resonance (NMR) and Raman spectroscopy, ultrasonic relaxation, and dissolution kinetics. Transport in these systems is a mutual diffusion process involving coupled fluxes of drugs and carrier molecules driven by concentration gradients. Owing to a strong association in these multicomponent systems, it is not uncommon for a diffusing solute to drive substantial coupled fluxes of other solutes, mixed electrolytes, or polymers. Thus, diffusion data, including cross-diffusion coefficients for coupled transport, are essential in order to understand the rates of many processes involving mass transport driven by chemical concentration gradients, as crystal growth and dissolution, solubilization, membrane transport, and diffusion-limited chemical reactions are all relevant to the design of controlled-release systems. While numerous studies have been carried out on these systems, few have considered the transport behavior for controlled-release systems. To remedy this situation, we decided to measure mutual diffusion coefficients for coupled diffusion in a variety of drug–carrier solutions. In summary, the main objective of the present work was to understand the physical chemistry of carrier-mediated transport phenomena in systems of controlled drug release.

scholarly journals Dependence of Viscosity and Diffusion on β-Cyclodextrin and Chloroquine Diphosphate Interactions

Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1433
Author(s):  
Lenka Musilová ◽  
Aleš Mráček ◽  
Eduarda F. G. Azevedo ◽  
M. Melia Rodrigo ◽  
Artur J. M. Valente ◽  
...  
Keyword(s):  
Diffusion Coefficient ◽  
Diffusion Coefficients ◽  
Mutual Diffusion ◽  
Binary Diffusion Coefficient ◽  
Concentration Gradients ◽  
Cross Diffusion ◽  
Taylor Dispersion Technique ◽  
Dispersion Technique ◽  
And Diffusion ◽  
Chloroquine Diphosphate

Mutual diffusion coefficients of chloroquine diphosphate (CDP) in aqueous solutions both without and with β-cyclodextrin (β-CD) were measured at concentrations from (0.0000 to 0.0100) mol dm−3 and 298.15 K, using the Taylor dispersion technique. Ternary mutual diffusion coefficients (Dik) measured by the same technique are reported for aqueous CDP + β-CD solutions at 298.15 K. The presence of β CD led to relevant changes in the diffusion process, as showed by nonzero values of the cross-diffusion coefficients, D12 and D21. β-CD concentration gradients produced significant co-current coupled flows of CDP. In addition, the effects of β-CD on the transport of CDP are assessed by comparing the binary diffusion coefficient of aqueous CDP solutions with the main diffusion coefficient (D11) measured for ternary {CDP(1) + β-CD(2)} solutions. These observations are supported by viscosity analysis. All data allow to have a better interpretation on the effect of cyclodextrin on the transport behavior of CDP.

Encapsulation of Imatinib in Targeted KIT-5 Nanoparticles for Reducing its Cardiotoxicity and Hepatotoxicity

2020 ◽  
Vol 20 (16) ◽  
pp. 1966-1980
Author(s):  
Jaleh Varshosaz ◽  
Saeedeh Fardshouraki ◽  
Mina Mirian ◽  
Leila Safaeian ◽  
Setareh Jandaghian ◽  
...  
Keyword(s):  
Controlled Release ◽  
Side Effects ◽  
Kinase Inhibitor ◽  
Lymphoblastic Leukemia ◽  
Drug Carrier ◽  
Free Drug ◽  
Jurkat Cells ◽  
Targeted Nanoparticles ◽  
Inhibitor Drug ◽  
Histopathological Results

Background: Using imatinib, a tyrosine kinase inhibitor drug used in lymphoblastic leukemia, has always had limitations due to its cardiotoxicity and hepatotoxicity side effects. The objective of this study is to develop a target-oriented drug carrier to minimize these adverse effects by the controlled release of the drug. Methods: KIT-5 nanoparticles were functionalized with 3-aminopropyltriethoxysilane and conjugated to rituximab as the targeting agent for the CD20 positive receptors of the B-cells. Then they were loaded with imatinib and their physical properties were characterized. The cell cytotoxicity of the nanoparticles was studied by MTT assay in Ramos (CD20 positive) and Jurkat cell lines (CD20 negative) and their cellular uptake was shown by fluorescence microscope. Wistar rats received an intraperitoneal injection of 50 mg/kg of the free drug or targeted nanoparticles for 21 days. Then the level of aspartate Aminotransferase (AST), alanine Aminotransferase (ALT), Alkaline Phosphatase (ALP) and Lactate Dehydrogenase (LDH) were measured in serum of animals. The cardiotoxicity and hepatotoxicity of the drug were also studied by hematoxylin and eosin staining of the tissues. Results: The targeted nanoparticles of imatinib showed to be more cytotoxic to Ramos cells rather than Jurkat cells. The results of the biochemical analysis displayed a significant reduction in AST, ALT, ALP, and LDH levels in animals treated with targeted nanoparticles, compared to the free drug group. By comparison with the free imatinib, histopathological results represented less cardiotoxicity and hepatotoxicity in the animals, which received the drug through the current designed delivery system. Conclusion: The obtained results confirmed that the rituximab targeted KIT-5 nanoparticles are promising in the controlled release of imatinib and could decrease its cardiotoxicity and hepatotoxicity side effects.

scholarly journals Formulation and development of metformin-loaded microspheres using Khaya senegalensis (Meliaceae) gum as co-polymer

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Chukwuebuka H. Ozoude ◽  
Chukwuemeka P. Azubuike ◽  
Modupe O. Ologunagba ◽  
Sejoro S. Tonuewa ◽  
Cecilia I. Igwilo
Keyword(s):  
Controlled Release ◽  
Sodium Alginate ◽  
Release Kinetics ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Metformin Hydrochloride ◽  
Scanning Calorimetry ◽  
Khaya Senegalensis

Abstract Background Khaya gum is a bark exudate from Khaya senegalensis (Maliaecae) that has drug carrier potential. This study aimed to formulate and comparatively evaluate metformin-loaded microspheres using blends of khaya gum and sodium alginate. Khaya gum was extracted and subjected to preformulation studies using established protocols while three formulations (FA; FB and FC) of metformin (1% w/v)-loaded microspheres were prepared by the ionic gelation method using 5% zinc chloride solution as the cross-linker. The formulations contained 2% w/v blends of khaya gum and sodium alginate in the ratios of 2:3, 9:11, and 1:1, respectively. The microspheres were evaluated by scanning electron microscopy, Fourier transform-infrared spectroscopy, differential scanning calorimetry, entrapment efficiency, swelling index, and in vitro release studies. Results Yield of 28.48%, pH of 4.00 ± 0.05, moisture content (14.59% ± 0.50), and fair flow properties (Carr’s index 23.68 ± 1.91 and Hausner’s ratio 1.31 ± 0.03) of the khaya gum were obtained. FTIR analyses showed no significant interaction between pure metformin hydrochloride with excipients. Discrete spherical microspheres with sizes ranging from 1200 to 1420 μm were obtained. Drug entrapment efficiency of the microspheres ranged from 65.6 to 81.5%. The release of the drug from microspheres was sustained for the 9 h of the study as the cumulative release was 62% (FA), 73% (FB), and 80% (FC). The release kinetics followed Korsmeyer-Peppas model with super case-II transport mechanism. Conclusion Blends of Khaya senegalensis gum and sodium alginate are promising polymer combination for the preparation of controlled-release formulations. The blend of the khaya gum and sodium alginate produced microspheres with controlled release properties. However, the formulation containing 2:3 ratio of khaya gum and sodium alginate respectively produced microspheres with comparable controlled release profiles to the commercial brand metformin tablet.

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