Colloidal Dispersion Stability: Kinetic Modeling of Agglomeration and Aggregation

Gonzatti, Guilherme Kilpp; Netz, Paulo Augusto; Fiel, Luana Almeida; Pohlmann, Adriana Raffin

doi:10.5935/0103-5053.20140290

Cited by 4 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Various methods of analysis are used for kinetic studies of dispersion systems [ 43 , 44 ]. The advantages of the method of laser diffraction of light over other similar methods (nephelometry, turbidimetry) made it possible to apply it to kinetic studies of dissolution.…”

Section: Resultsmentioning

confidence: 99%

Evaluation of Poorly Soluble Drugs’ Dissolution Rate by Laser Scattering in Different Water Isotopologues

et al. 2021

View full text Add to dashboard Cite

The most important task in the design of dosage forms is to modify the pharmaceutical substances structure in order to increase solubilization, targeted delivery, controlled rate of drug administration, and its bioavailability. Screening—laboratory (in vitro) or computer (in silico)—as a procedure for selecting a prototype for the design of a drug molecule, involves several years of research and significant costs. Among a large number of solvents and diluents (alcohol, ether, oils, glycerol, Vaseline) used in the pharmaceutical industry for the manufacture of drugs water finds the greatest application. This is because all biological reactions (reactions in living systems) take place in water and distribution of the fluid in the body and the substances found within is critical for the maintenance of intracellular and extracellular functions. Modern studies in the field of the stable isotopic compositions of natural water and its structure and properties make it possible to use isotopic transformations of the water to improve the pharmacokinetic properties of medicinal substances without previous structural modification. It is known that by replacing any of the atoms in the reacting substance molecule with its isotope, it is possible to record changes in the reactivity, which are expressed as a change in the reaction rate constant, i.e., in the manifestation of the kinetic isotope effect (KIE). The article presents the results of studies on the effect of the kinetic isotope effect of a solvent—water—on increasing the solubility and dissolution rate constants of poorly soluble drugs using laser diffraction spectroscopy. The results of the studies can be successfully implemented in pharmaceutical practice to overcome the poor solubility of medicinal substances of classes II and IV, according to the biopharmaceutical classification system (BCS), in water for pharmaceutical purposes by performing its preliminary and safe isotopic modification.

show abstract

Section: Resultsmentioning

confidence: 99%

Evaluation of Poorly Soluble Drugs’ Dissolution Rate by Laser Scattering in Different Water Isotopologues

et al. 2021

View full text Add to dashboard Cite

show abstract

“…As a result, the surface molecules interact with neighboring particles in an attempt to decrease free energy and increase thermodynamic stability [ 71 ]. This leads to troublesome phenomena such as aggregation and particle fusion [ 72 ]. Aggregation occurs when several particles cluster together and form a group, whereas fusion occurs when multiple nanoparticles interact and combine to form one larger particle.…”

Section: The Need For Lyophilizationmentioning

confidence: 99%

Lyophilization of Nanoparticles, Does It Really Work? Overview of the Current Status and Challenges

Gatto,

Najahi-Missaoui

2023

IJMS

View full text Add to dashboard Cite

Nanoparticles are being increasingly used as drug delivery systems to enhance the delivery to and uptake by target cells and to reduce off-target toxicity of free drugs. However, although the advantages of nanoparticles as drug carriers are clear, there are still some limitations, especially in maintaining their long-term stability. Lyophilization, also known as freeze-drying, has been heavily investigated as a solution to this problem. This strategy has been shown to be effective in increasing both the long-term stability of nanoparticles and the shelf life of the drug product. However, the process is still in need of improvement in several aspects, such as the process parameters, formulation factors, and characterization techniques. This review summarizes the advantages and limitations of nanoparticles for the treatment of disease, advantages and limitations, and the status of the lyophilization of nanoparticles for therapeutic use and provides insight into both the advantages and the limitations.

show abstract

“…As the particle size of a suspension sample decreases down to the nanoscale, the surface to volume ratio and the surface energy increase. In the same way, NCPs tend to be inherently thermodynamically unstable and thus subjected to physical instability resulting in an aggregation and/or fusion of particles [ 42 ]. As a consequence, an increase in particle size and particle size distribution (PSD) is of paramount importance, particularly when NCPs are intended to the intravenous route.…”

Section: Instability Of Nanocapsules In Aqueous Mediamentioning

confidence: 99%

Lyophilization of Nanocapsules: Instability Sources, Formulation and Process Parameters

Degobert

Aydin

2021

Pharmaceutics

View full text Add to dashboard Cite

Polymeric nanocapsules have gained more and more interest in the medical sciences. Their core-shell structure offers numerous advantages, especially regarding their use as drug delivery systems. This review begins by presenting the different intrinsic sources of the instability of nanocapsules. The physical and chemical potential instabilities of nanocapsules reduce their shelf-life and constitute a barrier to their clinical use and to their commercialization. To overcome these issues, lyophilization is often used as a process of choice in the pharmaceutical industry especially when labile compounds are used. The state of the art of lyophilization nanocapsules is reviewed. The formulation properties and the process parameters are discussed for a complete understanding of their impact on the stability and storage of the final dried product. To assess the quality of the dried product, various characterization methods are also discussed.

show abstract

Colloidal Dispersion Stability: Kinetic Modeling of Agglomeration and Aggregation

Cited by 4 publications

References 0 publications

Evaluation of Poorly Soluble Drugs’ Dissolution Rate by Laser Scattering in Different Water Isotopologues

Evaluation of Poorly Soluble Drugs’ Dissolution Rate by Laser Scattering in Different Water Isotopologues

Lyophilization of Nanoparticles, Does It Really Work? Overview of the Current Status and Challenges

Lyophilization of Nanocapsules: Instability Sources, Formulation and Process Parameters

Contact Info

Product

Resources

About