Influence of Solvent Evaporation Technique Parameters on Diameter of Submicron Lamivudine-Poly-ε-Caprolactone Conjugate Particles

The size of active pharmaceutical ingredient carrier is one of the key properties considered during design of submicron drug delivery systems. Particle diameter may determine drug biodistribution, cellular uptake, and elimination path. Solvent evaporation technique is a flexible method of particle preparation, in which various macromolecules and drugs may be employed. Parameters of emulsion obtained as first step of particle preparation are crucial in terms of particle size, drug loading, and morphology. The aim of the study was to investigate the influence of emulsion preparation parameters on diameter of resulting particles. Impact of surfactant type and concentration, homogenization time, homogenization rate, phase ratio, and conjugate concentration were evaluated. Model drug lamivudine was covalently bound to polymer and applied in solvent evaporation method in order to overcome issues related to drug loading and provide method-independent incorporation. Synthesized drug–polymer conjugate and obtained particles were evaluated via dynamic light scattering, chromatography, scanning electron microscopy, and spectroscopic methods. Covalent bonding between drug and polymeric chain was confirmed, estimated drug content per milligram of conjugate was 19 μg. Among employed colloid stabilizer, poly(vinyl alcohol) was proven to be most effective. Homogenization rate and surfactant concentration were identified as crucial parameters in terms of particle diameter control.

Physical Characteristics of Edible Film made from Carrageenan and Beeswax Composites through Nanoemulsion Process

A research on producing edible film from composite of carrageenan and beeswax using nanoemulsion<br />process has been conducted, with the objective is to analyze the effect of composite concentrations<br />and homogenization rate on physical characteristics of edible films. The edible films were made using<br />carrageenan concentrations 3.5 and 4.5%, beeswax concentrations 0.2, 0.4, 0.6 and 0.8% and homogenization<br />rates of 2,000 and 3,000 rpm. Physical properties of the edible film were analyzed, i.e: thickness, tensile<br />strength, elongation, water vapor transmission rate and percent of solubility. The result, shows that the<br />composite concentration ratio of carrageenan and beeswax and homogenization rate influence the physical<br />characteristics of edible film. Increased concentrations of composite and homogenization rates have highly<br />significant effect (p&lt;0.01) on decreased of water vapor transmission rate and increased of elongation and<br />percent of solubility, however have no significant effect (p&gt;0.05) on increased of thickness and tensile<br />strength. The best treatment was obtained from composite concentration ratio of carrageenan 4,5% and<br />beeswax 0.8% with homogenization rate 3000 rpm, with the average value of thickness 0.1534 mm, tensile<br />strength 22.44 N/mm2, elongation 22.5%, water vapor transmission rate 25.3411 g/m2/hr and percent of<br />solubility 88%.<br /><br />

Optimization of Conditions for Obtaining Alginate/Olive Oil Capsules for Application in Dairy Industry

Encapsulation is a process of incorporation of bioactive substances in a specific matrix. It results in increasing and/or maintaining of the biological agent concentration in the food matrix or the fermentation system. The encapsulation process is influenced by various factors. The aim of the present work was to investigate the influence of alginate type and concentration, homogenization rate and the oil phase amount in the preparation of capsules rich in olive oil. It has been found that emulsions obtained with medium viscosity alginate were characterized by better stability. To establish the joint influence of the factors was used screening design experiment, the optimization features selected being temperature, centrifugal and microscopic stability. The optimal levels of the factors were established and they we applied for capsule preparation. The obtained capsules showed maximum stability and possibility to be used in dairy product manufacture.

Optimization of a green emulsion stability by tuning homogenization rate

This study has been focused on the development of stable emulsions using ecofriendly ingredients and taking into account that energy requirements should be minimized.