Solid Lipid Microparticles Produced by Spray Congealing: influence of the Atomizer on Microparticle Characteristics and Mathematical Modeling of the Drug Release

Department of Pharmaceutical Sciences, University of Bologna, Bologna, Italy.
Journal of Pharmaceutical Sciences (Impact Factor: 3.01). 01/2009; 99(2):916-31. DOI: 10.1002/jps.21854
Source: PubMed

ABSTRACT The first aim of the work was to evaluate the effect of atomizer design on the properties of solid lipid microparticles produced by spray congealing. Two different air atomizers have been employed: a conventional air pressure nozzle (APN) and a recently developed atomizer (wide pneumatic nozzle, WPN). Milled theophylline and Compritol 888ATO were used to produce microparticles at drug-to-carrier ratios of 10:90, 20:80, and 30:70 using the two atomizers. The results showed that the application of different nozzles had significant impacts on the morphology, encapsulation efficiency, and drug release behavior of the microparticles. In contrast, the characteristics of the atomizer did not influence the physicochemical properties of the microparticles as differential scanning calorimetry, Hot Stage microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy analysis demonstrated. The drug and the lipid carrier presented in their original crystalline forms in both WPN and APN systems. A second objective of this study was to develop a novel mathematical model for describing the dynamic process of drug release from the solid lipid microparticles. For WPN microparticles the model predicted the changes of the drug release behavior with particle size and drug loading, while for APN microparticles the model fitting was not as good as for the WPN systems, confirming the influence of the atomizer on the drug release behavior.

1 Follower
  • [Show abstract] [Hide abstract]
    ABSTRACT: Abstract Purpose: To develop a novel preparation approach of solid Self-Emulsifying Drug Delivery System (s-SEDDS) based on spray congealing as potential drug delivery technology for poorly water-soluble drug Glibenclamide (GBD). Methods: Several systems were formulated using suitable excipients, solid at room temperature, with different hydrophilic-lipophilic balance, such as Myverol, Myvatex, Gelucire®50/13 and Gelucire®44/14. Cremophor®EL and Poloxamer 188 were selected as surfactants and PEG 4000 as co-solvent. Results: The screening of the best carrier for s-SEDDS manufacturing revealed that Gelucire®50/13 had greater performance. Then, surfactant-co-solvent systems were developed. Dissolution studies showed that all the formulations promoted the solubilisation performance of the GBD with respect to pure drug; in particular the formulation containing Gelucire®50/13 and PEG 4000 increased the drug solubilisation of five times. These microparticles showed self-dispersibility within 60 min and micelles dimensions around 360 nm. Conclusions: Spray congealing is a promising novel manufacturing technique of solid self-emulsifying systems.
    Journal of Microencapsulation 11/2014; DOI:10.3109/02652048.2014.985341 · 1.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Spironolactone (SL) is a US Food and Drug Administration-approved drug for the treatment of hypertension and various edematous conditions. SL has gained a lot of attention for treating androgenic alopecia due to its potent antiandrogenic properties. Recently, there has been growing interest for follicular targeting of drug molecules for treatment of hair and scalp disorders using nanocolloidal lipid-based delivery systems to minimize unnecessary systemic side effects associated with oral drug administration. Accordingly, the objective of this study is to improve SL efficiency and safety in treating alopecia through the preparation of colloidal nanostructured lipid carriers (NLCs) for follicular drug delivery. SL-loaded NLCs were prepared by an emulsion solvent diffusion and evaporation method using 23 full factorial design. All of the prepared formulations were spherical in shape with nanometric size range (215.6-834.3 nm) and entrapment efficiency >74%. Differential scanning calorimetry thermograms and X-ray diffractograms revealed that SL exists in amorphous form within the NLC matrices. The drug release behavior from the NLCs displayed an initial burst release phase followed by sustained release of SL. Confocal laser scanning microscopy confirmed the potential of delivering the fluorolabeled NLCs within the follicles, suggesting the possibility of using SL-loaded NLCs for localized delivery of SL into the scalp hair follicles.
    International Journal of Nanomedicine 01/2014; 9:5449-60. DOI:10.2147/IJN.S73010 · 4.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Spray chilling technology (also known as spray cooling and spray congealing technology) has been widely studied and used in the pharmaceutical field. In the food industry, this technique is gaining interest and can become useful because functional food formulations can be developed. Spray chilling is a fat-based system, which involves the addition of the component of interest to a molten lipid carrier, and the resulting mixture is fed through an atomiser nozzle. When the nebulised material is put into contact with the environment, which is cooled below the melting point of the matrix material, the vehicle solidifies (due to heat exchange between the molten material and cold air), and solid lipid microparticles are formed at the same time. This technology is fat based, and lipid carriers, such as wax and oil (e.g. palm oil, beeswax, cocoa butter, and kernel oil) can be used. This encapsulation technique can potentially change the functionality, reduce the hygroscopicity, mask taste or odour, change solubility, and provide physical protection in addition to allowing the controlled release of these ingredients. This low-cost technology is relatively simple to apply and scale up, and it does not require the use of organic solvents and the application of high temperatures in the process. Therefore, spray chilling encapsulation may facilitate the development and production of functional and enriched foods as it may solve some technological problems associated with the use of certain ingredients, such as those that have high reactivity and low stability.
    Food Technology and Biotechnology 04/2013; 51(2):171. · 0.98 Impact Factor

Full-text (2 Sources)

Available from
May 30, 2014