Freeze-Drying of Pharmaceutical Crystalline and Amorphous Solutes in Vials: Dynamic Multi-Dimensional Models of the Primary and Secondary Drying Stages and Qualitative Features of the Moving Interface

1995 ◽  
Vol 13 (1-2) ◽  
pp. 43-72 ◽  
Author(s):  
A. I. Liapis ◽  
R. Bruttini
2012 ◽  
Vol 48 (2) ◽  
pp. 203-209 ◽  
Author(s):  
Camila Figueiredo Borgognoni ◽  
Joyce da Silva Bevilacqua ◽  
Ronaldo Nogueira de Moraes Pitombo

Transplantation brings hope for many patients. A multidisciplinary approach on this field aims at creating biologically functional tissues to be used as implants and prostheses. The freeze-drying process allows the fundamental properties of these materials to be preserved, making future manipulation and storage easier. Optimizing a freeze-drying cycle is of great importance since it aims at reducing process costs while increasing product quality of this time-and-energy-consuming process. Mathematical modeling comes as a tool to help a better understanding of the process variables behavior and consequently it helps optimization studies. Freeze-drying microscopy is a technique usually applied to determine critical temperatures of liquid formulations. It has been used in this work to determine the sublimation rates of a biological tissue freeze-drying. The sublimation rates were measured from the speed of the moving interface between the dried and the frozen layer under 21.33, 42.66 and 63.99 Pa. The studied variables were used in a theoretical model to simulate various temperature profiles of the freeze-drying process. Good agreement between the experimental and the simulated results was found.


2020 ◽  
pp. 1-15 ◽  
Author(s):  
Getachew Assegehegn ◽  
Edmundo Brito-de la Fuente ◽  
José M. Franco ◽  
Críspulo Gallegos

1994 ◽  
Vol 116 (1) ◽  
pp. 215-220 ◽  
Author(s):  
Shi-Wen Peng ◽  
Guo-Qian Chen

The present work discusses coupled heat and mass transfer during freeze-drying of a rigid product, as well as accelerated freeze-drying where sublimation and desorption occur concurrently. A desorption mushy zone model was developed to describe the desorption drying. An exact solution was obtained for coupled heat and mass transfer with one discrete sublimation moving interface and one desorption mushy zone where mass transfer is controlled by both Fick and Darcy laws. The effects of several parameters on the sublimation and desorption are analyzed and discussed.


2011 ◽  
Vol 100 (2) ◽  
pp. 732-742 ◽  
Author(s):  
Davide Fissore ◽  
Roberto Pisano ◽  
Antonello A. Barresi

Author(s):  
ILYA GULYAKIN ◽  
ANNA LANTSOVA ◽  
LYUDMILA NIKOLAEVA ◽  
MARIA DMITRIEVA ◽  
NATALIYA OBOROTOVA ◽  
...  

Objective: Development of a lyophilized injectable dosage form LCS-1208, an original antitumor drug based on an indolocarbazole derivative. Methods: The prepared solution of the injectable dosage form LCS-1208 is transferred to sterilizing filtration, which is carried out under vacuum on a «Stericup» filter unit with a filter pore size of 0.22 μm. The sterile solution of the injectable dosage form LCS-1208 is poured into sterile vials using a dispenser and lyophilized in a freeze-drying chamber. At the end of drying, the preparation is corked in the chamber of a sublimation unit using a hydraulic device and transferred to crimping with aluminum caps using a seaming machine. Quantitative determination of the drug content was determined by spectrophotometry using a standard sample at λ = 320±2 nm. The pH was determined by potentiometry. Results: A freeze-drying regimen for the injectable dosage form LCS-1208 has been developed. The required solution freezing temperature was established taking into account the presence of 2 eutectic zones: a solution of LCS-1208 in DMSO (-35 ÷-32) °С, an aqueous solution of Kollidon 17PF (-10 ÷-8) °С. As a result of a series of experiments, the optimal lyophilization regime was chosen that does not require preliminary freezing in a low-temperature chamber, with freezing on the shelves of freeze-drying at a temperature of-47 °C without their preliminary cooling. The most acceptable vial filling volume was determined, amounting to 3 ml, and the rate of temperature rise during secondary drying of the preparation was justified. When using the developed regime of lyophilization of the LCS-1208 solution, it was shown that it can be sublimated while preserving the initial qualitative and quantitative characteristics. Conclusion: In this article, using the example of creating a lyophilized injectable dosage form LCS-1208 (the original antitumor drug from the indolocarbazole group), the main problems that arose during the lyophilization of the selected composition of the model solution, as well as ways to improve the process.


Foods ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1488 ◽  
Author(s):  
Dorota Nowak ◽  
Ewa Jakubczyk

Freeze-drying, also known as lyophilization, is a process in which water in the form of ice under low pressure is removed from a material by sublimation. This process has found many applications for the production of high quality food and pharmaceuticals. The main steps of the freeze-drying process, such as the freezing of the product and primary and secondary drying, are described in this paper. The problems and mechanisms of each step of the freeze-drying process are also analyzed. The methods necessary for the selection of the primary and secondary end processes are characterized. The review contains a description of the effects of process conditions and the selected physical properties of freeze-dried materials, such as structural properties (shrinkage and density porosity), color, and texture. The study shows that little attention is given to the mechanical properties and texture of freeze-dried materials obtained from different conditions of the lyophilization process.


2012 ◽  
Vol 30 (11-12) ◽  
pp. 1307-1316 ◽  
Author(s):  
Roberto Pisano ◽  
Davide Fissore ◽  
Antonello A. Barresi

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