Skip to main content

LUP Student Papers

LUND UNIVERSITY LIBRARIES

Bead Structure in Freeze-Drying Processes: Analysis Techniques and Detailed Morphology Studies

Pietrzak, Kamil LU (2024) KLGM06 20241
Food Technology and Nutrition (M.Sc.)
Abstract
Freeze drying, also known as lyophilization, is a crucial technology used in
biotechnology and pharmaceutical preparation to preserve enzymes and other sensitive
biological materials. This thesis investigates how different formulations and pellet
dimensions impact the structural integrity of freeze-dried beads, essential for assessing their
properties.

Specifically, the study focuses on sucrose and maltodextrin formulations and their
effects on bead morphology through controlled annealing and freeze-drying processes.
Quench freezing method was designed and then employed to produce uniform beads
for analysis of two sizes: 5mm (large) and 2.5mm (small). Several analytical methods, such
as Differential Scanning Calorimetry (DSC),... (More)
Freeze drying, also known as lyophilization, is a crucial technology used in
biotechnology and pharmaceutical preparation to preserve enzymes and other sensitive
biological materials. This thesis investigates how different formulations and pellet
dimensions impact the structural integrity of freeze-dried beads, essential for assessing their
properties.

Specifically, the study focuses on sucrose and maltodextrin formulations and their
effects on bead morphology through controlled annealing and freeze-drying processes.
Quench freezing method was designed and then employed to produce uniform beads
for analysis of two sizes: 5mm (large) and 2.5mm (small). Several analytical methods, such
as Differential Scanning Calorimetry (DSC), Light microscopy, Stereo microscopy were
utilized to inspect impacts of the designed formulation on structural integrity and
morphology of the freeze-dried pellets.

Key findings indicate that variations in carbohydrate ratios and bead sizes significantly affect the pore structure and morphology of the beads.
The study establishes detailed assessment of changes in accordance with the ratio of excipients and concentration of formulation, as well as pellet dimensions, enhancing the understanding and application of this technique in industrial settings. (Less)
Popular Abstract
Freeze drying, or lyophilization, is a vital technology in the biotechnology and pharmaceutical industries, essential for preserving sensitive biological materials. The process involves freezing the material and then placing it in a vacuum, causing the ice to sublimate directly into vapor, thereby bypassing the liquid phase. This method is crucial for maintaining the stability and extending the shelf life of delicate substances such as enzymes.

One of the primary objectives of the study was to investigate the impact of bead size and formulation on the morphology of the pellets. Another key objective was to develop and optimize protocols for pelletization, annealing, and lyophilization, with the goal of improving the structural outcomes... (More)
Freeze drying, or lyophilization, is a vital technology in the biotechnology and pharmaceutical industries, essential for preserving sensitive biological materials. The process involves freezing the material and then placing it in a vacuum, causing the ice to sublimate directly into vapor, thereby bypassing the liquid phase. This method is crucial for maintaining the stability and extending the shelf life of delicate substances such as enzymes.

One of the primary objectives of the study was to investigate the impact of bead size and formulation on the morphology of the pellets. Another key objective was to develop and optimize protocols for pelletization, annealing, and lyophilization, with the goal of improving the structural outcomes of the beads. Additionally, the study employed advanced analytical techniques such as embedding in silicone elastomer, light microscopy, and differential scanning calorimetry (DSC) to examine the morphological and thermal properties of the freeze-dried beads in detail.
The research utilized the quench-freezing method to produce uniform beads of two sizes, 5mm and 2.5mm. Different ratios of sucrose and maltodextrin were used to prepare the formulations. Microscopy methods were employed to inspect the structural integrity and morphology of the freeze-dried beads - light microscopy and stereomicroscopy.

The findings revealed that variations in carbohydrate ratios and bead sizes significantly affect the pore structure and morphology of the beads. Higher concentrations of carbohydrates tended to produce larger pores. Beads with higher sucrose content showed more pronounced voids in their core, indicating potential structural weaknesses. Additionally, a less porous "skin" layer was observed on the surface of all beads, which was more pronounced in higher carbohydrate concentrations due to the rapid freezing process.

However, the study also highlighted some challenges. There were limitations in the resolution and depth of field of the microscopes used, suggesting a need for enhanced visualization techniques. Additionally, improving automated pore annotation using Python scripts and image processing libraries is recommended to handle lower quality images more effectively. (Less)
Please use this url to cite or link to this publication:
author
Pietrzak, Kamil LU
supervisor
organization
course
KLGM06 20241
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Freeze drying, lyophilization, bead structure, morphology analysis, sucrose, maltodextrin, quench-freezing, Differential Scanning Calorimetry (DSC), light microscopy, carbohydrate formulations, structural integrity, pore structure, pharmaceutical preservation, pharmaceutical formulation
language
English
id
9165674
date added to LUP
2024-06-24 11:41:14
date last changed
2024-06-24 11:41:14
@misc{9165674,
  abstract     = {{Freeze drying, also known as lyophilization, is a crucial technology used in
biotechnology and pharmaceutical preparation to preserve enzymes and other sensitive
biological materials. This thesis investigates how different formulations and pellet
dimensions impact the structural integrity of freeze-dried beads, essential for assessing their
properties.

Specifically, the study focuses on sucrose and maltodextrin formulations and their
effects on bead morphology through controlled annealing and freeze-drying processes.
Quench freezing method was designed and then employed to produce uniform beads
for analysis of two sizes: 5mm (large) and 2.5mm (small). Several analytical methods, such
as Differential Scanning Calorimetry (DSC), Light microscopy, Stereo microscopy were
utilized to inspect impacts of the designed formulation on structural integrity and
morphology of the freeze-dried pellets.

Key findings indicate that variations in carbohydrate ratios and bead sizes significantly affect the pore structure and morphology of the beads. 
The study establishes detailed assessment of changes in accordance with the ratio of excipients and concentration of formulation, as well as pellet dimensions, enhancing the understanding and application of this technique in industrial settings.}},
  author       = {{Pietrzak, Kamil}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Bead Structure in Freeze-Drying Processes: Analysis Techniques and Detailed Morphology Studies}},
  year         = {{2024}},
}