Post on 07-May-2015
description
“Critical temperatures for intelligent freeze-
drying”
Nektaria Servi – BTL Instrument Product Manager
Agenda
• History of BTL
• How to determine the Critical temperatures
• Lyostat4 LED Fourth Generation Freeze-Drying
Microscope
• Lyotherm2 – DTA & Impedance Analysis
• Consulting and R&D Services Overview
• Case Studies
• Conclusions
• Questions
History of BTL• Biopharma Technology Ltd (BTL) was founded in 1997
• Sister company of Biopharma Process Systems (BPS)
• To date, BTL has worked with over 1000 products, from
small molecules to proteins, organisms, whole cells,
collagen products, blood and archaeological samples
• BTL has expertise in the formulation of products,
accounting for the lyophilisation steps involved in the
development and/or production process. Acting at early
stage minimises issues otherwise encountered later in
scale-up and downstream process
Why are Critical Temperatures
important in freeze-drying?
• Freeze-drying above the
product critical
temperature can lead to:
– Loss of physical structure
– Incomplete drying (high
moisture content)
– Decreased solubility
– Reduced activity and/or
stability
• Freeze-drying too far
below the product critical
temperature can lead to:
– Poor efficiency
– High running costs
– Longer cycles than
necessary
Critical Temperatures for freeze-
drying
• Collapse Temperature (Tc)
- This is the temperature at which the material softens to
the point of not being able to support its own structure
• Eutectic Temperature (Teu)
- This is the temperature at which the solute material
melts, preventing any structure from forming after the
solvent has been removed
• Glass Transition (Tg)
- This is the temperature at which the glass first exhibits
a change in viscosity from a brittle solid into a soft solid.
Effect on formulation components on
critical temperature
• Higher molecular weight components such as polymers
tend to have higher critical temperatures
• Lower molecular weight components such as salts and
small sugars tend to have lower critical temperatures
• Additionally, crystalline/amorphous mix can have a major
impact on critical temperature:
– Lactose + NaCl (1:1) Tc ≈ -30°C
– Lactose + NaCl (1:0.3) Tc ≈ -45°C
Critical Temperature
Determination
• Using extensive knowledge and experience in
the freeze-drying industry, BTL has developed
two unique analytical instruments. These
bring scientific understanding and a rational
approach to freeze-drying cycle development:
Lyostat4
Freeze-drying microscope
Lyotherm2
DTA & Impedance Analyser
Lyostat4 LED Fourth Generation
Freeze-Drying Microscope
• Lyostat was developed by BTL to provide a rational scientific basis for freeze-drying cycle development. Combined with BTL’s extensive experience in the freeze-drying industry, Lyostat provides a powerful tool for freeze-drying R&D Scientists
• BTL has used Lyostat to analyse over 1000 different formulations, from small drug molecules to large complex biomolecules for biopharmaceutical companies worldwide
Lyostat4 – Freeze-drying
microscope
• Enables real-time observation of the behaviour of your
formulation during freeze-drying
• Enables temperature control between -196°C and
125°C to an accuracy of 0.1°C
• By observing the sample structure during drying as the
temperature is raised, the exact point of collapse or
eutectic melt can be observed under the microscope.
Freeze-drying microscopy
• Enables real-time observation of the behaviour
of your formulation during freeze-drying
• Obtains vital information on the critical
temperatures of your product relevant to freeze-
drying
• Enables you to develop a safe and efficient
freeze-drying cycle specific your product
Benefits of using Lyostat4
• Help to improve old and develop new formulations
• Provide essential data to develop cycles on a rational scientific basis
• Save valuable development time and money
• Enables rapid determination of collapse, melting and eutectic event temperatures
• Archives data and image capture for future reference
• Only 2µl of sample material is required to determine the key parameters
Lyostat4 System Components
System Components
• Lyostat4 Freeze-Drying Cryostage
– Temperature range -196°C to +125°C
– Up to 130°C per min heating/cooling rates
– Silver heating block for high thermal conductivity
• Innovative New Imaging Station with LED lamp
– Purpose Built
– Small benchtop footprint
– Higher resolution than standard compound microscopes
– Tilting lens and camera for easy loading of samples
System Components
• Temperature Control System
– Temperature is controlled by carefully balancing heat
input from a heating element and the precise control
of liquid nitrogen through the silver block
– Temperature is measured to 0.01°C by a Pt100
resistor mounted close to the sample and controlled
to 0.1°C even down to pressures as low as 10-3mBar
System Components
• High Performance Digital Firewire Camera
• Dedicated Digital Image Capture Software
– Displays real-time temperature and pressure information and
gives the user full control heating rate, limit and hold time of up
to 100 ramps within the temperature profile.
– Image capture is integrated with temperature programmer data
capture.
– Images can be loaded into a gallery of either 2,8 or 32 images,
for closer inspection.
• Vacuum Pump
• Vacuum Gauge
• Optional Motorised Vacuum Control System
– Software-controlled motorized valve controls chamber pressure
– Enables close investigation of the effects of pressure on sample
collapse
– Chamber pressure displayed in Torr, microns, mBar and Pa
– Pressure plotted with temperature against time and can be
saved for later analysis.
System Components
Lyostat Key Components
LinkSys
Workstation
Software &
Control
Create MovieView Pictures
Data Overview
This file contains all the
information from the analytical
run
From here you can view the
pictures recorded in a gallery
or put them together to create
a movie (.avi format)
The data chart shows temperature and pressure information throughout the
procedure
Results Data
Data OverviewEach point on the purple image line
represents a single image viewed by
selecting it with the cursor
The single image view enables the user to
draw lines and a size bar to measure
between points of interest on the image
(e.g. ice crystal size)
Date, time, vacuum, temperature and ramp
information are displayed under the image
Results Data
Image Gallery
The gallery view enables
fast sorting of images,
showing how the drying
progresses across a longer
timeframe
Gallery Navigation
Zoom
Image Number
For larger images the gallery can be viewed showing less images – 32, 8 and 2
are available
Results Data
Crust Formation
The black line around the sample
edge is an area of higher solute
concentration that impedes vapour
flow and inhibits drying
Image of a solution showing evidence of crust formation
When the crust ruptures the sample will
dry from the site of the break. In this
case the temperature had been raised
above the sample Tc and so shows
evidence of collapse
Eutectic temperature of a
crystalline material
Lyostat FDM
Screenshots of Lyostat analysis, showing frozen product (1), dried with good structure (2)
and collapse (3)
1
2
3
Lyostat provides you with essential information on the critical
temperatures of your formulation, enabling you to get the best results
from your product
Determination of critical
temperatures
‘Trial and Error’ Cycle
resulting in loss of
product or costly
inefficient cycle
New cycle based
on actual
parameters
Problem Solved
This method is sensitive to endothermic
and exothermic processes
Exotherms
•Crystal transitions
•Crystallization
Endotherms
•Melting
•Transitions in the frozen state
Measures the difference in temperature
between a sample and a reference as heat
is applied or removed from the system.
Differential Thermal Analysis
Lyotherm2 is a unique cutting edge technology pioneeredby Biopharma Technology Ltd with the help of ProfessorLouis Rey as a solution to some of the most difficultchallenges faced by freeze drying R&D scientists
Biopharma Technology Ltd has used Lyotherm2 to analyseover 1000 different formulations, from small drug molecules tolarge complex biomolecules for biopharmaceutical companiesworldwide
Lyotherm2
Impedance analysis is fixed frequency
dielectric analysis
It can provide an indication
of the mobility of a sample in
its frozen state, as
demonstrated in a study
carried out by Professor
Louis Rey*
*Freeze-Drying/ Lyophilization of pharmaceutical and biological products. Vol 137, “Drugs and the
pharmaceutical sciences” series. 2nd edition, Eds L. Rey, J.C. May, Marcel Dekker Inc., New York
Impedance Analysis (ZSinφ)
Benefits of Using Lyotherm2
• Help to improve old and develop new formulations
• Provide essential data to develop cycles on a rational scientific basis
• Save valuable development time and money
• Enables rapid determination of frozen state behaviour
• Archives data for future reference
• Not limited to freeze-drying research but to all frozen state applications
AdvantagesLyotherm2 performs a similar function to DSC (differential scanning
calorimetry) as it has a built in differential thermal analyser which
identifies significant thermal events.
The advantage of Lyotherm2 is that it combines DTA with an Impedance
Analysis (ZSinφ) function, which can provide an indication of the
mobility of a sample in its frozen state. Thus giving a more complete
picture of the events occurring within your product than thermal analysis
alone.
Lyotherm2 System Components
Aluminium heating block
designed to distribute heat
evenly, minimising variation
between samples
DTA Probes (Sample and
Reference)
Impedance probe
(ZSinφ)
Dewar for rapid
cooling by Liquid
Nitrogen
Lyotherm2 Control Box
System Components
Graphical plots of both the ZSinϕ
and DTA values are available
tracking the raw data.
Near-linear cooling rates are
provided by the thermally
distributing design of the sample
holding block.
Data Recording
Real-time analysis of both
ZSinϕ and DTA give results
during the analysis,
updated every 5 seconds.
This provides usable data
before the analysis is
finished.
Data Analysis
The software package
allows you to export
your data directly to
Microsoft Excel for easy
data interpretation and
graph manipulation
Temperature (°°°°C)
Ele
ctr
ica
l Im
pe
da
nc
e Z
(k
Oh
ms
)
De
lta
-T (°° °°
C)
(En
do
Do
wn
)
Data Analysis
Case StudymDSC & Lyotherm 2 Study
Case StudymDSC & Lyotherm 2 Study
Case StudymDSC & Lyotherm 2 Study
Lyotherm2 provides you with essential information on the
critical temperatures of your formulation, enabling you to get
the best results from your product
Determination of critical
temperatures and / or annealing
step requirement
‘Trial and Error’
Cycle resulting in
loss of product
New cycle based
on actual
parameters
Problem Solved
Consulting and R&D
Services
• Formulation Development
• Cycle Development
• Product Characterisation
• Production
• Scale-up: Technology and Cycle Transfer
• New Facility for Cytotoxic Compounds
Products Handled
• Small Molecules (Traditional drugs, small
peptides, crop protection agents
• Large Molecules (Large peptides, proteins, DNA
based reagents)
• Structured Materials (Collagen matrices,
drug/vaccine delivery systems)
• Cellular/Organisms (Bacteria, tissue samples)
Case Study 1 – Cycle Development using FDM,
DTA and impedance analysis
Customer Issue• A customer approached BTL with a product that was being freeze-
dried. Their current cycle duration was 64 hours, which they wanted
to be reduced to increase throughput. FDM, DTA and impedance
analysis was proposed to ascertain the lyophilization and frozen
state behavior of the product, which could then be used to improve
the cycle.
• FDM analysis using the BTL Lyostat and DTA and impedance
analysis using the BTL Lyotherm was carried out on the sample
supplied.
• Once the critical temperatures had been established, three
developmental cycles were undertaken to aim for a cycle with a
duration of no more than 32 hours.
• Following the FDM, DTA and impedance analysis, BTL
recommended that the 25 hour cycle was used to enable a higher
throughput of 5 cycles per week.
Conclusions
• BTL can offer a complete service including
- supply of state-of-the-art high quality systems for FDM and DTA &
Impedance
• BTL Consulting offers
- formulation development
- temperature cycle optimization
- product characterization
Advantages:
• Financial: Formulation of a product that aligns with the most cost
effective lyophilisation process
• Operational: Robust, time-efficient procedure
• Regulatory: Characterised product that mitigates risks
Questions
• Thank you for attending the webinar today
• Please email any questions to:
nservi@biopharma.co.uk
Biopharma House, Winnall Valley Road, Winchester SO23 0LD, UK
+44 (0)1962 841092 intelligentfreezedrying.com