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Biopharma Technology Thermal Analysis InstrumentsLyostatDTA and Impedance analysisLyothermFreeze Drying Microscopy

Lyostat Freeze Drying MicroscopyReal-time observation of the behavior of formulations during freeze dryingBy observing the sample structure the exact point of collapse or eutectic melt can be observed

Lyostat Freeze Drying MicroscopyHelps to improve old and develop new formulationsProvides essential data to develop cycles on a rational scientific basisSave valuable development time and costEnables rapid determination of collapse, melting and eutectic event temperaturesArchives data and image capture for future referenceOnly 2l of sample material is required to determine the key parameters

Lyostat System ComponentsFreeze Drying Cryostage

High Performance Digital USB Camera 2.3MP

Imaging Station with LED Lamp

Temperature Control System

Vacuum Pump, Gauge and Vacuum Control System

Lyostat Sample LoadingTemperature Controlled BlockLight Source (from below)ApertureQuartz cover slip (16 mm dia.)Glass cover slip (13 mm dia.)2l of sampleObjective Lens (usually 10x)

Metal Spacer (70m thick)

Sample Holder

Drop of silicone oil for low temperature lubrication

Lyostat Analysis

Lyostat Sample DryingWhen drying, the sublimation front will move from one side of the sample to the other. In front of it will be the frozen material and behind will be the dried material

The collapse temperature (Tc) is obtained by gradually increasing the temperature until product collapse is observed

Movement of sublimation Front

Frozen Amorphous Material

Dried Amorphous MaterialSublimation Front

Lyostat Sample Drying

Raising the temperature above the Tc of the sample will cause it to undergo collapseA precise Tc can be found by going back and viewing the images recorded during the analytical runFor crystalline products the same method is applied but a eutectic temperature (Teu) is obtained insteadDried Amorphous Material

Collapsed Material

Frozen Amorphous Material

Lyotherm AnalysisDeveloped in collaboration with Professor Louis Rey as a solution to some of the most difficult challenges faced by freeze drying R&D scientistsIt allows to acquire in one single analysis both, DTA (thermal) and Impedance (electric) data.

Lyotherm DTAExotherms

Crystal transitionsCrystallizationEndotherms

MeltingTransitions in the frozen state

DTA measures the difference in temperature between a sample and a reference as heat is applied or removed from the system.This method is sensitive to endothermic and exothermic processes

Lyotherm ImpedanceImpedance (Z) is a more sophisticated version of electrical Resistance (R) analysisIs a combination of Resistance, Inductance and CapacitanceProvides an indication of the mobility of a sample in its frozen state, as demonstrated in a study carried out by Professor Louis Rey*Looking at Z (or more specifically Zsin) can give more detailed information about frozen solute behaviour (Rey, 1999)

Lyotherm Assay ProcedureLoad 3 ml samples into 2 individual sample holders (DTA and Impedance)Load a 3 ml reference (solvent) sample for DTA analysis onlyPlace probes into sample holdersPlace and secure sample holders into blockInitiate data logging using Lyotherm softwareLower heating block into Dewar 1/3 filled with LN2When sample and reference are below -100C, switch on heating

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Lyotherm Assay Procedure

The software package allows you to export your data directly to Microsoft Excel for easy data interpretation and graph manipulation