–0.01
–0.02
–0.03
Rev Heat Flow (W/g)
–0.04
–0.05
0.00
–0.05
33.74ºC(I)
–0.10
–0.15
–0.20
–0.25
–0.30
Heat Flow (W/g)
–0.25
–0.20
–0.15
Nonrev Heat Flow (W/g)
–0.10
–33.77ºC(I)
–31.75ºC(I)
–0.05
–80
–60
–40
–20
0
20
Temperature (ºC)
Exo Up
Universal V4.5A TA Instruments
File: C:\TA\Data\DSC\2019\300719.003 Run Date: 30-Jul-2019 11:41
Program: Universal V4.5A Ru Number: 3
TA Instruments Thermal Analysis – DSC Standard - Modulated RC
Method Log:
1: Isothermal for 2.00 min
2: Ramp 10.00ºC/min to -90.00ºC
3:Mark end of cycle 1
4:Data storage: Off
5:Modulate +/- 1.00ºC every 60 seconds
6:Isothermal for 8.00 min
7: Data storage: On
8:Sampling interval 1.00 sec/pt
9: Isothermal for 8.00 min
10: Data storage: On
11: Sampling interval 1.00 sec/pt
12:Ramp 3.00ºC/min to 25.00ºC
13:Mark end of cycle 2
14:End of method
DSC
Sample: 5%trehalose in water
Size: 73.8000 mg
Method: MDSC – 3c minramp 1 cmin modulat
–33ºC
Collapse
beginning
File: C:\TA\Data\DSC\2019\3007 19.003
Operator:pm
Run Date: 30-Jul-2019 11:41
Instrument: DSC Q2000 V24.10 Build 122
–37ºC 18µbar sample drying
Sample frozen
(Plane polarised light)
Fig. 1 Thermal analysis of 5% w/v trehalose in water showing (a) FDM profile from frozen (left-hand side
image) to drying (middle image) to collapse at À33
C (right-hand side image) and (b) mDSC profile with heat
flow (À33.7
C), reversing (À31.7
C), and non-reversing (À33.8
C) profiles. Sample 80 mg in high-volume
steel pan, temperature ramp rate 3
C/min with 1
C/min modulation. Exothermic events shown as upward
peaks
118
Kevin R. Ward and Paul Matejtschuk