[PPT] - Outline Introduction o Description of Measurement System o Theory PowerPoint Presentation

SLIDE 1

Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS)

A novel process analytical technology for the development of freeze-drying processes and products

Prof. Geoff Smith

Leicester School of Pharmacy, De Montfort University, United Kingdom

SLIDE 2

2

Through Vial Impedance Spectroscopy

Outline

Introduction
Description of Measurement System
Theory (Dielectric loss mechanisms)
TVIS Applications
Ice Formation and phase separation in freezing
Temperature calibration and prediction
Drying rate estimation
Heat transfer coefficient calculation
End-point determination
Dry Layer resistance and collapse (time permitting)
Acknowledgements

Yowwares Jeeraruangrattana GPO Thailand TVIS pass through on GEA Lyophil dryer, Hurth, Cologne

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Through Vial Impedance Spectroscopy

Introduction to the TVIS System

Impedance spectroscopy characterizes the ability of materials to conduct

electricity under an applied an oscillating voltage (of varying frequency)

Impedance measurements across a vial rather than within the vial
Hence “Through Vial Impedance Spectroscopy”
Features
Single vial “non-product invasive”
Both freezing and drying characterised in a single technique
Non-perturbing to the packing of vials
Stopper mechanism unaffected

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Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) Description of Measurement System

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Through Vial Impedance Spectroscopy

Freeze drying chamber Stimulating voltage Resultant current LyoDEATM measurement software Junction box TVIS system (I to V convertor) Pass-through TVIS measurement vial LyoViewTM analysis software

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Through Vial Impedance Spectroscopy

The designs of various vials that have been

modified with copper foil electrodes (10 mm in height and 3 mm from the base of each container

i. 20 mm crimp-neck vial with 10 ml nominal capacity ii. 20 mm crimp-neck vial with 5 ml nominal capacity iii. screw-neck vial with 5 ml nominal capacity

The different styles of a bespoke pass-through for

TVIS systems

A. Connected via the manifold hose on the outside of the dryer B. Connected via the port on top left side of the door on the dryer C. Connected to a port on the top of the drying chamber

TVIS Measurement System

Adelphi VC010-20C Adelphi VC005-20C Adelphi VCD005

A B C

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7

Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) Dielectric Loss Mechanisms

SLIDE 8

8 Measurement vial Glass Glass

1.1 mm 22 mm 1.1 mm 10 mm

Electronic polarization distortion of electrons relative to the nuclei +

𝐹

Atomic polarization distortion of nuclei across a heteroatom bond by stretching and bending

+

Instantaneous polarization dominant mechanism in the glass wall Electronic polarization distortion of electrons relative to the nuclei +

𝐹

Atomic polarization distortion of nuclei across a heteroatom bond by stretching and bending

+

Instantaneous polarization dominant mechanism in the glass wall

MW (space-charge) polarization at glass wall – sample interface MW (space-charge) polarization at glass wall – sample interface TVIS response for empty vial Space charge polarization (weak frequency dependence) Space charge polarization (weak frequency dependence)

+ + + + + + + +

+

+ + + + + + + + + + + + + + +

TVIS response for empty vial

δ- δ+ δ+

Dipolar polarization re-orientation/alignment of permanent dipoles in liquid water (Debye-like relaxation) Polarization mechanisms in liquid water (relaxation time,  ~ 9 ps at 20oC) Proton-hopping Conduction of protons in liquid water occurs through the Grotthuss "hop-turn" mechanism Conductivity in pure water TVIS response for liquid water

OH− OH− OH− OH− H+ H+ H+ H+ OH− H+

SLIDE 9

9

Dominant at T > 235 K (approx. −40 oC) Generation/migration of L- and D- orientation defects in ice Ih Dominant at T < 235 K (approx. −40 oC) Generation/migration of H3O+/OH− ion pairs (ionic defects) in ice Ih (similar to the Grotthus mechanism) Polarization mechanism in ice TVIS response for frozen water (ice)

Measurement vial Glass Glass

1.1 mm 22 mm 1.1 mm 10 mm

Electronic polarization distortion of electrons relative to the nuclei +

𝐹

Atomic polarization distortion of nuclei across a heteroatom bond by stretching and bending

+

Instantaneous polarization dominant mechanism in the glass wall Electronic polarization distortion of electrons relative to the nuclei +

𝐹

Atomic polarization distortion of nuclei across a heteroatom bond by stretching and bending

+

Instantaneous polarization dominant mechanism in the glass wall

MW (space-charge) polarization at glass wall – sample interface MW (space-charge) polarization at glass wall – sample interface TVIS response for empty vial Space charge polarization (weak frequency dependence) Space charge polarization (weak frequency dependence)

+ + + + + + + +

+

+ + + + + + + + + + + + + + +

TVIS response for empty vial

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Through Vial Impedance Spectroscopy

I. : The polarization of the water dipole in liquid water at 20 ˚C, with a dielectric loss peak frequency of ~ 18 GHz II. : The Maxwell-Wagner (MW) polarization of the glass wall of the TVIS vial at 20 ˚C, with a dielectric loss peak frequency of 17.8 kHz

III. : The dielectric polarization of ice

at −20 ˚C, with a dielectric loss peak frequencies of 2.57 kHz

IV. : The dielectric polarization of ice

at −40 ˚C with a dielectric loss peak frequencies of 537 Hz.

Frozen Water and Dielectric Relaxation of Ice

0.0 0.5 1.0 1.5 2.0 2.5 3.0 1 2 3 4 5 6 7 8 9 10 11 12 13

C′ / pF Log Frequency

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 1 2 3 4 5 6 7 8 9 10 11 12 13

C″ / pF

Log Frequency

20.3 °C

20 °C
40 °C
40 °C
20 °C

20.3 °C (II) (I) (III) (IV)

18 GHz 18 kHz 2.6 kHz 537 Hz

Real part Capacitance Imaginary part Capacitance

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Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) Applications

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Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS)

0.0 0.2 0.4 0.6 0.8 1 2 3 4 5 6

C″/ pF

Log Frequency

FPEAK FPEAK Liquid State Solid State

0.0 0.1 0.2 0.3 0.4 0.5 0.6

1 2 3 4 5 6

C″ / pF

Log Frequency

C″PEAK

increase

Drying time

0.0 0.2 0.4 0.6 0.8 1 2 3 4 5 6

C″ /pF

Log Frequency

38 oC
18 oC

Monitoring Phase Behaviour (ice nucleation temperature and solidification end points by using 𝐺

𝑄𝐹𝐵𝐿

𝐺

𝑄𝐹𝐵𝐿 temperature calibration

for predicting temperature of the product in primary drying Surrogate drying rate (from

𝑒𝐷𝑄𝐹𝐵𝐿

″

𝑒𝑢

) 𝐷′(~ 100 kHz) is highly sensitive to low ice volumes; therefore it could be used for determination end point of primary drying

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Through Vial Impedance Spectroscopy

Imaginary Part of Capacitance Real Part of Capacitance High frequency

Liquid state Liquid state Frozen solid Frozen solid

low frequency Annealing = Re-heating and Re-cooling

Re-heating Re-heating

Intermediate frequency

Re-cooling Re-cooling

low frequency

Primary drying Primary drying

low frequency

TVIS Response Surface (3D-Plot)

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Through Vial Impedance Spectroscopy

Microstructure

Electrode

Glass Wall

𝐷𝑗𝑑𝑓 𝐷𝑣𝑜𝑔𝑠𝑝𝑨𝑓𝑜 𝐷𝐻 𝑆𝑗𝑑𝑓 𝑆𝑣𝑜𝑔𝑠𝑝𝑨𝑓𝑜

Phase Separation in Freezing Step

5%w/v Lactose solution (frozen)

0.0 0.1 0.2 0.3 0.4 0.5 1 2 3 4 5 6

C″ / pF

Log Frequency Water (frozen)

0.0 0.2 0.4 0.6 0.8 1.0 1 2 3 4 5 6

C″ / pF

Log Frequency ice

Unfrozen Fraction Ice peak Ice peak Unfrozen fraction peak Liquid state Liquid state

Electrode

Glass Wall Microstructure

𝐷𝑗𝑑𝑓 𝐷𝐻 𝑆𝑗𝑑𝑓

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Through Vial Impedance Spectroscopy

Data analysing software (LyoView ™)

identifies the peak frequency (𝐺𝑄𝐹𝐵𝐿 ) and peak amplitude (𝐷𝑄𝐹𝐵𝐿

″

) in the imaginary part of the capacitance spectrum

Dielectric loss spectrum

0.00 0.10 0.20 0.30 0.40 1 2 3 4 5 6

C″/pF

Log Frequency

𝐺𝑄𝐹𝐵𝐿 𝐷𝑄𝐹𝐵𝐿

″

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Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) Temperature calibration & Temperature prediction

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17

Temperature Calibration

50
45
40
35
30
25
20
15
10
5

6.0 6.5 7.0 7.5 8.0

Temperature / oC Time /h

Shelf Temp. 𝑼 𝑼𝑫 𝟐 𝑼 𝑼𝑫 𝟑 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1 2 3 4 5 6

C″ / pF

Log Frequency

41.5 °C
15.5 °C

y = -1.0225x2 + 30.106x - 114.74 R² = 0.9999 y = -0.543x2 + 26.718x - 108.5 R² = 0.9999

50
45
40
35
30
25
20
15
10
5

2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8

Temperature /oC Log FPEAK

Bottom electrode

𝑏 𝑐 𝑑

TE

1.02

30.1

114

BE

5.43 x 10-1

26.7

109

Polynomial coefficient from 𝑀𝑝𝑕 𝐺

𝑄𝐹𝐵𝐿 − temperature calibration

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Through Vial Impedance Spectroscopy

Temperature Prediction

45
40
35
30
25
20
15
10
5

5 1 2 3 4 5

Temperature /oC Time / h

𝑈 𝐺𝑄𝐹𝐵𝐿 𝑈𝐹 𝑈 𝐺𝑄𝐹𝐵𝐿 𝐶𝐹 𝑈 𝑈𝐷 2 𝑈 𝑈𝐷 1 Shelf Temperature (𝑈

𝑡)

38
36
34
32
30
28

1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8

Temperature /oC Time / h

𝑈 𝑈𝐷 2 𝑈 𝑈𝐷 1 𝑈 𝐺𝑄𝐹𝐵𝐿 𝐶𝐹 𝑈 𝐺𝑄𝐹𝐵𝐿 𝑈𝐹

Temp. constant
Temp. constant

𝑈(𝑄𝑗=𝑄𝐷@270𝜈𝑐𝑏𝑠) = −33.2 ℃

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Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) Drying rate estimation

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20

Drying Rate Estimation

44
40
36
32
28

1 2 3 4 5

Temperature /oC Time / h

16 17 18 19 20 21 1 2 3 4 5

Ice height (ℎ)/ mm Time / h

𝑈𝑗 𝑈𝑐

Temp. constant

𝑈𝑗= -33.1± 0.05˚C 𝑈𝑐= -29.8± 0.03˚C 𝑈𝑏𝑤𝑕 ~32 ˚C

I II

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21

Drying Rate Estimation

44
40
36
32
28

1 2 3 4 5

Temperature /oC Time / h

16 17 18 19 20 21 1 2 3 4 5

Ice height (ℎ)/ mm Time / h

𝑈𝑗 𝑈𝑐

Temp. constant

𝑈𝑗= -33.1± 0.05˚C 𝑈𝑐= -29.8± 0.03˚C

ℎ(2 ℎ) 19.94 mm ℎ(2.8 ℎ) 18.98 mm

Drying rate during the steady state

Ice density (𝜍𝑗 ) at -32˚C = 0.920 gcm-3

(Calculated ice temperature between 𝑈𝑗 & 𝑈𝑐)

Internal vial diameter (VC010-20C) = 2.21 cm Cross-section area (𝐵) = 3.80 cm2 Ice height at 2 h (ℎ(2 ℎ)) = 19.94 mm Ice height at 2.8 h (ℎ(2.8 ℎ)) = 18.98 mm 𝐸𝑠𝑧𝑗𝑜𝑕 𝑠𝑏𝑢𝑓 (∆𝑛 ∆𝑢 ) = 𝜍𝑗 ∙ 𝐵 ∙ ℎ(𝑢1) − ℎ(𝑢2) 𝑢2 − 𝑢1

𝐸𝑠𝑧𝑗𝑜𝑕 𝑠𝑏𝑢𝑓 = 0.920 𝑕 ∙ 𝑑𝑛−3 × 3.80 𝑑𝑛2 × 19.94 − 18.98 × 10−1𝑑𝑛 2.8 − 2.0 ℎ

= 𝟏. 𝟓𝟑 𝒉 ∙ 𝒊−𝟐

𝑈𝑏𝑤𝑕 ~32 ˚C

TVIS parameters used for determination:

∆𝑛 ∆𝑢 = 0.42 g·h-1

𝑈𝑐= -29.8˚C

SLIDE 22

22

Through Vial Impedance Spectroscopy (TVIS) Heat Transfer Coefficient Determination

273.3 Vial’s base Temperature, 𝑈𝑐(K) 243.3

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24

Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) End-point Determination

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Through Vial Impedance Spectroscopy

0.05 0.07 0.09 0.11 0.13 0.15 3 4 5

C' (Real part)/ pF Log Frequency

0.0 0.5 1.0 1.5 2.0 1 2 3 4 5 6

C' (Real part)/ pF Log Frequency

50 60 70 80 90 1 2 3 4 5 6 7 8 9 10 11 12 13

C' (100 kHz)/ fF Time /h

100 kHz

End−Point Determination (𝑈

𝑡-15 °C and 𝑄 𝑑 400 µbar) Primary Drying time profile

f C' values at a peak

frequency of 100 kHz, i.e. Log F =5

Secondary process Primary process for ice

End−Point Determination (𝑈

𝑡-15 °C and 𝑄 𝑑 400 µbar)

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30

Through Vial Impedance Spectroscopy

50 60 70 80 90 1 2 3 4 5 6 7 8 9 10 11 12 13

60.52 60.54 60.56 60.58 60.60 10.5 11.0 11.5

C' (100 kHz)/ fF Time /h

100 kHz

0.0 0.5 1.0 1.5 2.0 1 2 3 4 5 6

C' (Real part)/ pF Log Frequency

0.060 0.061 3 4 5

C' (Real part)/ pF Log Frequency

Last bit of ice crystal

End−Point Determination (𝑈

𝑡-15 °C and 𝑄 𝑑 400 µbar)

SLIDE 43

43

Through Vial Impedance Spectroscopy

60.52 60.54 60.56 60.58 60.60 10.5 11.0 11.5

C' (100 kHz)/ fF Time /h

100 kHz

0.0 0.5 1.0 1.5 2.0 1 2 3 4 5 6

C' (Real part)/ pF Log Frequency

0.060 0.061 3 4 5

C' (Real part)/ pF Log Frequency

Last ice crystal disappears

End−Point Determination (𝑈

𝑡-15 °C and 𝑄 𝑑 400 µbar)

SLIDE 44

44

Through Vial Impedance Spectroscopy

60.52 60.54 60.56 60.58 60.60 10.5 11.0 11.5

C' (100 kHz)/ fF Time /h

100 kHz

0.060 0.061 3 4 5

C' (Real part)/ pF Log Frequency

0.0 0.5 1.0 1.5 2.0 1 2 3 4 5 6

C' (Real part)/ pF Log Frequency

No change

C' (100 kHz) reaches what looks like a plateau

End−Point Determination (𝑈

𝑡-15 °C and 𝑄 𝑑 400 µbar)

SLIDE 45

45

Through Vial Impedance Spectroscopy

End point determine by high frequency (i.e. 100 kHz for ice) real part capacitance

(i.e. 100 kHz for ice)

Summary

Last bit of ice crystal

60.52 60.53 60.54 60.55 60.56 60.57 60.58 60.59 60.60 10.5 11.0 11.5

C' (100 kHz)/ fF Time /h

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46

Through Vial Impedance Spectroscopy

End point determine by high frequency (i.e. 100 kHz for ice) real part capacitance

(i.e. 100 kHz for ice)

Summary

Last bit of ice crystal 0.15 mg

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47

Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) Product Resistance Determination

SLIDE 48

48

Through Vial Impedance Spectroscopy

Product Resistance (RP) Determination

70
60
50
40
30
Temp. /oC

T(FPEAK) Tcondenser

32 C

0.0 0.1 0.2 0.3

Pressure / torr

0.002 Torr 0.270 Torr

𝑆 𝑞 = 𝑄𝐽𝐷𝐹 − 𝑄CHAMBER 𝑒𝑛 𝑒𝑢 ∙ 𝐵𝑄

ln(𝑄 𝐽𝐷𝐹) = −6144.96 𝑼𝒒 𝒑𝒔 𝑼𝑫 + 24.02 0.0 0.1 0.2 0.3 0.4 0.5 12 13 14 15 16 17 18 19 20

Drying rate / h·g-1 Time/h

1 2 3 4 5 0.2 0.4 0.6 0.8 1

𝑆 ̂𝑞 (cm2·Torr·h·g-1 ) Dry Layer Thickness (cm)

𝑄𝐽𝐷𝐹 − 𝑄CHAMBER ∆𝑛 ∆𝑢 1.75cm2·Torr·h·g-1 Lactose freeze-dried matrix

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Through Vial Impedance Spectroscopy

Middle layer Micro-collapse Top layer Fine pores Bottom layer Full collapse

500X

3 mm

500X 500X

Product Resistance (RP) Determination

1 2 3 4 5 0.2 0.4 0.6 0.8 1

𝑆 ̂𝑞 (cm2·Torr·h·g-1 ) Dry Layer Thickness (cm)

3 mm 𝑆 𝑞 = 𝑄𝐽𝐷𝐹 − 𝑄CHAMBER 𝑒𝑛 𝑒𝑢 ∙ 𝐵𝑄

SLIDE 50

50

Through Vial Impedance Spectroscopy

Through Vial Impedance Spectroscopy (TVIS) Collapse Phenomena

SLIDE 51

51 𝑈(𝑈𝐷) 0.0 0.2 0.4 0.6 0.8 1 2 3 4 5 6

C″ / pF

Log Frequency

22.5 h (-37.8°C) 22.63 h (-37.9°C) 23.43 h (-37°C) 23.8 h (-36.41°C)

Shelf Temperature 𝑈(𝐺𝑄𝐹𝐵𝐿)

45
40
35
30

Temperature /oC

II

𝑈(𝑄𝑗)-36.4 °C 𝑈

𝑕 ′-33.7

°C

I III IV V

0.40 0.45 0.50 0.55 0.60 0.65 0.70 22 23 24 25

C″PEAK / pF

Time / h

Ĉ″peak C″peak

5% Sucrose

𝑒Ĉ𝑄𝐹𝐵𝐿

″

𝑒𝑢 = 0.0380

SLIDE 52

52

5% Sucrose in 0.26% NaCl

45
40
35
30

Temperature /oC

0.20 0.30 0.40 0.50 0.60 22 23 24 25

C″PEAK / pF

Time / h

Ĉ″peak II 𝑈(𝑄𝑗)-36.4 °C 𝑈

𝑕 ′-38.0 °C

I III IV V

𝑒Ĉ𝑄𝐹𝐵𝐿

″

𝑒𝑢 = 0.0644 0.0 0.2 0.4 0.6 1 2 3 4 5 6

C″ / pF

Log Frequency

22.5 h (-37.8°C) 23.17 h (-37.4°C) 23.43 h (-37°C) 23.73 h (-36.6°C)

Shelf Temperature 𝑈(𝐺𝑄𝐹𝐵𝐿) 𝑈(𝑈𝐷)

SLIDE 53

53

5% Sucrose +0.55% NaCl

0.30 0.35 0.40 0.45 0.50 0.55 0.60 22 23 24 25

C″PEAK / pF

Time / h

Ĉ″peak C″peak

45
40
35
30

Temperature /oC

II 𝑈(𝑄𝑗)-36.4 °C 𝑈

𝑕 ′-41.8 °C

I III IV V 𝑒Ĉ𝑄𝐹𝐵𝐿

″

𝑒𝑢 = 0.0864

0.0 0.2 0.4 0.6 1 2 3 4 5 6

C″ / pF

Log Frequency

22.5 h (-38°C) 23.07 h (-38.1°C) 23.37 h (-38°C) 23.9 h (-36.9°C)

Shelf Temperature 𝑈(𝐺𝑄𝐹𝐵𝐿) 𝑈(𝑈𝐷)

SLIDE 54

54

Parameters Unit S-1 S-2 S-3 Component Sucrose Sodium chloride %w/v %w/v 5

5

0.26 5 0.55 𝑼𝒉

′ (DSC)

°C

33.7
38.0
41.8

Temperature stabilization period (Before ramping shelf temperature) 𝑼(𝑮𝑸𝑭𝑩𝑳) Surrogate drying rate (𝒆Ĉ𝑸𝑭𝑩𝑳 𝒆𝒖 ) Structural state h °C pF/h III to IV 23.3 - 23.6

36.0 to -35.6

0.0380 Non-collapse III to IV 23.3 - 23.6

37.0

0.0644 micro-collapse? III to IV 23.1 - 23.6

38.3 to -37.7

0.0864 Micro-collapse Temperature stabilization period (After shelf temperature constant) Surrogate drying rate (𝒆Ĉ𝑸𝑭𝑩𝑳 𝒆𝒖 ) Structural State* h °C pF/h VII to VIII 26.0 - 26.8

26.4 to -25.6

0.2243 Micro-collapse VII to VIII 26.0 – 26.4

30.1 to -30.0

0.1227 Collapse VII to VIII 26.0 -26.2

32.8 to -32.7

0.1569 Collapse

Summary results of sugar- salts solutions

SLIDE 55

55

5% Sucrose in Salt Solutions

0.0 0.2 0.4 0.6 1 2 3 4 5 6

C″ / pF

Log Frequency

23.9 h (-36.9°C) 25.13 h (-33.5°C) 26.13 h (-32.7°C) 26.57 h (-33.4°C)

0.0 0.2 0.4 0.6 1 2 3 4 5 6

C″ / pF

Log Frequency

23.73 h (-36.6°C) 24.97 h (-31.8°C) 26.23 h (-30.1°C) 26.53 h (-28.8°C)

5% sucrose in 0.26% NaCl 5% sucrose in 0.55% NaCl

SLIDE 56

56

Through Vial Impedance Spectroscopy

Limitations

𝐷𝑄𝐹𝐵𝐿

″

and 𝐺𝑄𝐹𝐵𝐿parameters rely on intimate contact of ice cylinder with glass wall

𝐷′(100 kHz) parameter does not dependent on contact and can be used for end

point but relationship between 𝐷′(100 kHz) ice constant is non-linear

Cable length limited to 1m at present
C-TVIS not compatible with front loading system
Incompatible with TCs in same TVIS vial (use fibre optic sensors – INFAP)

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Through Vial Impedance Spectroscopy

Future Work

Development mapping a drying

characteristics

heat transfer coefficients (𝐿𝑊)
dry layer resistance (𝑆𝑄)
Instrument Development
Commercial C-TVIS (2018)
Non-contact TVIS (2018-19)
Micro-well screening
Vial clusters in batch FD
TVIS - Shuttle (2019-20)

Non-invasive real time information for characterising the freeze drying

SLIDE 58

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Through Vial Impedance Spectroscopy

De Montfort University, School of Pharmacy
Evgeny Polygalov: co-inventor of TVIS instrument
Yowwares Jeeraruangrattana. PhD student
Bhaskar Pandya. PhD student
Irina Ermolina. Senior Lecturer

Acknowledgements, Recent Projects & Collaborators

Biopharmaceutical Stability at Room Temperature Analytical Technologies for the Stabilization of Biopharmaceuticals Government Support for industry

LyoDEA

Lyophilization process analytics By dielectric analysis