Hand Sanitizer Analysis:
Application Notebook
The Covid-19 pandemic has led to an increase in usage of hand sanitizers as emphasis on disease
prevention focuses on cleanliness and personal hygiene. Ensuring the purity and potency of hand
sanitizers is paramount to their safety and efficacy. As a result, laboratories are seeking methods
and techniques for analyzing hand sanitizers and their common ingredients, including ethanol and
isopropanol. This workbook serves as a compendium of Shimadzu’s methods for analysis supporting
this industry and the fight against Covid-19.
Table of Contents
Gas Chromatography Techniques
• Analysis of Volatile Impurities in Anhydrous Ethanol and Ethanol for Disinfection in Accordance
with the Purity Test set by the Pharmacopoeias (JP, USP, EP)
• Alcohol Determination of Sanitizer Gel in accordance with USP<611> using He carrier gas
• Determination of Ethanol and Isopropanol Content in Hand Sanitizers Using Nitrogen Carrier Gas
Molecular Spectroscopy Techniques
• Quick and Easy Analysis of Alcohol Content in Hand Sanitizer by FTIR Spectroscopy
• Ethanol Content and Pass/Fail Judgement in Hand Sanitizers Using FTIR Spectroscopy
• Measurement of Impurities in Ethanol Using UV-Vis Spectrophotometry
Solutions for
Hand Sanitizer Analysis
Application Notebook
Which technique is right for my needs?
This flow chart outlines recommended methods and instrumentation for purity and potency of alcohols
and finished hand sanitizers. First, determine if you are analyzing finished products or individual
ingredients. Then, determine which parameter(s) you need to assess.
Application
News
No.
G331
Ethanol has antimicrobial properties and is sold as a
disinfectant product at optimized concentrations.
Quality control of the alcohol as a medical product is
carried out through verification testing procedures as
stipulated
in
each
monograph
of
the
Pharmacopoeias. Guided by the International Council
for Harmonization on Technical Requirements for
Pharmaceuticals for Human Use(ICH), the Japanese
(JP),
United
States
(USP)
and
European
(EP)
pharmacopoeias share roughly the same verification
testing procedures for anhydrous ethanol and
ethanol for disinfection. The Chinese Pharmacopoeia
(ChP) also adopts a similar testing method.
Methanol, acetaldehyde, acetal and benzene are
among the volatile impurities to be monitored. An
instrument is required to detect benzene down to the
specified 2 vol ppm limit or lower and also obtain a
good
resolution
between
acetaldehyde
and
methanol. This article presents the analysis of volatile
impurities in accordance with the purity test (3) of the
Japanese pharmacopoeia.
A. Miyamoto, T. Wada
Testing Method
The sample solution and standard solutions (1) – (4) *1
were prepared in accordance with Supplement I to the
Japanese Pharmacopoeia Seventeenth Edition. For
ethanol for disinfection, purified water was added to 83
mL of anhydrous ethanol*2 to make up to a total volume
of 100 mL.
System Suitability Test
When 1 μL of the standard solution (2) is injected into
GC
under
the
conditions
shown
in
Table
1,
acetaldehyde and methanol
should elute with
acetaldehyde ahead of methanol and their resolution
needs to be no less than 1.5. In this experiment, the
resolution of acetaldehyde and methanol was greater
than 1.5 (Fig. 1 and Fig. 2). The calculation for the
resolution was performed as per the JP, USP and EP
Pharmacopoeias.
Gas Chromatography
Analysis of Volatile Impurities in Anhydrous Ethanol
and Ethanol for Disinfection in Accordance with the
Purity Test set by the Pharmacopoeias (JP, USP, EP)
Model
:
Nexis™ GC-2030/AOC-20i Plus
Column
:
ZB-624 (30 m, 0.32 mm I.D., df=1.8 µm)
Column Temp.
:
40 °C (12 min)-10 °C/min-240 °C (10 min）
Total
：42 min
Detector
:
FID
Carrier Gas Control
:
Constant linear velocity
Carrier Gas
:
He, 35 cm/sec
Injection Temp.
:
200 °C
Detector Temp.
:
280 °C
Injection Mode
:
Split ＊2
Split Ratio
:
1:20
Injection Volume
:
1 µL
Analysis Conditions
Table 1 lists the instrument configurations and the
analysis conditions used in this experiment.
Table 1 Instrument Configuration and Analysis Conditions
*2: The insert for splitless use for GC-17A (P/N
：221-41544) was used.
The insert was packed with 10 mg of deactivated glass wool (P/N:
221-48600).
分離度の平均値（n=3）
2.01（JP、EP）
1.82（USP）
データ1
データ2
データ3
0.0
1.0
2.0
3.0
4.0
min
Ac
et
al
de
hy
de
M
et
ha
no
l
Fig. 1 Chromatogram of Standard Solution (2) for Anhydrous
Ethanol (Overlaid Data from Three Continuous Analyses)
Average resolution (n=3)
2.01 (JP, EP)
1.82 (USP)
Data 1
Data 2
Data 3
分離度の平均値（n=3）
1.74（JP 、EP）
1.68（USP）
データ1
データ2
データ3
0.0
1.0
2.0
3.0
4.0
min
Ac
et
al
de
hy
de
M
et
ha
no
l
Fig. 2 Chromatogram of Standard Solution (2) for Ethanol for
Disinfection (Overlaid Data from Three Continuous Analyses)
Average resolution (n=3)
1.74 (JP, EP)
1.68 (USP)
Data 1
Data 2
Data 3
*1: This article uses the JP nomenclature. The USP and EP counterparts are as
listed below.
*2: FUJIFILM Wako Pure Chemical Corporation’s Japanese Pharmacopoeia-
grade ethanol (99.5)
JP
USP
EP
Sample
Sample solution A
Test solution(a)
Sample Solution
Sample solution B
Test solution(b)
Standard Solution (1)
Standard solution A Reference solution(a)
Standard Solution (2)
Standard solution B Reference solution(b)
Standard Solution (3)
Standard solution C Reference solution(c)
Standard Solution (4)
Standard solution D Reference solution(d)
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G331
Application
News
Shimadzu Corporation
For Research Use Only. Not for use in diagnostic procedure.
This publication may contain references to products that are not available in your country. Please contact us to check the availability of these
products in your country.
The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of Shimadzu.
Shimadzu disclaims any proprietary interest in trademarks and trade names used in this publication other than its own.
See http://www.shimadzu.com/about/trademarks/index.html for details.
The information contained herein is provided to you "as is" without warranty of any kind including without limitation warranties as to its
accuracy or completeness. Shimadzu does not assume any responsibility or liability for any damage, whether direct or indirect, relating to the
use of this publication. This publication is based upon the information available to Shimadzu on or before the date of publication, and subject
to change without notice.
© Shimadzu Corporation, 2020
Fig. 3 Chromatograms of Anhydrous Ethanol, Sample Solution and Standard Solutions (1) – (4)
Analysis of Volatile Impurities
Methanol, acetaldehyde, acetal and benzene are analyzed to verify that the volumes of these impurities will not exceed
those specified. The chromatograms of the samples (i.e. anhydrous ethanol and ethanol for disinfection), the sample
solution and standard solutions (1) – (4) are shown in Fig.3 and Fig. 4. The peak areas and volumes of the volatile
impurities are listed in Table 2. The data obtained were confirmed to meet the three purity criteria listed below.
Conclusion
System suitability test and analysis of volatile
impurities were carried out in accordance with the
purity test of ethanol in the JP (USP, EP) using NexisTM
GC-2030 gas chromatograph.
The results met the criteria set for testing anhydrous
ethanol and ethanol for disinfection.
NexisTM GC-2030 equipped with highly sensitive FID-
2030 had enough sensitivity to detect even the most
demanding volatile impurity like benzene.
First Edition: Jul. 2020
1.
The peak area of methanol obtained with the sample be no greater than 1/2 times that of methanol with the standard
solution (1).
2.
When calculating the amounts of the volatile impurities, the total amount of acetaldehyde and acetal (equation 1) be no
more than 10 vol ppm as acetaldehyde and the amount of benzene (equation 2) be no more than 2 vol ppm.
3.
The total area of all other impurities peak with the sample solution be no larger than the peak area of 4-methylpentan2-ol*1.
*1: Peaks with areas less than 3 % of that of 4-methyl-2-pentanol
should not be included. In this experiment, no target peaks
were detected in the sample solution.
*2: For abbreviations of A
E, BE, CE, AT, CT and BT, see refer to Table 2.
アセトアルデヒド及びアセタールの量の和（vol ppm）=
（式1）＊2
+
30 × CE × 44.05
(CT – C E) × 118.2
10 × AE
AT ー AE
ベンゼンの量（vol ppm）=
（式2）
2BE
BT - BE
Total amount of acetaldehyde and acetal (vol ppm)
(Equation 1) *2
Amount of benzene (vol ppm)
(Equation 2)
無水エタノール
試料溶液（4-Methylpentane-2-ol 添加）
標準溶液（1）
標準溶液（2）
標準溶液（3）
標準溶液（4）
SN比 11.7
uV
Ac
et
al
de
hy
de
Ac
et
al
4-
M
et
hy
lp
en
ta
ne
-2
-o
l
Be
nz
en
e
M
et
ha
no
l
Be
nz
en
e
0.0
2.5 5.0 7.5 10.0 12.5 15.0 17.5 min
9.5
10.0
10.5 11.0
min
Anhydrous ethanol
Sample solution (spiked with 4-Methylpentane-2-ol)
Standard solution (1)
Standard solution (2)
Standard solution (3)
Standard solution (4)
SN ratio 11.7
消毒用エタノール
試料溶液（4-Methylpentane-2-ol 添加）
標準溶液（1）
標準溶液（2）
標準溶液（3）
標準溶液（4）
SN比 9.3
uV
0
Ac
et
al
de
hy
de
M
et
ha
no
l
Ac
et
al
4-
M
et
hy
lp
en
ta
ne
-2
-o
l
Be
nz
en
e
Be
nz
en
e
0.0
2.5 5.0 7.5 10.0 12.5 15.0 17.5 min
9.5
10.0
10.5 11.0
min
Fig. 4 Chromatograms of Ethanol for disinfection, Sample Solution and Standard Solutions (1) – (4)
Ethanol for disinfection
Sample solution (spiked with 4-methylpentane-2-ol)
Standard solution (1)
Standard solution (2)
Standard solution (3)
Standard solution (4)
SN ratio 9.3
Sample name
Sample
Peak area of
methanol
Peak area of
acetaldehyde
Peak area of
acetal
Peak area of
benzene
A
E
C
E
B
E
Anhydrous ethanol
0
107
0
0
Ethanol for
disinfection
0
107
0
0
Diluted sample
name
Standard solution (1)
Standard solution (2)
Standard solution (3)
Standard solution (4)
Peak area of
methanol
Peak area of
acetaldehyde
Peak area
of acetal
Peak area of
benzene
A
T
C
T
B
T
Anhydrous ethanol
37050
1559
9418
1206
Ethanol for
disinfection
34838
3108
8863
1115
Sample name
Total amount of acetaldehyde and acetal
(vol ppm)
Amount of benzene
(vol ppm)
Anhydrous ethanol
0.73
0
Ethanol for
disinfection
0.36
0
Table 2 Average Areas and Amounts of Volatile Impurities (n=3)
Nexis is a trademark of Shimadzu Corporation in Japan and/or other countries.
Third-party trademarks and trade names may be used in this publication to refer to either the entities or their products/services.
Application
News
No.
G333
United States Pharmacopeia (USP) General Chapters
<611> ALCOHOL DETERMINATION stipulates two
analytical methods for quantitating ethanol: one with
distillation and the other by gas chromatography. The
latter (i.e. USP <611> Method II) further gives an
option of either using a packed column (Method II a)
or a capillary column (Method II b).
This article introduces a quantitative analysis of
ethanol in alcohol-based sanitizer gel according to
USP <611> Method II b.
N. Iwasa, T. Wada
Preparation of Standard Solution and Sample
Solution
5 mL each of 2 %(v/v) ethanol*1 and 2 %(v/v)
acetonitrile*1 (internal standard), both in water, were
pipetted into a 25 mL volumetric flask, made up to
volume with water and vortex to prepare a 0.4 %(v/v)
standard solution.
As a sample solution, a commercially available sanitizer
gel (ca. 80 %(v/v)) was first diluted with water to ca. 2
%(v/v) ethanol. To further bring down the concentration
to ca. 0.4 %(v/v), 5 mL of each of the prepared ca. 2
%(v/v) sample and 2 %(v/v) acetonitrile were aliquoted
into 25 mL volumetric flask and mixture was make up to
volume with water.
*1 USP<611> specifies the use of USP Alcohol Determination-Alcohol
RS (2 %(v/v) ethanol) and USP Alcohol Determination-Acetonitrile RS
(2 %(v/v) acetonitrile) to prepare the standard solution.
Analysis Conditions
Using the gas chromatograph Nexis™ GC-2030,
ethanol in the standard solution and the sample
solution
were
quantitated
according
to
USP<611>ALCOHOL DETERMINATION Method IIb. The
instrument configuration and analysis conditions for
the this experiment are listed below in Table 1.
Table 1 Instrument Configuration and Analysis Conditions
Fig. 2 Position and Quantity of Wool in the Insert
Gas Chromatography
Alcohol Determination of Sanitizer Gel
in accordance with USP<611>
Fig. 1 Sample Preparation Method
Model
: Nexis GC-2030 + AOC-20i Plus
Detector
: FID-2030 flame ionization detector
Column
: SH-Rtx™-624 (30 m
×0.53 mm I.D., d.f.= 3 µm)
Column Temperature
: 50 °C (5 min) – 10 °C/min – 200 °C (4 min)
Total 24 mins
Injection Temperature
: 210 °C
Injection Mode
: Split
Split Ratio
: 1: 5
Carrier Gas Controller
: Linear velocity (He)
Linear Velocity
: 34 cm/sec
Detector Temperature
: 280 °C
FID H
2 Flow Rate
: 32 mL/min
FID Make up Flow Rate : 24 mL/min (He)
FID Air Flow Rate
: 200 mL/min
Injection Volume
: 0.2 µL
Syringe
: Elastic Syringe, AOC (P/N: 221-49548)*2
<Standard solution>
2 %(v/v) ethanol
IS: 2 %(v/v) acetonitrile
Dilute each sample
5-fold
<Sample solution>
Sample: ca. 2 %(v/v) ethanol
IS: 2 %(v/v) acetonitrile
Dilute each
sample 5-fold
Sample: ca. 80 %(v/v) ethanol
Dilute the sample
40-fold
0.4 %(v/v) standard solution
ca. 0.4 %(v/v) sample solution
*2 When samples in aqueous solution are analyzed with a standard
syringe for AOC-20i Plus, the plunger motion may become dull
during analysis, which affects repeatability. Using an elastic
syringe for AOC (P/N: 221-49548) equipped with a plunger made
of titanium enables stable sample introduction.
In this analysis, a glass insert was specifically
configured as shown in Fig.2 to meet the requirements
for the system suitability test(SST) in USP<611>. 20 mg
of deactivated glass wool was packed into a split glass
insert at a position 20 mm from the top. Increasing the
amount of wool compared to the default amount of 10
mg and placing the wool slightly (i.e. 2 mm) above the
default position (i.e. 22 mm from the top) improved
reproducibility.
20 mg of glass wool
(P/N: 221-48600)
Insert for split injection
(P/N: 221-41444-84)
25 mL
＋
25 mL
＋
20 mm
95 mm
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No.
G333
Application
News
Shimadzu Corporation
For Research Use Only. Not for use in diagnostic procedure.
This publication may contain references to products that are not available in your country. Please contact us to check the availability of these
products in your country.
The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of Shimadzu.
Shimadzu disclaims any proprietary interest in trademarks and trade names used in this publication other than its own.
See http://www.shimadzu.com/about/trademarks/index.html for details.
The information contained herein is provided to you "as is" without warranty of any kind including without limitation warranties as to its
accuracy or completeness. Shimadzu does not assume any responsibility or liability for any damage, whether direct or indirect, relating to the
use of this publication. This publication is based upon the information available to Shimadzu on or before the date of publication, and subject
to change without notice.
© Shimadzu Corporation, 2020
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
min
Ethanol
Acetonitrile
（IS）
Chromatogram and Calibration Curve of the
Standard Solution
The chromatogram and calibration curve of the
standard solution are shown in Fig. 3 and 4. The SST
results of the standard solution are summarized in
Table 2.
The SST criteria include the following:
•
The resolution factor, R, between alcohol and the
internal standard be not less than 4.
•
The tailing factor of the alcohol peak be not
greater than 2.0.
•
Six replicate injections of the standard solution
show a relative standard deviation of not more
than 4.0 % in the ratio of the peak of alcohol to the
peak of the internal standard.
The results obtained with the standard solution
satisfied all three SST criteria. The requirement for
reproducibility (i.e. 4 %) was easily met with the RSD
of 0.4 %.
Chromatogram of Sample Solution and
Quantitative Result for Ethanol
The chromatogram of the sample solution is shown in
Fig. 5, and the quantitative results and repeatability
(n=3) are listed in Table 3.
Area ratio
Quantitative value (%)
Data 1
0.929279
78.997
Data 2
0.925411
78.668
Data 3
0.929298
78.998
Average
0.927996
78.888
%RSD
0.241
0.241
First Edition: Aug. 2020
Fig. 3 Chromatograms of Standard Solution
Fig. 4 Calibration Curve
Table 2 System Suitability of Standard Solution (n=6)
Compound
Peak
area
Area
ratio
Area
ratio %RSD
Symmetry
(tailing) factor
Resolution
(USP)
Ethanol
627440 0.941074
0.405
1.467
---
Acetonitrile (IS) 666723
---
1.255
10.265
10.265
In Table 2, the items specified in the system suitability test are
indicated in red.
Note: The values shown are reference values, not guaranteed values.
Fig. 5 Chromatograms of Sample Solution
Table 3 Ethanol Quantitative Values and Repeatability (n=3)
Note: The values shown are reference values and not intended to
be guaranteed values.
Conclusion
Alcohol concentration in sanitizer gel was determined
using a capillary column in compliance with USP
<611> Method IIb.
The SST was conducted with a standard solution and
satisfied with the resolution of 10.3 (cf. > 4 as a
requirement) between ethanol and acetonitrile, the
tailing factor of 1.5 (cf. < 2 as a requirement) and the
repeatability of 0.4 % RSD (cf. 4 % limit).
The repeatability remained well even with a sample
solution,
proving
the
robustness
of
the
gas
chromatograph Nexis GC-2030.
Nexis is a trademark of Shimadzu Corporation in Japan and/or other
countries.
Rtx is either a trademark or a registered trademark of Restek
Corporation in the United States and/or other countries.
Note: The experiment in this article was performed based on the
current version of USP-NF as of April 24, 2020.
0.0
0.1
0.2
0.3
Concentration
ratio
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
Area ratio
0.4
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
min
Ethanol
Acetonitrile
（IS）
No. SSI-GC-2005
■ Introduction
The current coronavirus pandemic has created an
unprecedented demand for alcohol-based hand
sanitizers. The US FDA has provided guidance to
allow manufacturing of hand sanitizers using ethanol
or isopropanol (IPA) as their active ingredient. The
United States Centers for Disease Control (CDC), the
World Health Organization (WHO), and the US
Pharmacopeia (USP) all have determined that ethanol
or IPA concentrations in hand sanitizers must be
between 60 and 95% to ensure germicidal and
viricidal properties.
We developed a GC FID method to accurately
quantify ethanol and IPA concentrations in two hand
sanitizer samples. By using nitrogen as the carrier
gas, this method is cost-effective and ensures the
product compliance with CDC and USP guidelines
and regulations.
■ Samples and Analytical Conditions/
Experimental
Ethanol (200 proof) and n-butanol (min. 99%) were
purchased from Sigma Aldrich. 2-propanol
(isopropanol or IPA, min. 99.9%) was purchased
from Fisher Scientific. The solutions and samples
were diluted in deionized water to specified
concentrations.
A Shimadzu GC-2030 chromatograph equipped with
split/splitless injector (SPL) and flame ionization
detector (FID) was used for this analysis and the data
were acquired, analyzed and reported using
LabSolutions LCGC software. The method
parameters are shown in table 1 below.
Table 1: Instrument Configuration and Analysis Conditions
GC system
Shimadzu GC-2030 with SPL, FID and AOC-20 Plus autosampler
Column
Rxi-624Sil MS, 30m x 0.32mm x 1.8µm
Injector Mode
Split at 1:20 ratio
Injection Volume
1.0 µL
Carrier Gas
Nitrogen (N2)
Flow mode
Constant linear velocity of 40cm/sec
Column Temperature
30°C, 4min – 30°C/min –120°C, 2min
Injection Port Temperature
250°C
FID Temperature and Gases
250°C, Hydrogen 32mL/min, Air 200mL/min, Makeup (N2) 24mL/min
Gas Chromatography
Determination of Ethanol and Isopropanol
Content in Hand Sanitizers Using Nitrogen
Carrier Gas
No. GC-2005
No. SSI-GC-2005
■ Results and Discussion
Calibration Curves
Since both ethanol and 2-propanol (isopropanol
alcohol or IPA) can be used to prepare hand
sanitizer, calibration standards were prepared with
both types of alcohol. An internal standard (IS) is
commonly used in these assays to improve accuracy.
Although acetonitrile is specified in the USP method
as the IS for ethanol, it elutes closer to IPA and may
cause column/liner deterioration with repeated
injections. In comparison, n-butanol elutes away
from both ethanol and IPA, and is not known to
cause degradation to the GC systems. It is commonly
used in blood alcohol content assays as an IS for
ethanol. Therefore, n-butanol was used as the IS in
this study.
Nitrogen (N2) was chosen as the carrier gas to reduce
the cost of analysis compared to using helium. As
shown in Figure 1, all peaks were well resolved, and
no contaminating peaks were found in water blank
with IS only.
The calibration standards were diluted to indicated
concentrations with 0.5% (v/v) of n-butanol in
deionized water. Internal standard quantification
methods were used, and the calibration curves were
fitted to linear regression without forcing through
zero.
Figure 1: Chromatograms of calibration standards and water blank with IS (n-butanol)
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
min
0
100000
200000
300000
400000
500000
600000
700000
800000
900000
1000000
1100000
1200000
1300000
1400000
1500000
1600000
1700000
1800000
1900000
2000000
2100000
2200000
2300000
uV
Ethanol
Isopropanol (IPA)
n-butanol (IS)
1% (v/v)
0.9% (v/v)
0.7% (v/v)
0.6% (v/v)
Blank
0.00
0.25
0.50
0.75
Conc. Ratio
0.00
0.25
0.50
0.75
1.00
1.25
Area Ratio
0.00
0.25
0.50
0.75
Conc. Ratio
0.00
0.25
0.50
0.75
1.00
1.25
1.50
Area Ratio
Ethanol
r2=0.99928
Figure 2: Four-point calibration curves for ethanol and IPA
Isopropanol (IPA)
r2=0.99998
No. SSI-GC-2005
Hand Sanitizer Samples
Two hand sanitizer samples were analyzed, one
containing ethanol and the other IPA. Each sample
was diluted 100-fold in IS solution for this analysis.
The concentration of alcohol content is calculated by
multiplying the concentration reported from the
software by 100.
Table 2: Concentration of alcohols in hand sanitizer samples.
Results are average of four injections. And the relative
standard deviation (RSD) for the repeated injections was also
shown for each sample.
Sample 1
Sample 2
Ethanol conc. (v/v)
59.11
not detected
IPA conc. (v/v)
not detected
56.40
RSD
2.677%
1.175%
Figure 3: Chromatograms of hand sanitizer samples and a blank injected after the samples. No carryover of analytes was observed
■ Conclusion
Alcohol content in two hand sanitizer samples was
successfully analyzed using Shimadzu GC-2030 on a
Rxi-624Sil MS column using N2 carrier gas. One of
the samples contains ethanol, while the other
contains isopropanol (IPA). The method used in this
study was modified from USP standard general
chapter 611, alcohol determination. The calibration
curves for both ethanol and IPA were linear with r2 >
0.999, and the analysis was straightforward with
very good repeatability (RSD < 3% for both samples).
Nitrogen was successfully used as the carrier gas in
this assay. Compared to helium, nitrogen is more
cost-effective. It is also more inert thus safer than
hydrogen, which is another commonly used cost-
saving alternative carrier gas. Taken together, both
ethanol and IPA content in hand sanitizers can be
easily determined using Shimadzu GC-2030 with SPL
and FID with nitrogen carrier gas.
■ Reference
1.
USP General Chapter 611, Alcohol Determination.
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
min
-100000
0
100000
200000
300000
400000
500000
600000
700000
800000
900000
1000000
1100000
1200000
1300000
1400000
1500000
1600000
1700000
1800000
1900000
2000000
2100000
2200000
2300000
2400000
uV
Hand sanitizer sample 1
Hand sanitizer sample 2
Blank (Internal standard only)
injected after samples
No. SSI-GC-2005
■ Consumables
Part Number
Description
Unit
Instrument
221-76650-01
Septa, Green, Premium Low Bleed
Pk of 25
GC-2030
227-35007-01
Split Liner with Wool
Pk of 5
221-75597-03
FID jet
221-81162-02
ClickTek Ferrule 0.5mm
Pk of 6
221-77155-41
ClickTek Column Connector
each
221-34618-00
Syringe, 10µL, fixed needle
each
AOC-20i/s
220-97331-31
Sample Vials, 1.5mL Amber Glass with Caps & Septa
Pk of 100
220-97331-47
Sample Vials, 1.5mL Amber Glass with Caps & Septa
Pk of 1000
220-97331-63
200µL Glass Silanized Inserts for 1.5mL Vials
Pk of 100
220-97331-23
Wash Vials, 4mL Amber Glass with Caps & Septa
Pk of 100
227-36077-01
SH-Rxi-624Sil MS Capillary Column, 0.32 x 1.8 x 30
each
Column
227-36078-01*
SH-Rxi-624Sil MS Capillary Column, 0.53 x 3 x 30
each
*Column conforms to USP general chapter 611 standard method
For Research Use Only. Not for use in diagnostic procedure.
This publication may contain references to products that are not available in your country. Please contact us to check the availability of
these products in your country.
The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of
Shimadzu. Shimadzu disclaims any proprietary interest in trademarks and trade names used in this publication other than its own.
See http://www.shimadzu.com/about/trademarks/index.html for details.
The information contained herein is provided to you "as is" without warranty of any kind including without limitation warranties as to its
accuracy or completeness. Shimadzu does not assume any responsibility or liability for any damage, whether direct or indirect, relating to
the use of this publication. This publication is based upon the information available to Shimadzu on or before the date of publication, and
subject
First Edition: August 2020
© Shimadzu Corporation, 2020
SHIMADZU SCIENTIFIC INSTRUMENTS
7102 Riverwood Drive, Columbia, MD 21046, USA
Phone: 800-477-1227/410-381-1227, Fax: 410-381-1222
URL: www.ssi.shimadzu.com
SHIMADZU Corporation
www.shimadzu.com/an/
Application
News
No.
A637
Introduction
The effects of alcohol-based hand sanitizers are dependent
on type of alcohol used and alcohol concentration. The
Center for Disease Control and Prevention (CDC) has
recommended sanitizers with 60 - 95% alcohol as the most
effective composition of hand sanitizers.
Ethanol, which has bactericidal activity, is prepared at the
optimal concentration level for a range of commercially
available alcohol-based sanitizers. To measure alcohol
concentration,
the
distillation
method
or
gas
chromatography (GC) is stipulated by the United States
Pharmacopeia (USP). These methods require more than 20
minutes per sample for analysis. Pretreatment, such as
dilution, is also required. In contrast, if the Fourier
transform infrared spectrophotometer (FTIR) is used, the
preparatory steps can be skipped and the ethanol content
in alcohol sanitizers can quickly be determined in
approximately one minute.
This report introduces a simple pass/fail judgment of
ethanol concentration in a commercially available ethanol
sanitizer using the photometric measurement function that
comes as standard in LabSolutions™ IR.
S. Iwasaki
Experimental
Dehydrated ethanol was spiked with water to prepare the
standards at concentrations of 70 vol% and 82 vol%. The
samples were measured using IRSpirit™, a Fourier transform
infrared
spectrophotometer, equipped
with QATR™-S
(diamond crystal), a single-reflection ATR accessory, as
shown in Fig. 1. The measurement conditions are shown in
Table 1. First, 20 to 30 µL of the sample amount was placed
onto the ATR crystal using a micropipette and, as shown in
Fig. 2, covered immediately with a volatile cover to
minimize evaporation, which could cause its concentration
to change. Fig. 3 shows the IR spectra of ethanol standards.
The figure shows that the heights of peaks from ethanol at
1086 cm-1 and 1044 cm-1 (green lines) and those from water
at 3340 cm-1 and 1650 cm-1 (blue lines) are dependent on
the concentration.
Table 1 Measurement Conditions
Fig. 3 IR Spectra of Ethanol Standards (70, 82 vol%)
Fourier Transform Infrared Spectrophotometer (FTIR)
Determination of Ethanol Content in and
Simple Fail/Pass Judgment of Alcohol Hand
Sanitizer by FTIR
Instrument
: IRSpirit, QATR-S (Diamond)
Resolution
: 4 cm-1
Accumulation
: 20
Apodization function
: Sqr-Triangle
Detector
: DLATGS
Fig. 1 IRSpirit™ FTIR with QATR™-S
Volatile
Cover
Fig. 2 QATR-S with Volatile Cover
― 70 vol%
― 82 vol%
1000
1500
2000
3000
4000
cm-1
0.0
0.1
0.2
0.3
0.4
0.5
Abs
1000
1050
1100
cm-1
0.0
0.1
0.2
0.3
0.4
0.5
Abs
www.shimadzu.com/an/
No.
A637
Application
News
Shimadzu Corporation
For Research Use Only. Not for use in diagnostic procedure.
This publication may contain references to products that are not available in your country. Please contact us to check the availability of these
products in your country.
The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of Shimadzu.
Shimadzu disclaims any proprietary interest in trademarks and trade names used in this publication other than its own.
See http://www.shimadzu.com/about/trademarks/index.html for details.
The information contained herein is provided to you "as is" without warranty of any kind including without limitation warranties as to its
accuracy or completeness. Shimadzu does not assume any responsibility or liability for any damage, whether direct or indirect, relating to the
use of this publication. This publication is based upon the information available to Shimadzu on or before the date of publication, and subject
to change without notice.
© Shimadzu Corporation, 2020
Pass/Fail Judgment Using Labsolutions IR
To maintain the quality of alcohol sanitizers, it is important to
control the concentrations of the constituents in these
sanitizers. As a general rule, the spectra of a sample of known
concentration and the sample to be controlled are analyzed to
estimate the concentration of the sample to be controlled
based on the height or area of the peak. Additionally, the
obtained concentration should be judged by the analyzer as
either pass or fail. These steps should be performed carefully
because they not only require a lot of time but may also be
affected by human error. The photometric measurement
function installed as standard on LabSolutions IR can
determine the absorbance or transmittance at specific wave
numbers/wavelengths, and calculate these results using the
formulas for pass/fail judgment. This makes it possible to
reduce the operation time significantly.
Using this function, we judged four commercially available
ethanol sanitizers (A – D) shown in Table 2. The samples
were analyzed without pretreatment and dilution.
The photometric measurement function screen is shown in
Fig. 4. The formula for pass/fail judgment is set up in
Equation tab (red box) as shown in Fig. 4. In this analysis, the
height from baseline to peak at 1044 cm-1 (C-O stretching
vibration) was used to calculate the ethanol concentration
(baseline drawn at 1110 cm-1 - 1020 cm-1). The formula for
pass/fail judgment was set up so that samples at 70 vol%
(height from baseline to peak: 0.301) - 82 vol% (height from
baseline to peak: 0.348) are judged Pass and the others are
judged Fail. After the measurement of sample spectra, the
data are automatically added to the sample table (blue box)
shown in Fig. 4 to judge the samples. As shown in Table 2,
Samples A and B, for which the concentrations were lower
than the set reference concentration, were judged Fail.
The measurement results of IR spectra (magnified view) are
shown in Fig. 5. Using the peak height from ethanol (black
line), the ethanol concentration can also be estimated.
Table 2 Labeling and Pass/Fail Judgment of Commercially
Available Ethanol Sanitizers
First Edition: Nov. 2020
Sample
Ethanol content labeled on
the product
Pass/fail judgment
A
58 vol%
Fail
B
65 vol%
Fail
C
70 vol%
Pass
D
76.9
～81.4 vol%
Pass
Fig. 4 Photometric Measurement Function Screen
Equation
Sample table
Conclusion
With IRSpirit and QATR-S, ethanol content in sanitizers could
be easily determined using just a single drop of sample.
Additionally, the ethanol content could be easily and
accurately judged for pass/fail by using the photometric
measurement function of LabSolutions IR software. The use
of this function can reduce the time required for analysis,
including judgment. Concerns over product fraud or fake
substances can be eliminated by controlling the quality of
the major active ingredient (ethanol) in sanitizers.
For an example of quantitative analysis using the program
installed as a standard function on LabSolutions IR, see also
Application News No. A630 “Quick and Easy Analysis of
Alcohol Content in Hand Sanitizer by FTIR Spectroscopy.”
1000
1025
1050
1075
1100
1125
cm-1
0.0
0.1
0.2
0.3
0.4
Abs
70 vol%
82 vol%
A
B
C
D
Fig.5 Measurement Results of IR Spectra (Magnified View)
LabSolutions, IRSpirit and QATR are trademarks of Shimadzu Corporation in Japan and/or other countries.
Application
News
No.
A626
Spectrophotometric Analysis
Measurement of Impurities in Ethanol
Using UV-Vis Spectrophotometer
At present, demand for ethanol for disinfection is increasing
sharply as preventive measure for an infectious disease.
When ethanol is to be used as a medical product,
identification testing and purity testing conforming to the
applicable Pharmacopoeias in each country are necessary.
Ultraviolet-visible (UV-Vis) spectrophotometry is used in
these tests as one technique for determining whether
impurities are present in ethanol.
In the experiment introduced here, measurement of “Other
impurities (absorbance)” in ethanols, which is described in
the Japanese Pharmacopoeia, European Pharmacopoeia, and
United States Pharmacopeia, was conducted using a
Shimadzu UV-1900i UV-Vis spectrophotometer, and
absorbance, which is specified as an acceptance standard in
the Pharmacopoeias, was judged automatically by using the
evaluation function of LabSolutions™ UV-Vis.
H. Abo
Test Method for Ethanols
The Japanese Pharmacopoeia (JP) describes the five items
“Clarity and color of solution,” “Acidity or alkalinity,” “Volatile
impurities,” “Other impurities (absorbance),” and “Residue on
evaporation” under “Purity” testing of ethanol, anhydrous
ethanol and ethanol for disinfection. Among these, “Other
impurities (absorbance)” is measured in order to determine
the presence/absence of impurities contained in ethanol
based on absorption in the ultraviolet (UV) region.
The European Pharmacopoeia (EP) includes “Absorbance” as
one item in “TESTS” and describes similar testing using UV-Vis
spectrophotometry.
The United States Pharmacopeia (USP) specifies
“ULTRAVIOLET ABSORPTION” in “SPECIFIC TESTS” and also
describes testing by UV-Vis spectrophotometry.
The measurement method for “Other impurities” is the same
in the three Pharmacopoeias. The absorption spectrum of the
sample is measured using a cell with an optical path length
of 5 cm and water as a blank, and judgment of acceptability
is based on absorbance.
Specifically, the Pharmacopoeias provide that the absorbances
at 240 nm, between 250 and 260 nm, and between 270 and
340 nm are not more than 0.40, 0.30, and 0.10, respectively,
when the absorption spectrum is measured in the 235 to
340 nm wavelength region. The provision also specify that the
absorption spectrum should be smooth and “show a steadily
descending curve with no observable peaks or shoulders.”
Measurement of Anhydrous Ethanol
Anhydrous ethanol was measured with the UV-1900i UV-Vis
spectrophotometer shown in Fig. 1, using a Shimadzu square
long-path absorption cell holder and a 50 mm square cell.
Table 1 shows the measurement conditions.
Fig. 2 shows the results of spectrum measurement.
Fig. 1 UV-1900i UV-Vis Spectrophotometer
Table 1 Measurement Conditions
Instrument :
UV-1900i
Software :
LabSolutions
UV-Vis
Measurement wavelength range : 235 - 340 nm
Scan speed
: Medium
Sampling pitch
: 0.5 nm
Slit width
: 1 nm (fixed)
Fig. 2 Result of Measurement of Anhydrous Ethanol
In Fig. 2, it can be confirmed that absorbance is not more than
0.40 at 240 nm, not more than 0.30 between 250 and 260 nm,
and not more than 0.10 between 270 and 340 nm, and there
are no clear peaks or remarkable shoulders in the absorption
spectrum curve.
Wavelength (nm)
A
b
so
rban
ce
(A
bs
.)
First Edition: Jul. 2020
For Research Use Only. Not for use in diagnostic procedure.
This publication may contain references to products that are not available in your country. Please contact us to check the availability of these
products in your country.
The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of Shimadzu.
Shimadzu disclaims any proprietary interest in trademarks and trade names used in this publication other than its own.
See http://www.shimadzu.com/about/trademarks/index.html for details.
The information contained herein is provided to you "as is" without warranty of any kind including without limitation warranties as to its
accuracy or completeness. Shimadzu does not assume any responsibility or liability for any damage, whether direct or indirect, relating to the
use of this publication. This publication is based upon the information available to Shimadzu on or before the date of publication, and subject
to change without notice.
© Shimadzu Corporation, 2020
www.shimadzu.com/an/
Application
News
No.
A626
Pass/Fail Judgment Using LabSolutions UV-Vis
The provisions for “Other impurities (absorbance)” of anhydrous
ethanol specify that the absorbances at 240 nm, between 250
and 260 nm, and between 270 and 340 nm are not more than
0.40, 0.30, and 0.10, respectively. However, reading the
absorbances of all the measured samples is time-consuming
work and judgments must be made carefully, as human error is
also possible. The time required for this work can be reduced by
the spectral evaluation function of LabSolutions UV-Vis.
The spectral evaluation function features 8 pass/fail criteria
and 33 standard evaluation methods, including point pick,
maximum value, minimum value, peak, valley, area, statistics,
and cutoff, as well as a pass/fail judgment function. Here, a
pass/fail judgment for anhydrous ethanol was made using
the pass/fail judgment function.
Setting of Pass/Fail Judgment Using
LabSolutions UV-Vis
Although there are three judgment conditions by absorbance,
in analysis of anhydrous ethanol, judgments are made by using
[Point Pick – Single Point] and [Maximum Value – Single Point].
[Point Pick – Single Point] reads the absorbance of a fixed
wavelength, and [Maximum Value – Single Point] can read the
maximum value in a predetermined wavelength range.
First, absorbance of NMT 0.40 (“not more than 0.40”) at
240 nm is set. Fig. 3 shows the Detailed Settings screen for
evaluation of [Point pick – Single point]. The setting is made
from this screen. The wavelength is set at 240 nm, and the
pass/fail judgment criterion is set at NMT 0.40.
Fig. 3 Detailed Settings Screen for
[Point Pick – Single Point] Evaluation
Next, the remaining conditions are set. Fig. 4 shows the
Detailed Settings screen for evaluation of [Maximum Value –
Single Point]. The wavelength range is designated, and the
maximum value of absorbance in that range is read.
Here, two conditions are set. The judgment criteria of NMT
0.30 is set for 250-260 nm, and NMT 0.10 is set for 270-340 nm.
Fig. 4 Detailed Settings Screen for
[Maximum Value – Single Point] Evaluation
Results of Pass/Fail Judgment
Fig. 5 shows the results of the pass/fail judgments for the
anhydrous ethanol shown in Fig. 2 and a simulated rejected
sample. The absorbance values of the anhydrous ethanol are
within the pass range for all three wavelength conditions. On
the other hand, in case of failure, the result can be
understood at a glance, as the evaluation line is colored red.
Fig. 6 shows an enlarged view of the evaluation table.
In pass/fail judgments, the data are added to the evaluation
table automatically after spectrum acquisition. Therefore, the
judgment can be completed simply by measuring the sample.
Fig. 5 Results of Pass/Fail Judgment
Conclusion
In this experiment, measurements of anhydrous ethanol were
conducted in accordance with the Japanese Pharmacopoeia,
European Pharmacopoeia, and United States Pharmacopeia
using a UV-1900i, and a pass/fail judgment was made using the
spectral evaluation function of the LabSolutions UV-Vis
software. Analysis time, including judgment work, can be
substantially reduced by using the spectral evaluation function.
Fig. 6 Enlargement of Evaluation Table
LabSolutions is a trademark of Shimadzu Corporation in Japan and/or other countries.
- : Anhydrous ethanol
- : Simulated rejected sample
Hand Sanitizer Analysis Application Notebook
▶
This brochure may contain references to products that are not available in your country. Please contact us to check the availability of these
products in your country.
Company names, product/service names and logos used in this publication are trademarks and trade names of Shimadzu Corporation or its
affiliates, whether or not they are used with trademark symbol “TM” or “®”.
Third-party trademarks and trade names may be used in this publication to refer to either the entities or their products/services. Shimadzu
disclaims any proprietary interest in trademarks and trade names other than its own.
The contents of this publication are provided to you “as is” without warranty of any kind, and are subject to change without notice. Shimadzu
does not assume any responsibility or liability for any damage, whether direct or indirect, relating to the use of this publication.
Shimadzu Corporation
www.shimadzu.com/an/
Shimadzu Scientific Instruments
7102 Riverwood Drive, Columbia, Maryland 21046, U.S.A.
Phone: 800-477-1227/410-381-1227, Fax: 410-381-1222
www.ssi.shimadzu.com
© Shimadzu Corporation 2020
December 2020
