Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини
Organic acids are a large group of biologically active compounds that perform important functions in the plant organism. Moreover, all plants, regardless of the species and family, contain organic acids to a small or large extent as organic acids belong to intermediate metabolites arising from the...
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| Published in: | Журнал органічної та фармацевтичної хімії |
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| Date: | 2021 |
| Volume: | 19 |
| Issue: | 1(73) |
| Pages: | 53-58 |
| ISSN: | 2518-1548 |
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| Language: | English |
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2021
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| author | Maslov, O. Yu. Kolisnyk, S. V. Kostina, T. A. Shovkova, Z. V. Ahmedov, E. Yu. Komisarenko, M. A. |
| author_facet | Maslov, O. Yu. Kolisnyk, S. V. Kostina, T. A. Shovkova, Z. V. Ahmedov, E. Yu. Komisarenko, M. A. |
| author_institution_txt_mv | [
{
"author": "O. Yu. Maslov",
"institution": "National University of Pharmacy",
"orcid": ""
},
{
"author": "S. V. Kolisnyk",
"institution": "National University of Pharmacy",
"orcid": ""
},
{
"author": "T. A. Kostina",
"institution": "National University of Pharmacy",
"orcid": "0000-0001-5048-8575"
},
{
"author": "Z. V. Shovkova",
"institution": "National University of Pharmacy",
"orcid": "0000-0003-1908-1237"
},
{
"author": "E. Yu. Ahmedov",
"institution": "National University of Pharmacy",
"orcid": ""
},
{
"author": "M. A. Komisarenko",
"institution": "National University of Pharmacy",
"orcid": "0000-0002-1161-8151"
}
] |
| author_orcid_str_mv | 0000-0001-5048-8575 0000-0003-1908-1237 0000-0002-1161-8151 |
| author_sort | Maslov, O. Yu. |
| baseUrl_str | https://ophcj.nuph.edu.ua/oai |
| collection | OJS |
| container_end_page | 58 |
| container_issue | 1(73) |
| container_start_page | 53 |
| container_title | Журнал органічної та фармацевтичної хімії |
| container_volume | 19 |
| datestamp_date | 2026-08-24T15:33:48Z |
| description | Organic acids are a large group of biologically active compounds that perform important functions in the plant organism. Moreover, all plants, regardless of the species and family, contain organic acids to a small or large extent as organic acids belong to intermediate metabolites arising from the oxidation of proteins and amino acids, fats and carbohydrates.Aim. To validate the method of alkalimetry proposed with potentiometric detection of the end-point for the quantitative determination of free organic acids in raspberry leaves.Results and discussion. The method proposed was validated according to the International Conference on Harmonization (ICH) guidelines. The linearity was in the concentration range of 40 – 200 % (r2 = 0.9991). The percentage of recovery was found to be in the range of 98.77 – 102.48 %. The repeatability and intermediate precision were 1.58 % and 1.74 %, respectively. The method is accurate and reliable, with the relative standard deviation of less than 2 %.Experimental part. Leaves of raspberry were collected in the Kharkiv region during the period of full ripening. A Hanna 2550 pH-meter with a HI 1131P potentiometric electrode was used for alkalimetric titration of free organic acids. The titration was carried out using a microburette with Class A accuracy.Conclusions. The alkalimetry method for the quantitative determination of free organic acids in raspberry leaves has been proposed and validated according to the following parameters: specifcity, linearity, accuracy, repeatability, intermediate precision, robustness. It has been confrmed that the method is simple, reliable, accurate and cost-effective.Key words: raspberry; leaves; free organic acids; alkalimetry; validation |
| doi_str_mv | 10.24959/ophcj.21.226278 |
| first_indexed | 2025-07-17T13:00:59Z |
| format | Article |
| fulltext |
Журнал органічної та фармацевтичної хімії. – 2021. – Т. 19, вип. 1 (73)
53
ISSN 2518-1548 (Online) ISSN 2308-8303 (Print)
UDC 543.554.4:54.062:615.3:582.711.712 https://doi.org/10.24959/ophcj.21.226278
O. Yu. Maslov, S. V. Kolisnyk, T. A. Kostina, Z. V. Shovkova,
E. Yu. Ahmedov, M. A. Komisarenko
National University of Pharmacy of the Ministry of Health of Ukraine, Ukraine
53, Pushkins’ka str., Kharkiv, 61002. E-mail: alexmaslov392@gmail.com
Validation of the alkalimetry method for the quantitative
determination of free organic acids in raspberry leaves
Organic acids are a large group of biologically active compounds that perform important functions in the plant
organism. Moreover, all plants, regardless of the species and family, contain organic acids to a small or large ex-
tent as organic acids belong to intermediate metabolites arising from the oxidation of proteins and amino acids,
fats and carbohydrates.
Aim. To validate the method of alkalimetry proposed with potentiometric detection of the end-point for the quan-
titative determination of free organic acids in raspberry leaves.
Results and discussion. The method proposed was validated according to the International Conference on
Harmonization (ICH) guidelines. The linearity was in the concentration range of 40 – 200 % (r2 = 0.9991). The percentage
of recovery was found to be in the range of 98.77 – 102.48 %. The repeatability and intermediate precision were 1.58 %
and 1.74 %, respectively. The method is accurate and reliable, with the relative standard deviation of less than 2 %.
Experimental part. Leaves of raspberry were collected in the Kharkiv region during the period of full ripening.
A Hanna 2550 pH-meter with a HI 1131P potentiometric electrode was used for alkalimetric titration of free organic
acids. The titration was carried out using a microburette with Class A accuracy.
Conclusions. The alkalimetry method for the quantitative determination of free organic acids in raspberry
leaves has been proposed and validated according to the following parameters: specificity, linearity, accuracy,
repeatability, intermediate precision, robustness. It has been confirmed that the method is simple, reliable, ac-
curate and cost-effective.
Key words: raspberry; leaves; free organic acids; alkalimetry; validation
О. Ю. Маслов, С. В. Колісник, Т. А. Костіна, З. В. Шовкова, Е. Ю. Ахмедов,
М. А. Комісаренко
Національний фармацевтичний університет Міністерства охорони здоров’я України, Україна
Валідація алкаліметричної методики кількісного визначення вільних органічних
кислот у листі малини
Органічні кислоти – велика група біологічно активних сполук, які виконують важливі функції в обміні
речовин рослин. Усі рослини, незалежно від виду та родини, містять органічні кислоти в невеликій або значній
кількості, бо ці речовини належать до проміжних метаболітів, що утворюються в результаті окиснення біл-
ків, амінокислот, жирів та вуглеводів.
Мета. Валідувати запропоновану алкаліметричну методику з потенціометричним виявленням кінцевої
точки титрування для кількісного визначення вільних органічних кислот у листі малини.
Результати та їх обговорення. Запропонований метод валідовано згідно з директивою International
Conference on Harmonization. Лінійність зберігалася в діапазоні концентрацій 40 – 200 % (r2 = 0,9991). Визначено,
що відсоток відновлення становить 98,77 – 102,48 %, повторюваність та проміжна точність – 1,58 % та 1,74 %
відповідно. Метод характеризується як точний і надійний, має відносне стандартне відхилення менше 2 %.
Експериментальна частина. Листя малини в період повного дозрівання збирали в Харківській об-
ласті. Для алкаліметричного титрування вільних органічних кислот використовували рН-метр Hanna 2550
з потенціометричним електродом HI 1131P. Титрування проводили мікробюреткою з класом точності А.
Висновки. Розроблену титриметричну методику кількісного визначення вільних органічних кислот
у листі малини валідовано за такими параметрами: специфічність, лінійність, точність, збіжність, внутрішня
прецизійність, робасність. Підтверджено, що метод є простим, надійним, точним та економічно вигідним.
Ключові слова: малина; листя; вільні органічні кислоти; алкаліметрія; валідація
Copyright © 2021, O. Yu. Maslov, S. V. Kolisnyk, T. A. Kostina, Z. V. Shovkova, E. Yu. Ahmedov
This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0)
A variety of biologically active compounds have
been found in raspberry leaves, including flavonoids,
phenolic acids, organic acids, ellagitannins, gallotan-
nins and proanthocyanidins [1, 2]. There is a rather
high interest in determining the amount of organic
acids in raspberry leaves in literary sources [3, 4].
According to these studies, the total amount of orga-
nic acids is relatively high and ranges from 1.1 to 2.3 %;
it makes raspberry leaves a promising raw material
of organic acids [5, 6].
Organic acids are a group of biologically active
compounds with a wide spectrum of the pharmaco-
logical activity. They reveal vitamin properties, pos-
sess the choleretic effect, and normalize the activity of
the digestive system. Organic acids regulate the sec-
retion of the bile and pancreatic juice, improve appe-
tite, possess bactericidal properties and reduce pu-
trefactive processes in the body [7].
Nowadays there are various analytical methods
for determining organic acids such as titration, ion
chromatography [8], high-performance liquid chro-
matography-ultraviolet detection (HPLC-UV) [9], ca-
pillary electrophoresis [10], gas chromatography (GC)
[11] and thin-layer chromatography [12].
Journal of Organic and Pharmaceutical Chemistry. – 2021. – Vol. 19, Iss. 1 (73)
54
ISSN 2308-8303 (Print) ISSN 2518-1548 (Online)
Although HPLC-UV and GC have been proposed for
the determination of organic acids before, they re-
quire high skillful analysts and expensive instruments.
In addition, most of the procedures previously descri-
bed require expensive instrumental setup. That is why
in the current work the method of alkalimetry with
potentiometric detection of the end-point was cho-
sen for determining organic acids in raspberry leaves
as it is simple, reliable, rapid and economical. Thus,
the aim of the study was to validate the method pro-
posed for the quantitative determination of free or-
ganic acids in raspberry leaves.
Experimental part
The study object was raspberry leaves collected
in the Kharkiv region during the period of full ripe-
ning, according to the rules of harvesting this type
of plant. Drying of leaves was carried out at a tem-
perature of 60 °C to a residual humidity of not more
than 20 %. A Hanna 2550 pH meter with HI 1131Р
potentiometric electrode was used in the study. All tit-
rations were carried out manually. Free organic acids
were titrated using a microburette with Class A accu-
racy. Weighing was carried out using an АN100 digital
analytical balance (AXIS, Ukraine) with d = 0.0001 g.
Citric acid was purchased from Sigma Aldrich
(≥ 98 %), NaOH was of analytical grade. In order to
prepare NaOH solution with the concentration of 0.05 M,
1.0 g of NaOH was dissolved in distilled water. The so-
lution was diluted to 250 mL with the same water
and standardized.
The procedure of the quantitative determina-
tion of free organic acids in raspberry leaves. Place
2.0 g (accurate weight) of the crushed raw material
in a 100 mL flask with a ground glass joint, then pour
40 mL of distilled water in the flask, equip it with
a condenser and keep the flask for 2 h on a boiling
water bath. After cooling quantitatively transfer the so-
lution into a 50 mL volumetric flask and dilute to the vo-
lume (solution A).
Place 5.00 mL of the solution A in a 100 mL flask,
and add 45.0 mL of distilled water with the subse-
quent titration of the solution by 0.05 M sodium hy-
droxide. After adding each portion of 0.05 M sodium
hydroxide mix the solution thoroughly, and record
the electrode potential.
The blank experiment was also performed. Accor-
ding to it, the blank volume of 0.05 M sodium hydro-
xide was 0.03 mL.
The content of organic acids in the solution was
calculated from the value of the equivalent volume
of the titrant. The equivalent volume of the titrant
was determined by a differential curve constructed
in the ∆E/ΔV – V coordinates. The equivalence point
was fixed at the maximum of the differential curve.
The perpendicular line was dropped to the horizon-
tal axis (the volume of the titrant) through the maxi-
mum, and the volume of the titrant spent on titra-
tion was determined (Fig. 1).
The content of free organic acids (X, %) with refe-
rence to citric acid in the completely dry raw mate-
rial was calculated by the following formula:
X ,=
( )·0.0032·50·100·100·K
m·5·(100 W )
V – V
–
eq x
where: 0.0032 – is the amount of citric acid equivalent
to 1 mL of sodium hydroxide solution (0.05 mol/L), g;
Veq – is the volume of sodium hydroxide solution
(0.05 mol/L) used for titration, mL; Vx – is volume of
sodium hydroxide solution (0.05 mol/L) spent for ti-
tration in the blank experiment, mL; m – is the mass
of the raw material used, g; K – is the correction co-
efficient for 0.05 mol/L sodium hydroxide solution;
W – is the loss on drying of the raw material, %.
V eq.
0.00 0.05 0.10 0.15 0.20 0.25 0.30
Volume of titrant, mL
0.35 0.40 0.45 0.50 0.55 0.60 0.65 0.70 0.75 0.80
0
25
Δ
Δ
E
/
V
50
75
100
125
150
175
200
225
250
Fig. 1. The potentiometric titration curve of determination total free organic acids in raspberry leaves
Журнал органічної та фармацевтичної хімії. – 2021. – Т. 19, вип. 1 (73)
55
ISSN 2518-1548 (Online) ISSN 2308-8303 (Print)
Validation
Validation of the alkalimetric method for the quan-
titative determination of the amount of free organic
acids in raspberry leaves by potentiometric titration
was performed according to the International Confe-
rence on Harmonization (ICH). The titrimetric method
proposed was validated by the following parameters:
specificity, accuracy, linearity, repeatability, interme-
diate precision, robustness.
The specificity of the method was studied by po-
tentiometric titration of the solvent.
The accuracy was verified by the method of addi-
tives in a triplicate analysis of three levels of concen-
tration of organic acids corresponding to 40, 60, 80 %
of the working concentrations of organic acids. The stan-
dard solution of citric acid was prepared as follows:
0.076 g (accurate weight) of citric acid was placed in
a 200.00 mL volumetric flask, and the solution was
diluted to the volume with distilled water. Then an ali-
quot of the resulting standard solution of 2.00, 3.00,
4.00 mL was taken and placed in a 100.0 mL flask.
After that 5.00 mL of the extract obtained from rasp-
berry leaves was added to the flask, then 45.0 mL of
distilled water was added, and the solution was titra-
ted. The evaluation criterion in determining the accu-
racy was the value of the relative standard deviation
(RSD), which according to the requirements should
be not more than 2 %, and the percentage of recovery
should be from 95 to 105 %.
The linearity of the method was studied at 9 concen-
tration levels (40, 60, 80, 100, 120, 140, 160, 180, 200 %)
of the theoretical content of the total amount of free
organic acids (calculated with reference to citric acid, %)
in raspberry leaves. In order to evaluate linearity of
the method, different aliquots of the extract were taken
(2.00; 3.00; 4.00; 5.00; 6.00; 7.00; 8.00; 9.00; 10.00 mL).
After that each aliquot was placed in a 100.0 mL flask
and diluted to the volume with distilled water. The quan-
titative content of the total amount of free organic
acids (calculated with reference to citric acid, %) in
raspberry leaves in the solutions obtained was then
determined according to the alkalimetry method of
titration. The linearity was assessed by a linear rela-
tionship between the concentration of the total amount
of free organic acids and the equivalent volume of
the titrant, as well as the correlation coefficient calcu-
lated. The linear regression was calculated by the me-
thod of least squares to obtain the regression equa-
tion and determine the correlation coefficient (r2).
According to the requirements of ICH, the value of
the correlation coefficient when studying the linea-
rity of the analytical method for determining the quan-
titative content of the active substance should be ≥ 0.999.
The repeatability of the method was checked by
preparing an aqueous extract of raspberry leaves from
6 portions of the raw material within a short period of
time using the same set of reagents and with the par-
ticipation of the same analyst. The intermediate pre-
cision was determined as described above in the same
laboratory, but in different days. The acceptance crite-
rion is expressed by the value of the relative standard
deviation, which should not exceed 2 %.
The robustness of the potentiometric procedure
was tested at 100 % concentration of free organic
acids with the participation of two different analysts
and two different burettes. The acceptance criterion
is expressed by the value of the relative standard de-
viation, which should not exceed 2 %.
The statistical processing of experimental data ob-
tained was performed in accordance with the mono-
graph «Statistical analysis of the results of a chemical
experiment» of the State Pharmacopeia of Ukraine.
Results and discussion
When studying the specificity of the method, it was
shown that the solvent used in the samples prepara-
tion and the probable impurities did not affect the re-
sult of the quantification of the amount of free or-
ganic acids in raspberry leaves (Table 1).
Linearity was proven in the concentration range
from 40 % to 200 %. A calibration curve of the de-
pendence of the equivalent volume of the titrant
values on the volume of aliquots of the extract from
raspberry leaves was plotted (Fig. 2). The regres-
sion equation of the curve had the following form:
y = 0.1667x – 0.2722. The value of the correlation
coefficient (r2) was equal to 0.9991 (Fig. 2).
When testing the method for the quantitative de-
termination of the amount of free organic acids by li-
nearity parameters it was found that the correlation
coefficient (r2) was 0.9991. Therefore, there is a di-
rect linear relation between the equivalent volume
of the titrant and the concentration of organic acids.
Table 1
The results of the titration to prove the specificity
of the method developed (n = 3, P = 95 %)
Vtitrant, mL Content of organic
acids, % Statistical analysis
Blank experiment (titration of distilled water)
0.03 0.05
0.045 ± 0.02 %
sx = 0.00140.02 0.035
0.03 0.05
Results of titration of the extract from raspberry leaves
0.57 1.00
1.00 ± 0.02 %
sx = 0.00330.56 0.99
0.57 1.00
Journal of Organic and Pharmaceutical Chemistry. – 2021. – Vol. 19, Iss. 1 (73)
56
ISSN 2308-8303 (Print) ISSN 2518-1548 (Online)
The accuracy of the method was assessed using
the percentage of recovery and the relative standard
deviation. The percentage of recovery was found to
be in the range from 98.77 to 102.48 %, and its ave-
rage value was 100.45 %, the value of the relative
standard deviation when assessing the correctness
of the method was 1.45 % and did not exceed 2 %
(Table 2).
The precision of the method was confirmed by
repeatability and intermediate precision. The values
of RSD for repeatability and intermediate precision
were 1.58 and 1.74 %, respectively. The RSD values
were less than 2 %. It proves that the method is pre-
cise (Tables 3, 4).
The robustness of the method was determined
by changing the analyst and burette. It was found that
the RSD values of inter-analyst and inter-burette were
Fig. 2. The calibration curve of the titrant volume vs the volume of an aliquot of the extract prepared
Table 2
Recovery studies by the procedure of standard additions
The amount
present, g
The amount of citric acid
added, g
The amount of organic
acids taken, g
The amount
recovered, g Recovery, % SD, % RSD, %
0.019 0.0052 0.0242
0.024 99.17
1.46 1.45
0.0248 102.48
0.0246 101.65
0.019 0.0134 0.0324
0.032 98.77
0.033 101.85
0.0326 100.62
0.019 0.0184 0.0374
0.037 98.93
0.0372 99.47
0.0378 101.07
Table 3
Repeatability of organic acids in raspberry leaves
Number of samples Content of free
organic acids, %
1 0.95
2 0.97
3 0.93
4 0.95
5 0.95
6 0.95
Mean, % 0.95
SD 0.0151
Confidence interval (P = 95 %), % 0.0120
RSD, % 1.58
Журнал органічної та фармацевтичної хімії. – 2021. – Т. 19, вип. 1 (73)
57
ISSN 2518-1548 (Online) ISSN 2308-8303 (Print)
1.52 and 1.37 %, respectively. The RSD values were
less than 2 %, showing that minor changes in condi-
tions have little effect on the results (Table 5).
Conclusions
The alkalimetric method for the quantitative de-
termination of free organic acids in the raspberry
leaves has been developed and validated according
to the following parameters: specificity, linearity, ac-
curacy, repeatability, intermediate precision, robust-
ness. It has been confirmed that the method is simple,
reliable, accurate and cost-effective.
Conflict of Interests: the authors have no con-
flict of interests to declare.
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Table 4
Intermediate precision of organic acids in raspberry leaves
Number of samples
Content of free organic acids, %
The first day The second day
1 0.95 0.93
2 0.95 0.93
3 0.93 0.95
4 0.97 0.97
5 0.93 0.95
6 0.95 0.97
Mean, % 0.95 0.95
SD 0.0151 0.0179
Confidence interval (P = 95 %), % 0.0120 0.0143
Mean, % 1.59 1.88
Mean RSD, % 1.74
Table 5
Robustness of organic acids in raspberry leaves
Concentration of
organic acids, %
Content of free organic acids, % RSD, %
The first analyst The second
analyst The first burette The second
burette Inter-analysts Inter-burettes
0.95 0.95 0.95 0.97 0.93
1.52 1.37
0.95 0.95 0.95 0.97 0.95
0.95 0.97 0.93 0.97 0.97
0.95 0.97 0.93 0.95 0.93
0.95 0.93 0.93 0.95 0.95
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Journal of Organic and Pharmaceutical Chemistry. – 2021. – Vol. 19, Iss. 1 (73)
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ISSN 2308-8303 (Print) ISSN 2518-1548 (Online)
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Accepted: 23. 01. 2021
Стаття є фрагментом комплексних наукових робіт Національного фармацевтичного університету за темою «Фармакогностичне
дослідження лікарської рослинної сировини та розробка фітотерапевтичних засобів на її основі» (№ держреєстрації 0114U000946).
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| id | oai:ojs.journals.uran.ua:article-226278 |
| institution | Journal of Organic and Pharmaceutical Chemistry |
| issn | 2518-1548 |
| keywords_txt_mv | |
| language | English |
| last_indexed | 2026-08-25T01:02:11Z |
| publishDate | 2021 |
| publisher | National University of Pharmacy |
| record_format | ojs |
| resource_txt_mv | ophcjnupheduua/1d/157e8ee18f33e378488592c43fac2d1d.pdf |
| spelling | oai:ojs.journals.uran.ua:article-2262782026-08-24T15:33:48Z Validation of the alkalimetry method for the quantitative determination of free organic acids in raspberry leaves Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини Maslov, O. Yu. Kolisnyk, S. V. Kostina, T. A. Shovkova, Z. V. Ahmedov, E. Yu. Komisarenko, M. A. малина; листя; вільні органічні кислоти; алкаліметрія; валідація raspberry; leaves; free organic acids; alkalimetry; validation Organic acids are a large group of biologically active compounds that perform important functions in the plant organism. Moreover, all plants, regardless of the species and family, contain organic acids to a small or large extent as organic acids belong to intermediate metabolites arising from the oxidation of proteins and amino acids, fats and carbohydrates.Aim. To validate the method of alkalimetry proposed with potentiometric detection of the end-point for the quantitative determination of free organic acids in raspberry leaves.Results and discussion. The method proposed was validated according to the International Conference on Harmonization (ICH) guidelines. The linearity was in the concentration range of 40 – 200 % (r2 = 0.9991). The percentage of recovery was found to be in the range of 98.77 – 102.48 %. The repeatability and intermediate precision were 1.58 % and 1.74 %, respectively. The method is accurate and reliable, with the relative standard deviation of less than 2 %.Experimental part. Leaves of raspberry were collected in the Kharkiv region during the period of full ripening. A Hanna 2550 pH-meter with a HI 1131P potentiometric electrode was used for alkalimetric titration of free organic acids. The titration was carried out using a microburette with Class A accuracy.Conclusions. The alkalimetry method for the quantitative determination of free organic acids in raspberry leaves has been proposed and validated according to the following parameters: specifcity, linearity, accuracy, repeatability, intermediate precision, robustness. It has been confrmed that the method is simple, reliable, accurate and cost-effective.Key words: raspberry; leaves; free organic acids; alkalimetry; validation Органічні кислоти – велика група біологічно активних сполук, які виконують важливі функції в обміні речовин рослин. Усі рослини, незалежно від виду та родини, містять органічні кислоти в невеликій або значній кількості, бо ці речовини належать до проміжних метаболітів, що утворюються в результаті окиснення білків, амінокислот, жирів та вуглеводів.Мета. Валідувати запропоновану алкаліметричну методику з потенціометричним виявленням кінцевої точки титрування для кількісного визначення вільних органічних кислот у листі малини.Результати та їх обговорення. Запропонований метод валідовано згідно з директивою International Conference on Harmonization. Лінійність зберігалася в діапазоні концентрацій 40 – 200 % (r2= 0,9991). Визначено, що відсоток відновлення становить 98,77 – 102,48 %, повторюваність та проміжна точність – 1,58 % та 1,74 % відповідно. Метод характеризується як точний і надійний, має відносне стандартне відхилення менше 2 %.Експериментальна частина. Листя малини в період повного дозрівання збирали в Харківській області. Для алкаліметричного титрування вільних органічних кислот використовували рН-метр Hanna 2550 з потенціометричним електродом HI 1131P. Титрування проводили мікробюреткою з класом точності А.Висновки. Розроблену титриметричну методику кількісного визначення вільних органічних кислоту листі малини валідовано за такими параметрами: специфічність, лінійність, точність, збіжність, внутрішня прецизійність, робасність. Підтверджено, що метод є простим, надійним, точним та економічно вигідним.Ключові слова: малина; листя; вільні органічні кислоти; алкаліметрія; валідація National University of Pharmacy 2021-03-15 Article Article application/pdf https://ophcj.nuph.edu.ua/article/view/226278 10.24959/ophcj.21.226278 Journal of Organic and Pharmaceutical Chemistry; Vol. 19 No. 1(73) (2021); 53-58 Журнал органической и фармацевтической химии; Том 19 № 1(73) (2021); 53-58 Журнал органічної та фармацевтичної хімії; Том 19 № 1(73) (2021); 53-58 2518-1548 2308-8303 en https://ophcj.nuph.edu.ua/article/view/226278/226704 Copyright (c) 2021 O. Yu. Maslov, S. V. Kolisnyk, T. A. Kostina, Z. V. Shovkova, E. Yu. Ahmedov, M. A. Komisarenko http://creativecommons.org/licenses/by/4.0 |
| spellingShingle | малина листя вільні органічні кислоти алкаліметрія валідація Maslov, O. Yu. Kolisnyk, S. V. Kostina, T. A. Shovkova, Z. V. Ahmedov, E. Yu. Komisarenko, M. A. Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини |
| title | Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини |
| title_alt | Validation of the alkalimetry method for the quantitative determination of free organic acids in raspberry leaves |
| title_full | Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини |
| title_fullStr | Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини |
| title_full_unstemmed | Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини |
| title_short | Валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини |
| title_sort | валідація алкаліметричної методики кількісного визначення вільних органічних кислот у листі малини |
| topic | малина листя вільні органічні кислоти алкаліметрія валідація |
| topic_facet | малина листя вільні органічні кислоти алкаліметрія валідація raspberry leaves free organic acids alkalimetry validation |
| url | https://ophcj.nuph.edu.ua/article/view/226278 |
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