scholarly journals An effective method for preparation of high purity oligohexamethylene guanidine salts

2020 ◽  
Vol 15 (3) ◽  
pp. 31-38
Author(s):  
I. S. Ivanov ◽  
D. O. Shatalov ◽  
S. A. Kedik ◽  
I. P. Sedishev ◽  
S. V. Beliakov ◽  
...  
Keyword(s):  
High Purity ◽  
High Performance ◽  
Standard Sample ◽  
Preparation Method ◽  
Guanidine Hydrochloride ◽  
New Drugs ◽  
Quantitative Content ◽  
Significant Difference ◽  
The Russian Federation ◽  
Standard Sample Solution

Objectives. Given that microorganisms can become resistant to certain groups of drugs and considering also their ability to form biofilms, the development of new drugs that are active against adapted microflora is required. This study focused on the development of a new method for the synthesis of a promising compound, the branched hydrosuccinate oligohexamethylene guanidine (OHMGsucc), with high purity that meets the standards of the 14th edition State Pharmacopeia of the Russian Federation (SPRF). Previously proposed methods have managed to isolate this product, which, however, complies with the requirements of the outdated SPRF. Therefore, the main aim of this study was to update the regulatory framework for the indicated OHMG salt for its further use in the pharmaceutical industry according to modern standards.Methods. To control the residual impurities of hexamethylenediamine (HMDA) and guanidine hydrochloride (GHC), high-performance liquid chromatography (HPLC) was applied using a Thermo Scientific Dionex UltiMate 3000 chromatograph, and the chromatographic signals of the test solution with those of a standard sample solution obtained by a previously published conventional method were compared.Results. The HPLC experimental data indicated a significant difference in the quantitative content of HMDA and GHC observed for the new and older preparation method of the branched OHMGsucc, suggesting that the method disclosed in this article can be used to obtain highly pure OHMGsucc.Conclusions. The specified compound was standardized with the parameter “related impurities” according to the current (14th) edition of the SPRF. The effectiveness and reproducibility of the proposed method was experimentally confirmed. In addition, a process diagram for the preparation of the indicated OHMG salt was prepared.

Analysis of caffeine and chlorogenic acids content regarding the preparation method of coffee beverage

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Alica Bobková ◽  
Silvia Jakabová ◽  
Ľubomír Belej ◽  
Lukáš Jurčaga ◽  
Jozef Čapla ◽  
...  
Keyword(s):  
Chlorogenic Acid ◽  
Coffea Arabica ◽  
High Performance ◽  
Dry Matter ◽  
Preparation Method ◽  
Matter Content ◽  
Dry Matter Content ◽  
Chlorogenic Acids ◽  
Filtration Method ◽  
Significant Difference

Abstract This research was focused on the evaluation of selected parameters of coffee quality, regarding the beverage preparation method, using high-performance liquid chromatography. Samples of Coffea arabica from South America were analyzed. For the preparation of the final beverage were used filtration and moka methods. All samples roasted at medium dark roasting level Full City ++, contained less than 5% of moisture. The values of pH and dry matter content did not show a significant difference. The lowest content of chlorogenic acid reached value (1.41 g·100 g−1) prepared from filtration and 1.49 g·100 g−1 prepared from moka method. The highest content of chlorogenic acid ranged from 2.94 g. 100 g−1 filtration method and 3.36 g. 100 g−1 moka. Similarly, caffeine content, showed lower values using the filtration method. Values ranged from 1.37 to 1.57% (filtration) and from 1.54 to 1.78% (moka). However, PCA didn’t show a significant difference.

scholarly journals Determination of catechins in green tea leaves by HPLC compared to spectrophotometry

2021 ◽  
Vol 19 (3(75)) ◽  
pp. 28-33
Author(s):  
Oleksandr Yu. Maslov ◽  
Mykola A. Komisarenko ◽  
Yulia S. Kolisnyk ◽  
Tatyana A. Kostina
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Green Tea ◽  
High Performance ◽  
Raw Material ◽  
Qualitative Composition ◽  
Tea Leaves ◽  
Quantitative Content ◽  
Significant Difference ◽  
Green Tea Leaves

Aim. To study the qualitative composition, the quantitative content of catechins in green tea leaves and compare the data obtained with those evaluated by spectrophotometry.Materials and methods. Green tea leaves used for the analysis were collected in Anhui Province, China. The extract for the HPLC analysis was obtained by the maceration method with 60 % ethanol twice in the raw material/extractant ratio of 1 : 20. In the case of the spectrophotometric analysis, green tea leaves were extracted with 70 % ethanol twice by the maceration method in the raw material/extractant ratio of 1 : 20. The analysis of the extract from green tea leaves was performed by high performance liquid chromatography using a Prominence LC-20 Shimadzu chromatographic system (Japan) with a SPD-20AV spectrophotometric detector, an Agilent Technologies Microsorb-MV-150 column (reversed phase, C18 modified silica gel, length – 150 mm, diameter – 4.6 mm, particles size – 5 μm). Substances in the extract were identified by comparing the retention time and the spectral characteristics of the test substances with the same characteristics of the reference standards. Spectrophotometric measurements were carried out using a UV-1000 single beam spectrophotometer (China) with the pair of S90-309Q quartz square cells.Results and discussion. Using high performance liquid chromatography 5 catechins were identified. Among them epigallocatechin-3-O-gallate (10.85 %) predominated, while catechin (0.61 %) had the lowest concentration. The total amount of catechins in green tea leaves was 30.56 and 24.79 % by HPLC and spectrophotometry, respectively. The F- and t-tests showed that there was no significant difference between the results of HPLC and spectrophotometry.Conclusions. The qualitative composition and the quantitative content of catechins have been determined in the extract from green tea leaves by high performance liquid chromatography and spectrophotometry. Both HPLC and spectrophotometric methods can be used to determine the total catechin content in green tea leaves. The high content of catechins makes the extract promising for further study and creation of new herbal medicinal products and dietary supplements. The results obtained will be used for standardization of green tea leaves and for future pharmacological research of its extract.

MEDICAL SAVINGS ACCOUNTS AS A TOOL FOR INCREASING DOCTORS ' SALARIES AND MOTIVATING RUSSIAN CITIZENS TO HIGH-PERFORMANCE WORK AND A HEALTHY LIFESTYLE

2020 ◽  
Vol 2 (7) ◽  
pp. 24-31
Author(s):  
E. V. SOKOLOV ◽  
◽  
E. V. KOSTYRIN ◽  
Keyword(s):  
Labor Productivity ◽  
Russian Federation ◽  
High Performance ◽  
Healthy Lifestyle ◽  
Medical Personnel ◽  
Increase Labor Productivity ◽  
Healthcare Financing ◽  
Savings Accounts ◽  
Medical Savings Accounts ◽  
The Russian Federation

The article proves that it is impossible to achieve a significant increase in the salary of medical personnel within the existing system of healthcare financing of the Russian Federation, namely, in accordance with the “may” Decrees of 2012 by V. V. Putin, to bring the salary of doctors to a level twice higher than the average for the region by 2018. It is proved that to achieve the necessary results in terms of increasing doctors’ salaries and motivating citizens to increase labor productivity and a healthy lifestyle, it is necessary to transfer the system of healthcare financing within the framework of obligatory medical insurance to medical savings accounts.

scholarly journals Recent advances in skin collagen: functionality and non-medical applications

2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Yanting Han ◽  
Jinlian Hu ◽  
Gang Sun
Keyword(s):  
Smart Materials ◽  
High Performance ◽  
Preparation Method ◽  
Chemical Reactivity ◽  
Medical Field ◽  
Recent Advances ◽  
Synthetic Materials ◽  
Skin Collagen ◽  
Promising Area ◽  
Living Organisms

Abstract During nature evolution process, living organisms have gradually adapted to the environment and been adept in synthesizing high performance structural materials at mild conditions by using fairly simple building elements. The skin, as the largest organ of animals, is such a representative example. Conferred by its intricate organization where collagen fibers are arranged in a randomly interwoven network, skin collagen (SC), defined as a biomass derived from skin by removing non-collagen components displays remarkable performance with combinations of mechanical properties, chemical-reactivity and biocompatibility, which far surpasses those of synthetic materials. At present, the application of SC in medical field has been largely studied, and there have been many reviews summarizing these efforts. However, the generalized view on the aspects of SC as smart materials in non-medical fields is still lacking, although SC has shown great potential in terms of its intrinsic properties and functionality. Hence, this review will provide a comprehensive summary that integrated the recent advances in SC, including its preparation method, structure, reactivity, and functionality, as well as applications, particularly in the promising area of smart materials. Graphical abstract

scholarly journals Delivery of Thyronamines (TAMs) to the Brain: A Preliminary Study

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1616
Author(s):  
Nicoletta di Leo ◽  
Stefania Moscato ◽  
Marco Borso' ◽  
Simona Sestito ◽  
Beatrice Polini ◽  
...  
Keyword(s):  
High Performance ◽  
In Vitro Model ◽  
New Drugs ◽  
Therapeutic Approaches ◽  
Neuroprotective Effects ◽  
Pharmacological Response ◽  
Preliminary Study ◽  
Vitro Model ◽  
The Brain

Recent reports highlighted the significant neuroprotective effects of thyronamines (TAMs), a class of endogenous thyroid hormone derivatives. In particular, 3-iodothyronamine (T1AM) has been shown to play a pleiotropic role in neurodegeneration by modulating energy metabolism and neurological functions in mice. However, the pharmacological response to T1AM might be influenced by tissue metabolism, which is known to convert T1AM into its catabolite 3-iodothyroacetic acid (TA1). Currently, several research groups are investigating the pharmacological effects of T1AM systemic administration in the search of novel therapeutic approaches for the treatment of interlinked pathologies, such as metabolic and neurodegenerative diseases (NDDs). A critical aspect in the development of new drugs for NDDs is to know their distribution in the brain, which is fundamentally related to their ability to cross the blood–brain barrier (BBB). To this end, in the present study we used the immortalized mouse brain endothelial cell line bEnd.3 to develop an in vitro model of BBB and evaluate T1AM and TA1 permeability. Both drugs, administered at 1 µM dose, were assayed by high-performance liquid chromatography coupled to mass spectrometry. Our results indicate that T1AM is able to efficiently cross the BBB, whereas TA1 is almost completely devoid of this property.

scholarly journals Metabolomic analysis reveals the interaction of primary and secondary metabolism in white, pale green, and green pak choi (Brassica rapa subsp. chinensis)

2021 ◽  
Vol 64 (1) ◽  
Author(s):  
Hyeon Ji Yeo ◽  
Seung-A Baek ◽  
Ramaraj Sathasivam ◽  
Jae Kwang Kim ◽  
Sang Un Park
Keyword(s):  
Secondary Metabolites ◽  
Brassica Rapa ◽  
High Performance ◽  
Reducing Power ◽  
Total Phenolic ◽  
Pak Choi ◽  
Primary And Secondary Metabolites ◽  
Chlorophyll Contents ◽  
Significant Difference ◽  
Pale Green

AbstractThis study aimed to comprehensively analyze primary and secondary metabolites of three different-colored (white, pale green, and green) pak choi cultivars (Brassica rapa subsp. chinensis) using gas chromatography attached with time-of-flight mass spectrometry (GC-TOFMS) and high-performance liquid chromatography (HPLC). In total, 53 primary metabolites were identified and subjected to partial least-squares discriminant analysis. The result revealed a significant difference in the primary and secondary metabolites between the three pak choi cultivars. In addition, 49 hydrophilic metabolites were detected in different cultivars. Total phenolic and glucosinolate contents were highest in the pale green and green cultivars, respectively, whereas total carotenoid and chlorophyll contents were highest in the white cultivar. Superoxide dismutase activity, 2,2-diphenyl-1-picrylhydraz scavenging, and reducing power were slightly increased in the white, pale green, and green cultivars, respectively. In addition, a negative correlation between pigments and phenylpropanoids was discovered by metabolite correlation analysis. This approach will provide useful information for the development of strategies to enhance the biosynthesis of phenolics, glucosinolates, carotenoids, and chlorophyll, and to improve antioxidant activity in pak choi cultivars. In addition, this study supports the use of HPLC and GC-TOFMS-based metabolite profiling to explore differences in pak choi cultivars.

Evaluation of the Interference of Hemoglobin Variant J-Bangkok on Glycated Hemoglobin (HbA1c) Measurement by Five Different Methods

2017 ◽  
Vol 125 (10) ◽  
pp. 655-660
Author(s):  
Dong-Mei Wen ◽  
Sheng-Nan Xu ◽  
Wei-Jia Wang ◽  
Xiu-Ming Zhang ◽  
Ming-Huan Suo ◽  
...  
Keyword(s):  
High Performance ◽  
Glycated Hemoglobin ◽  
Clinical Laboratory ◽  
Hemoglobin Variant ◽  
Deming Regression ◽  
Significant Difference ◽  
The Difference ◽  
Immuno Assay ◽  
Hba1c Measurement ◽  
Significant Interference

Abstract Objective The interference of the hemoglobin variant (Hb J-Bangkok) was evaluated on 4 different glycated hemoglobin assays and compared with a reference immuno assay. Methods An overall test of coincidence of 2 least-squares linear regression lines was performed to determine whether the presence of Hb J-Bangkok caused a statistically significant difference in HbA1c results compared with a reference immuno assay. Statistical analysis was performed on the difference of the estimated average glucose calculated from HbA1c values and fasting plasma glucose in the Hb J-Bangkok variant group using the different detection systems. Deming regression analysis was used to determinate whether Hb J-Bangkok had a significant interference on HbA1c results using an HbA1c±10% relative bias at 6% and 9% HbA1c as evaluation limits. Results Turbidimetric inhibition immunoassay method, and enzymatic methods were not affected by Hb J-Bangkok. However, Hb J-Bangkok showed statistically significant interference to the two ion-exchange high-performance liquid chromatography methods. Conclusion When performing HbA1c tests, clinical laboratory personnel should identify the Hb variant and select the appropriate methods or use alternative indicators.

Content of amino acids in raw materials of somespecies of ASTERACEAE family

Fitoterapia ◽  
2020 ◽  
Vol 3 (3) ◽  
pp. 44-50
Author(s):  
S.M. Marchyshyn ◽  
◽  
L.V. Slobodianiuk ◽  
R.Yu. Basaraba ◽  
N.А. Hudz ◽  
...  
Keyword(s):  
Amino Acids ◽  
High Performance Liquid Chromatography ◽  
Free Amino ◽  
High Performance ◽  
Raw Materials ◽  
Essential Amino Acids ◽  
Qualitative Composition ◽  
Quantitative Content ◽  
First Time ◽  
Asteraceae Family

Keywords: amino acids; common pussytoes; yacon; stevia; golden marigolds; leaves; herb; aster family; high performance liquid chromatography. For the first time the qualitative composition was studied and the quantitative content of amino acids in the herb of common pussytoes, yacon leaves, stevia leaves, herb of golden marigolds was determined by HPLC. 17 bound and 16 free amino acids were identified in the herb of common pussytoes, in the herb of golden marigolds, yacon leaves and stevia leaves – 12 and 5, 17 and 11 and 16 and 14 amino acids, respectively. The highest content of the sum of essential and substitute amino acids is contained in the leaves of stevia; the lowest content of the sum of essential amino – in the herb of golden marigolds, the sum of essential amino acids – in the herb of common pussytoes.

Preparing high purity λ-Ti3O5 and Li/λ-Ti3O5 as a high performance electromagnetic wave absorber

2021 ◽  
Author(s):  
xiankai fu ◽  
Wanqi Chen ◽  
Xiaowen Hao ◽  
Zhimin Zhang ◽  
Ruolan Tang ◽  
...  
Keyword(s):  
Electromagnetic Wave ◽  
Microwave Absorption ◽  
High Purity ◽  
High Performance ◽  
Room Temperature

This paper reports a new candidate material λ-Ti3O5 for microwave absorption. λ-Ti3O5 has been proposed to be metastable and has emerged at room temperature only in the form of nanocrystals....

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