Department Of Analytical Chemistry Research Articles

The Implementation of Industrial Work Culture as an Effort to Educate Students' Character in Qualitative Analysis Practical Learning for Grade XI of Analytical Chemistry Department at SMTI Yogyakarta Vocational School

This research aims to implement industrial work culture as an effort to educate students' character in practical learning of Qualitative Analysis for grade XI of Analytical Chemistry Department at SMTI Yogyakarta Vocational School. The research was carried out with a qualitative approach to survey results for students after completing the learning process with a block system lesson schedule, where students must comply with rules or regulations that instill discipline, responsibility and tough character. Students are required to submit practical reports within a certain time limit. The subjects in this research were eleventh-grade students of Analytical Chemistry Department at SMTI Yogyakarta Vocational School, totaling 32 students. The data were analyzed descriptively and present in tabular form. The results of the research showed that the majority agreed with the statements in the questionnaire given, where in the results of the evaluation survey of the block system learning schedule, 68.75% agreed that practical learning with the block system could improve student discipline and 31.25% strongly agreed. 59.38% agreed that practical learning with the block system could increase student’s endurance (physical and mental endurance) and 34.38% strongly agreed. 50.00% agreed that practical learning with the block system could train students to manage time and 43.75% strongly agreed. 46.88% agreed that practical learning with the block system could increase student learning motivation and 21.88% strongly agreed. 65.63% agreed that practical learning with the block system could further facilitate student’s level of understanding and 15.63% strongly agreed. Meanwhile, in the survey results regarding the rules for collecting practice reports with a certain time limit, 56.25% agreed that collecting practice reports with a certain time limit could improve student discipline and 31.25% strongly agreed. 59.38% agreed that collecting practice reports with a certain time limit could increase student’s endurance (physical and mental endurance) and 34.38% strongly agreed. 59.38% agreed that practical learning with the block system could train students to manage time and 28.13% strongly agreed. 46.88% agreed that practical learning with the block system could increase student learning motivation and 21.88% strongly agreed. Therefore, it can be concluded that the implementation of industrial work culture in the practical learning for grade XI of Analytical Chemistry Department at SMK-SMTI Yogyakarta Vocational School can be a character education effort, which is supported by the survey results, where the majority agreed with the statements in the questionnaire given to student representatives who were the objects of research

Analytical Chemistry is like the Fruit of an Apple Tree

Analytical chemistry is deeply rooted in Europe. It started with the work of Liebig and Fresenius, among others. Then Kirchhoff, as father of spectroscopy, contributed to the development of the modern instrumental analysis techniques flourishing today. As soon as I started learning analytical chemistry at university, I fell in love with it. At that time, I could not explain why I wanted to become an analytical chemist. Having gained experience teaching and performing research in analytical chemistry, I know now that I am attracted to it because this branch of chemistry is what an apple means to an apple tree - the fruit of a myriad of results in fundamental research in chemistry, always offering solutions to real life problems. I always wanted to become an analyst and to work at the analytical chemistry department where I studied. One year ago, my life drastically changed at the institute when I was invited to apply to lead the analytical chemistry department where I have been working since 2007. I must admit that I had mixed feelings in the beginning. First of all, I was honored that my colleagues in the department fully expressed their support. At the same time, I was confused and scared. I felt that I am not the right person to lead a department with a history of almost 120 years, that I had no clear vision of what could I do for my colleagues and for the students choosing our department. However, I wanted to express my gratitude to my colleagues for their trust in me. In my application, I advocated to maintain the high-quality teaching of analytical chemistry at the department and offered to implement challenge-based learning for students choosing our department. In past years, I felt that the raison d'être of analytical chemistry departments as single entities would soon end. My colleagues working in other fields such as biology, geography and geology, pharmacy and medicine, all purchased instrumental analytical equipment and started performing research by themselves. Recently, analytical chemistry departments underwent important organizational and structural changes. Some of them disappeared, others incorporated into their name environmental chemistry, food chemistry, or biochemistry. Recent advances in instrumental analysis create the impression that conducting chemical analysis is an easy task that no longer requires the expertise of chemists devoted to this branch of chemistry. However, there is still a lot of work to do, especially in the field of organic analytical chemistry. Thanks to innovations in mass spectrometry and related techniques, infrared spectroscopy, miniaturization (lab-on-chips) and sensors, ultra trace analysis, green methodologies, and elemental speciation, analytical chemistry is experiencing a second Golden Era. In last year alone, I was surprised by the ever-increasing number of chemistry bachelor and major students knocking on my door asking me to provide them with analytical chemistry-related research topics. That led me to contact faculty working at the other institutes offering cooperation with the arsenal of our instruments to widen the research topic choices in our department, advocating that we should unite and complement our efforts to create synergies. Surprisingly, the response of those colleagues was very positive. In one year, I could almost double the number of research topics for diploma work in our department. This is something that makes me happy and optimistic. I am confident that the development of analytical methods together with proper sampling and sample preparation are still important and crucial steps to produce high quality and reliable results. Moreover, participation of analytical chemists in these tasks is indispensable. The recent success of the Brazilian Journal of Analytical Chemistry achieving an impact factor of 0.7 makes me also think that analytical method development has still a bright future ahead. Long live Analytical Chemistry! Long live Brazilian Journal of Analytical Chemistry!

THEORETICAL AND EXPERIMENTAL APPROACHES IN THE STUDY OF ELECTROCHEMICAL AND THERMODYNAMIC PROPERTIES OF POLYFUNCTIONAL ORGANIC COMPOUNDS IN LIQUID-PHASE AND HETEROPHASE SYSTEMS

The publication reflects the experimental substantiation and fundamental development of some important ideas of the theory of the mutual influence of functional substitution in complex molecules of macrocyclic and chelating compounds on their coordination, solvation and redox properties, as well as the formation of algorithms for searching useful functions of these compounds. Researchers of the Analytical Chemistry Department of the Ivanovo State University of Chemistry and Technology have been studying the electrochemical and thermodynamic behavior of porphyrins, complexones, amino acids, peptides and the corresponding complexes with d- and f-metal ions, their influence on coordination, solvation and catalytic processes for a number of years. The results obtained together with the literature data are discussed in the review. For citation: Bazanov M.I., Berezina N.M., Gridchin S.N., Krutova O.N., Gorboletova G.G., Bychkova S.A., Lytkin A.I., Chernyavskaya N.V., Chernikov V.V., Volkov A.V. Theoretical and experimental approaches in the study of electrochemical and thermodynamic properties of polyfunctional organic compounds in liquid-phase and heterophase systems. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2023. V. 66. N 7. P. 98-110. DOI: 10.6060/ivkkt.20236607. 6839j.

Professor Ivo M. Raimundo Jr., a researcher concerned about the current state of science in Brazil, kindly granted BrJAC an interview

Ivo M. Raimundo Jr. holds a degree in chemistry (1983), a master’s degree in chemistry (1989), and a doctorate in analytical chemistry (1995), all from the Institute of Chemistry, University of Campinas (IQ-Unicamp), Brazil. He carried out postdoctoral studies at the University of Manchester Institute of Science and Technology (UMIST), Manchester, England (1997/98), and the University of South Carolina, Columbia, USA (2017). He is currently Associate Professor at the Department of Analytical Chemistry at IQ - Unicamp. He was Associate Director (2006–2009) and Director (2009–2015) of the Pluridisciplinary Center for Chemical, Biological and Agricultural Research (CPQBA) at Unicamp, Secretary of the Brazilian Chemical Society, Campinas Regional (2020-2022) and is currently its treasurer. He has served as an Associate Editor of the Journal of the Brazilian Chemical Society since 2019. Prof. Raimundo Jr has experience in instrumentation and automation in analytical chemistry, working mainly in the following areas: optical (nano)sensors, microfabrication of analytical systems, and laser-induced breakdown spectroscopy (LIBS).

When Colloidal Chemistry Meets Electrochemistry

AbstractThis invited Team Profile was created by the Laboratory of Electrochemistry, Electroanalytic, and Sensor Development (LEEDS), Department of Analytical Chemistry, Institute of Chemistry, University of Campinas, Brazil. They recently published an article about the origin of the zeta potential on an aqueous graphite dispersion prepared without passivating agents, with a minimal number of functional groups, and using concentrated ammonium hydroxide. Ammonia transfers electrons to graphite and raises the Fermi level of the carbon material above the original value. This electron excess generates the negative zeta potential, therefore it accounts for colloidal stability. “The Electronic Origin of the Zeta Potential is Supported by the Redox Mechanism on an Aqueous Dispersion of Exfoliated Graphite”, J. P. V. Damasceno, L. T. Kubota, Angew. Chem. Int. Ed. 2022, e202214995; Angew. Chem. 2022, e202214995

Analysis of Writing Programs and Students’ Errors to Increase the Students’ Writing Skill

This study presents the analysis of writing programs which can increase the students’ writing skill by concerning students’ errors. The method used qualitative and quantitative analyses. The participants involved in this study were 30 students of the third level majoring in analytical chemistry department in Politeknik AKA Bogor, academic year 2021/2022. The Researcher wanted to know the area of errors in each writing program. The result shows that the average of grade students got in the program of teaching reading and vocabulary was 68.75% with 31.25% error in the area of identifying the words: analysis, analyze, analytical, analyst, prepare, preparation, determine, determination, require, and statistically. In the program of teaching grammar and structure, the students’ score average was 70% which was bigger than the first program. Meanwhile the average of error was 30% in the area of using past tense, present tense, present perfect tense, modal auxiliary, passive voice, relative clause, past and present participle. In the next program, analyzing sentences from chemistry textbook, the students had difficulty in identifying main and relative clauses, and analyzing present and past participles in a sentence. The students obtained 71.25% for the average of grade and 28.75% error. In writing from simple to complex sentences, the students got score 77.5% and 22.5% error in the area of making sentences consisting of main and relative clauses and applying present and past participles as verb in a sentence. Finally, after having 4 programs stated above, in the program of writing practice report, the students got average of grade 80% meaning excellent, and 20% error in the area of interpreting data in writing and developing main idea. This research finds that the writing programs: teaching reading vocabulary, teaching grammar and structure, analyzing sentences from chemistry textbook, writing from simple to complex sentences, and writing practical report are the writing programs that can increase the students’ writing skill. To make the decision which area of writing programs needs to have more attention, it can be determined by analyzing the students’ errors.

THE 75TH ANNIVERSARY OF CHUNDAK STEPAN YURIYOVICH

S.Yu. Chundak born on March 30, 1947 in the village of Stripa. In 1965 he entered the first year of the chemical faculty of Uzhhorod National University, which graduated in 1970. During 1970-1974 he studied at postgraduate studies. In 1977 defended his dissertation for the degree of a candidate of chemical sciences, in 1988 he received the title of assistant professor. In 1996 he defended his dissertation for the degree of a doctor of chemical sciences, in 1998 he received the academic rank of professor. During 1992-2001 he worked as the head of the department of analytical chemistry, 2001-2020 – head Department of Ecology and Environmental Protection of Uzhhorod National University, since 2020, he has professor this Department. He is a specialist in coordinating chemistry, chemical engineering and ecology. Under his scientific guidance, 4 candidate dissertations and one doctoral dissertation are protected. Has more than 250 publications in professional international and national scientific publications, is the author of 16 patents for inventions and more than 30 educational and methodological aids for students of higher educational establishments.

Application of Pistacia atlantica Leaves Powder as Natural Material To Remove Nitrate and Phosphate Ions From Domestic Wastewater by Characterization, Bio-removal, and Phytotoxicity Studies

Application of Pistacia atlantica Leaves Powder as Natural Material To Remove Nitrate and Phosphate Ions From Domestic Wastewater by Characterization, Bio-removal, and Phytotoxicity StudiesObaida Alhajali1* , Adnan Ali-Nizam1 , Rasha Almostafa2 1Damascus University, Department of Plant Biology, Damascus, Syria.2International University for Science and Technology, Department of General and Analytical Chemistry, Syria. Abstract: Description of Pistacia leaves powder using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), Energy-dispersive X-ray spectroscopy (EDX), specific surface area according to nitrogen adsorption (SBET) and methylene Blue (MB), and point of zero charge determination (pHpzc). A series of batch adsorption tests were conducted to study effect of various factors (plant powders dose, contact time, temperature, pH) on the percentage of nitrate and phosphate removal from domestic wastewater. The adsorption kinetics, regeneration ability test of plant powder, and phytotoxicity tests for treated water and spent powder on germination were studied. Results of SBET analysis showed that Pistacia leaves powders have a low surface area and microscopic pores, SEM images revealed rough surfaces with uneven cavities, EDX analysis showed that there are high percentages of carbon and oxygen, good percentages for nitrogen, and few percentages of potassium, calcium, magnesium, phosphorous, sulfur and chlorine, and FTIR analysis showed that there are more than five distinct absorption peaks. The maximum value of nitrate and phosphate removal was 76.47% and 52.20%, respectively, at powder dose of 2 g/L, temperature 25 °C, and pH 5, and the percentage of nitrate and phosphate removal increased with increasing contact time until equilibrium was reached after 120 min for nitrate and 180 min for phosphate, and It was found that adsorption of ions follows kinetics of reaction from pseudo-second-order model, and powders can be Regeneration and used for two successive cycles with a slight decrease in removal efficiency. Germination tests on Lepidium sativum indicate no phytotoxicity. That is, Pistacia leaves powder is one of the natural products that are effective in removing nitrate and phosphate from domestic wastewater.

Liquid chromatography at the University of Pardubice: A tribute to Professor Pavel Jandera

Pavel Jandera was a world-leading analytical chemist who devoted his entire professional life to research in the field of high-performance liquid chromatography. During all his scientific career, he worked at the Department of Analytical Chemistry at the University of Pardubice, Czech Republic. His greatest contribution to the field of liquid chromatography was the introduction of a comprehensive theory of liquid chromatography with programmed elution conditions. He was also involved in the research of gradient elution techniques in preparative chromatography, modeling of retention and selectivity in various phase systems, preparation of organic monolithic microcolumns and, last but not least, in the development of theory and practical applications of two-dimensional liquid chromatography, mainly in the comprehensive form. In this review article, we have tried to capture the highlights of his scientific career and provide the readers with a detailed overview of Pavel Jandera's contribution to the evolution of separation sciences. This article is protected by copyright. All rights reserved.

Five Years of Advanced Archaeometric Analysis at the Department of Analytical Chemistry, Faculty of Science, Palacký University in Olomouc

In modern archaeological research, a close multidisciplinary collaboration with other scientific areas is necessary, especially with natural sciences (e.g., anthropology, archaeobotany, and chemistry). This kind of collaboration and mutual evaluation of obtained results provides synergistically a series of important information in the context of prehistoric research nowadays. This systematic cooperation among archaeology, heritage science, anthropology, archaeobotany and analytical chemistry has been intensively developed for last five years at the Department of Analytical Chemistry, Faculty of Science, Palacký University in Olomouc. The aim of this short communication is to introduce our workplace and its activities with a focus on the most important outputs from various areas of the archaeometric research.

Розвиток хроматографії на кафедрі аналітичної хімії Київського національного університету імені Тараса Шевченка

An information about teaching and scientific activities in the field of chromatographic methods of analysis at the Department of Analytical Chemistry of the National Taras Shevchenko University of Kiev for the period from the 70s of the twentieth century till present days given. The perspective directions of the development of academic disciplines and scientific research of the department in this area are outlined.

The key role of mass spectrometry in comprehensive research on new psychoactive substances

This month's Special Feature is authored by four accomplished investigators from the Department of Physical and Analytical Chemistry, University Jaume I, Castellón de la Plana, Spain. In their article, Dr. Ibáñez and colleagues direct their attention towards issues relating to new psychoactive substances (NPS), or emerging designer drugs, a heterogeneous group of compounds that aim to mimic the actions of ‘classical’ illicit drugs and circumvent scheduling guidelines. Each year these drugs contribute to a growing number of drug-related adverse events and deaths. The authors describe their work by way of a three-step strategy for the analysis of these agents by mass spectrometry: first, detection and analytical characterization of the NPS; second, metabolic and pharmacokinetics studies to select the most suitable biomarkers of their consumption; and third, the detection, identification and quantification of these biomarkers in biological tissues and fluids. They discuss the application of a range of mass spectrometric techniques, including conventional approaches such as combined liquid chromatography-mass spectrometry, but also the more recent adoption of direct ionization sources for the rapid identification of seized lots of drugs. To illustrate their points this Special Feature focuses on two model psychoactive substances: the synthetic cannabinoid XLR-11 and the synthetic cathinone 5-PPDi. Their Special Feature illustrates some of the challenges involved in the analysis of new psychoactive substances and highlights the essential role of mass spectrometry in this important and rapidly evolving area.

Topicality of teaching analytical toxicology at the National University of Pharmacy

Aim. To analyze the methods of teaching analytical toxicology in the National University of Pharmacy (NUPh).
 Materials and methods. Analytical, systematic, logical methods of teaching the discipline, as well as scientific publications of domestic and foreign scientists were used.
 Results. The topicality of teaching the discipline “Analytical toxicology” at the Department of Analytical Chemistry and Analytical Toxicology of the NUPh (Kharkiv) has been discussed in the article. The features of teaching the discipline in current conditions have been analyzed. The possibility of conducting the chemico-toxicological analysis, which results are necessary for solving many legal and other important issues, has been described. The main tasks facing analytical toxicology, its difference from analytical chemistry and other pharmaceutical disciplines, as well as the significance of the knowledge gained by applicants for higher education that they need in their further practical activities have been considered.
 The structure of the educational process when studying the discipline “Analytical toxicology”, including theoretical and practical sections, is presented. Modern chemical and physicochemical methods of analysis widely used in analytical toxicology have been described.
 Conclusions. To train applicants for higher education in the specialty 226 “Pharmacy, Industrial pharmacy”, the study of the discipline “Analytical toxicology”, which is closely related to chemical, biological and medical disciplines, is important. The knowledge gained by applicants for higher education makes it possible to correctly understand the fundamentals of analytical toxicology, apply the theoretical and practical skills obtained in their further practical activities and become fully qualified specialists in the field of chemico-toxicological analysis.
 Key words: analytical toxicology; analytical chemistry; chemico-toxicological analysis; intoxication; toxicant.

Organization of distance education in chemistry in higher education

The study focuses on the problems of distance learning in higher natural science education (using the example of chemical education). The issues of history of development of means and methods of e-learning using remote educational technologies are discussed. The study focuses on the activities of the Department of Analytical and Physical Chemistry of Astrakhan State University in the field of organizing and conducting classes in specialized chemical disciplines with students during the period of self-isolation. Attention is paid to the organization and conduct of distance learning during the period of self-isolation, through the Moodle virtual educational environment. Advantages and disadvantages of distance learning, difficulties of conducting classes in a distance form in the discipline of “chemistry,” as well as factors ensuring obtaining quality education are considered.

DEVELOPMENT OF TECHNOLOGIES FOR OBTAINING ACTIVE PHARMACEUTICAL INGREDIENTS, MEDICINAL AND DIAGNOSTIC PREPARATIONS BASED ON LIPIDS IN UKRAINE

In Ukraine, for 45 years (1975-2020), biotechnological and bionanotechnological studies were conducted to obtain lipid active phar­maceutical ingredients and create diagnostic and medicinal products. Phospholipids and glycolipids are important participants in biological reactions. Methods for obtaining highly purified phospholipid and ganglioside ingredients are proposed using technologi­cal methods of lipid chemistry and biotechnology. The authors have studied physicochemical and biological properties of phospholi­pids and gangliosides. The structure of the isolated lipid substances was confirmed. The studies of biological activity of the ganglio­sides with a number of models have confirmed their high biological activity: antiviral, reparative, immunostimulating. The studies allowed for creation a number of diagnostic lipid antigens and drugs, that were implemented in production in Ukraine and other countries. For the first time in CIS in Ukraine, liposomal forms of preparations having antitumor, antioxidant, anti-inflammatory and membrane-protective pharmacological properties have been developed. The scope of biotechnology application in this field is con­stantly expanding and is of interest to practical medicine and business now. And while the issues in this area are still far from over, it is already obvious that this line of research will allow for raising to a new level the development of methods of diagnosis and treat­ment of human diseases in the future. It should be noted that biotechnological studies lipids and liposomal forms are the basis of this line of research. Nanoforms of pharmaceuticals, in particular liposomes, can solve the problem of giving new unique properties to known active pharmaceutical ingredients and consequently increase therapeutic efficacy. Research on obtaining liposomal drugs based on hydrophobic antioxidants is carried out at the Department of Biotechnology, Biophysics and Analytical Chemistry, NTU "KhPI".

Enrique San Román (1945–2019)

An homage to the Argentinian Photochemist Enrique San Román is presented. Enrique led the Photochemistry and Chemical Kinetics research group in the Department of Inorganic, Analytical and Physical Chemistry in the Faculty of Exact and Natural Sciences of the University of Buenos Aires from 1984 until his death in July 2019. He left a strong legacy in Chemical Kinetics and Photochemistry in Argentina. He is remembered as a meticulous and very knowledgeable scientist and teacher, a loyal friend and a generous and integer human being.

Uv Spectrophotometric Methods for Determination of Sofosbuvir in Pure Form and Pharmaceutical Dosage Forms in Presence of Its Alkaline Degradate

Aims: Two spectrophotometric methods were developed and validated for the determination of sofosbuvir in presence of its alkaline degradate.
 Study Design: Ratio difference and ratio derivative methods were assisted for determination of sofosbuvir in presence of its alkaline degradate, laboratory-prepared mixtures and in tablet dosage forms.
 Place and Duration of Study: Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy (Girls), Al - Azhar University, between December 2019 and January 2020.
 Methodology: Two analytical methods were achieved and validated for the quantitative determination of Sofosbuvir in presence of its alkaline degradate. The first method was ratio difference (RD) method, where the UV absorption spectra of different concentrations of sofosbuvir were divided by the spectrum of a certain concentration (15 µg mL-1) as a devisor of its alkaline degradate to get the ratio difference spectra. Afterwards, the peak amplitudes difference between 253.7 and 243.5 nm were measured. The second method was the ratio derivative (1DR) method, where the first derivative of the ratio spectra (1DR) was obtained and its amplitude was measured at 247 and 268 nm. Good linearity was obtained over the concentration range of 3-15 µg mL-1 for the proposed methods. The proposed procedures were adopted for the selective determination of intact Sofosbuvir in presence of up to 80% of its degradation product. Sofosbuvir was exposed to different conditions as alkaline, acidic and oxidative degradation.
 Results: The proposed methods were developed and validated with good linearity range of 3-15 µg mL-1 for both methods, and also with good accuracy and precision. And the obtained results were statistically compared to those obtained by the reported method.
 Conclusion: Sofosbuvir was successfully determined by the proposed ratio difference and ratio derivative methods in bulk powder, laboratory prepared mixtures and tablet dosage form with good accuracy and precision. The methods were validated according to ICH guidelines. The results obtained were compared with those of the reported method and were found to be in good agreement.

Essential oil composition of Artemisia abrotanum L. during different vegetation stages in Lithuania

Artemisia abrotanum L. was introduced in the Middle of Lithuania Collection of Spice–Melliferous Plants of the Scientific Sector of Medicinal and Aromatic Plants of the Botanical Garden ex situ at Vytautas Magnus University since 1980. The object of investigation was Artemisiae abrotani herba of Artemisia abrotanum L. All samples were collected at different vegetation stages: growth and leaf production, flower bud development, the beginning of flowering, massive flowering and the end of flowering. Essential oils were obtained by hydrodistillation. The chemical composition of the essential oils of Artemisiae abrotani herba was studied by GC/MS in the Department of Analytical and Toxicological Chemistry at the Lithuanian University of Health Science in 2018–2019. Fifty-six compounds of the oil were identified, of which (+)-piperitone was the major component (20.38–38.48%). The data in this study showed a remarkable quantitative variation of constituents in the essential oils. The highest content and diversity of compounds was determined during the flower bud development stage. Sixty identified compounds in this stage reached 76.6% of the identified oil content. The highest concentration of this compound (38.48%) was detected at the end of the flowering vegetation stage and the lowest amount (20.38%) was found during the growth and leaf production. Among the other major compounds were (+)-piperitone, 1,4-cineole, lavandulyl butyrate, aromandendrene and isogermacrene D.

Validated Stability Indicating HPTLC and UV-Spectrophotometric Techniques for the Determination of Avanafil

Aims: To develop methods with complete validation according to ICH guidelines and to be applied for the determination of avanafil in pure form and in pharmaceutical formulation in the presence of its degradation products.
 Study Design: High performance thin layer chromatography (HPTLC) and different spectrophotometric methods (dual wavelength, first derivative, first derivative of ratio spectra and ratio difference are developed for simultaneous determination of avanafil in laboratory-prepared mixtures of avanafil with its degradation products and in pharmaceutical formulation.
 Place and Duration of Study: Sample: Department of Analytical Chemistry, Faculty of Pharmacy (Girls), Al-Azhar University, Cairo, Egypt, between May 2019 and September 2019.
 Methodology: Two techniques have been developed for the determination of avanafil in the presence of its degradation products. The first was HPTLC where separation was performed on silica gel 60 F254 plates, with chloroform: toluene: methanol: conc. ammonia (6:5:3:0.1, by volume) as a developing system and UV detection at 230 nm. The second one was UV- spectrophotometry which included dual wavelength between 267 and 292 nm, first derivative determination of the drug at 261 nm, first derivative of ratio of peak amplitudes at 275.6, 305.4 and 329 nm and the ratio difference with the amplitude difference between (266 and 250 nm).
 Results: HPTLC method was applied over the concentration range of 0.5-5. μg/spot, while spectrophotometric methods were linear over the concentration range 5-50 μg/mL for avanafil.
 Conclusion: Novel, simple and accurate method for the determination of avanafil in laboratory-prepared mixtures of avanafil with its degradation products and in pharmaceutical formulation.

Hollow Cathode and New Related Analytical Methods

History of the development of a hollow cathode as a version of a discharge cell for optical emission spectroscopy and glow-discharge mass spectrometry is discussed. Special attention was paid to the contribution of colleagues from the Department of Analytical Chemistry at the St. Petersburg State University to research, development, and implication of analytical systems with glow discharge, including discharge in a hollow cathode. New analytical methods developed on its basis and versions of their application are described, covering direct elemental and isotopic analysis, depth profiling, determination of hardly ionized elements in solid-phase samples of different conductivity, and the determination of volatile organic compounds in the air.