Chemistry in human life. Topic: the role of chemistry in medicine The significance of chemistry for modern medicine in brief
“Chemistry 11th grade” - Microlaboratories for chemical experiments. Biological-chemical profile Information-chemical profile Chemical-mathematical profile. Educational electronic publication. The content of the course at the profile level is provided by: Chemistry (grades 8 – 11). Complex chemical compounds in everyday life. 10th grade – 3 lessons per week + 1 hour of elective courses 11th grade – 3 lessons per week.
"Organic chemistry" - Method of half-reactions. Let's consider what happened to the MnO4- ion. Electronic balance method. Oxidation state in organic chemistry. The MnO4 ion has turned into Mn2+. The electrons were accepted by the MnO4- ion. OVR in organic chemistry. The MnO4 ion has completely lost 4 oxygen atoms. The MnO4- ion is an oxidizing agent. Advantages of the half-reaction method.
“Computers in Medicine” - Based on the symptoms generated by the computer, the student must determine the course of treatment. Computers are used to create maps showing how quickly epidemics spread. Computer technology is used to train medical workers in practical skills. What and how have we learned about the use of computers in medicine?
“History of Chemistry” - P 9. Evaporation of liquid mercury. L 4. Wood burning. Agricola mining. DI. Mendeleev. Physical. I 11.Formation of rust on a nail. Egyptian priests. Reformers. Theory of the structure of organic substances 1869. Aristotle. Law of conservation of mass of substances 1756. A 3. Evaporation of water. E 7. Blackening of silver items.
“Mathematics in Medicine” - Mathematical statistics. Mathematics and medicine. Cardiology. Much attention is paid to the conclusions and interpretation of the calculation results. Mathematics is especially important in pharmaceuticals. Both biology and medicine make extensive use of mathematical statistics. Pharmaceuticals.
“Physics in Medicine” - A powerful laser beam of appropriate diameter destroys a malignant tumor. X-ray examination of human organs. Radiodiagnostics. Plasma scalpel. A plasma scalpel cuts through tissue and bones without blood. Physics helps diagnose diseases. Physics. To help the surgeon, miniature generators of high-temperature plasma were created.
INTRODUCTION
Chemists of the second half of the 20th century continued the work of their ancestors and were very actively involved in the study of living nature. This thesis can be supported at least by the fact that out of 39 Nobel Prizes in chemistry awarded over the past 20 years (1977-1996), 21 prizes (more than half! and there are a lot of branches of chemistry) were received for solutions to chemical and biological problems. This is not surprising, because a living cell is a real kingdom of large and small molecules that continuously interact, form and disintegrate... About 100,000 processes take place in the human body, each of them representing a combination of various chemical transformations. Approximately 2,000 reactions can occur in one cell of the body. All these processes are carried out using a relatively small number of organic and inorganic compounds. Modern chemistry is characterized by a transition to the study of complex organoelement compounds consisting of inorganic and organic residues.
Chapter 1. MODERN CHEMISTRY AND MEDICINE
Inorganic parts are represented by water and ions of various metals, halogens and phosphorus (mainly), organic parts are represented by proteins, nucleic acids, carbohydrates, lipids and a fairly large group of low-molecular bioregulators, such as hormones, vitamins, antibiotics, prostaglandins, alkaloids, growth regulators and etc.
For modern doctors and pharmacists, the study of inorganic chemistry is also of great importance, since many drugs are inorganic in nature. Therefore, physicians must clearly know their properties: solubility, mechanical strength, reactivity, impact on humans and the environment.
Modern medicine widely studies the relationship between the content of chemical elements in the body and the occurrence and development of various diseases. It turned out that the body reacts especially sensitively to changes in the concentration of microelements in it, that is, elements present in the body in quantities less than 1 g per 70 kg of human body weight. These elements include copper, zinc, manganese, molybdenum, cobalt, iron, and nickel.
Of the non-metalloids in living systems, one can almost always find atoms of hydrogen, oxygen, nitrogen, carbon, phosphorus and sulfur in organic compounds and atoms of halogens and boron both in the form of ions and in organic particles. Deviations in the content of most of these elements in living organisms often lead to quite severe metabolic disorders.
Most diseases are caused by deviations in the concentrations of some substance from the norm. This is due to the fact that a huge number of chemical transformations inside a living cell occur in several stages, and many substances are not important to the cell in themselves, they are only intermediaries in a chain of complex reactions; but, if some link is broken, then the entire chain as a result often ceases to fulfill its transfer function; the normal work of the cell in the synthesis of necessary substances stops.
It has been proven that changes in the concentration of zinc are associated with the course of cancer, cobalt and manganese - diseases of the heart muscle, nickel - blood clotting processes. Determining the concentration of these elements in the blood sometimes makes it possible to detect the early stages of various diseases. Thus, changes in the concentration of zinc in the blood serum are associated with the course of diseases of the liver and spleen, and the concentrations of cobalt and chromium are associated with some cardiovascular diseases.
Organic molecules play a very important role in maintaining the normal functioning of the body. They can be divided according to the principles inherent in their design into three groups:
biological macromolecules (proteins, nucleic acids and their complexes), oligomers (nucleotides, lipids, peptides, etc.) and monomers (hormones, antibiotics, vitamins and many other substances).
For chemistry, it is especially important to establish a connection between the structure of a substance and its properties, in particular its biological action. For this purpose, many modern methods are used that are part of the arsenal of physics, organic chemistry, mathematics and biology.
In modern science, on the border of chemistry and biology, many new sciences have arisen, which differ in the methods used, goals and objects of study. All these sciences are usually united under the term “physico-chemical biology”. This direction includes:
a) chemistry of natural compounds (bioorganic and bioinorganic chemistry bioorganic chemistry and inorganic biochemistry, respectively);
b) biochemistry;
c) biophysics;
d) molecular biology;
e) molecular genetics;
f) pharmacology and molecular pharmacology and many related disciplines. In most modern biological research, chemical and physicochemical methods are actively used. Progress in such branches of biology as cytology, immunology and histology was directly related to the development of chemical methods for the isolation and analysis of substances. Even such a classical “purely biological” science as physiology is increasingly using the achievements of chemistry and biochemistry. In the USA, the National Institutes of Health USA currently funds areas of medical science related to purely physiological research much less than biochemical research, considering physiology an “unpromising and outdated” science. Sciences that seem exotic at first glance are emerging, such as molecular physiology, molecular epidemiology, etc. New types of biomedical tests have appeared, in particular, enzyme immunoassay, which can be used to determine the presence of diseases such as AIDS and hepatitis; the use of new chemistry methods and increased sensitivity of old methods now makes it possible to determine many important substances without violating the integrity of the patient’s skin, one drop of saliva, sweat or other biological fluid.
So, what do all the above sciences, which are different branches of physical and chemical biology, do?
The basis of the chemistry of natural compounds was traditional organic chemistry, which was initially considered as the chemistry of substances found in living nature. Modern organic chemistry deals with all compounds that have carbon chains (or substituted with carbon heteroanalogs), and bioorganic chemistry, which studies natural compounds, has become a separate branch of science. The chemistry of natural compounds arose in the middle of the 19th century, when some fats, sugars and amino acids were synthesized (this is associated with the works of M. Berthelot, F. Wehler, A. Butlerov, F. Kekule, etc.).
The first protein-like polypeptides were created at the beginning of this century, at which time E. Fischer, together with other researchers, contributed to the study of sugars. The development of research on the chemistry of natural substances continued at an increasing pace until the middle of the 20th century. Following alkaloids, terpenes and vitamins, this science began to study steroids, growth substances, antibiotics, prostaglandins and other low-molecular bioregulators. Along with them, the chemistry of natural compounds studies biopolymers and biooligomers (nucleic acids, proteins, nucleoproteins, glycoproteins, lipoproteins, glycolipids, etc.). The main arsenal of research methods consists of methods of organic chemistry, but a variety of physical, physicochemical, mathematical and biological methods are also actively used to solve structural and functional problems. The main problems solved by the chemistry of natural compounds are:
a) isolation of the studied compounds in an individual state using crystallization, distillation, various types of chromatography, electrophoresis, ultrafiltration, ultracentrifugation, countercurrent distribution, etc.;
b) establishment of the structure, including spatial structure, based on approaches of organic and physical organic chemistry using mass spectroscopy, various types of optical spectroscopy (IR, UV, laser, etc.), X-ray diffraction analysis of nuclear magnetic resonance, electron paramagnetic resonance, optical dispersion rotation and circular dichroism, fast kinetics methods, etc.;
c) chemical synthesis and chemical modification of the studied compounds, including complete synthesis, synthesis of analogues and derivatives, in order to confirm the structure, clarify the relationship between structure and biological function, and obtain drugs valuable for practical use;
d) biological testing of the obtained compounds in vitro and in vivo.
The largest achievements in the chemistry of natural compounds were the decoding of the structure and synthesis of biologically important alkaloids, steroids and vitamins, the complete chemical synthesis of some peptides, prostaglandins, penicillins, vitamins, chlorophyll and other compounds; the structures of many proteins, the nucleotide sequences of many genes, etc. have been established. and so on.
The emergence of the science of biochemistry is usually associated with the discovery of the phenomenon of enzymatic catalysis and the biological enzyme catalysts themselves, the first of which were identified and isolated in a crystalline state in the 20s of the twentieth century. Biochemistry studies chemical processes occurring directly in living organisms and uses chemical methods in the study of biological processes. The major events in biochemistry were the establishment of the central role of ATP in energy metabolism, the elucidation of the chemical mechanisms of photosynthesis, respiration and muscle contraction, the discovery of transamination, the establishment of the mechanism of transport of substances through biological membranes, etc.
Molecular biology arose in the early 50s, when J. Watson and F. Crick deciphered the structure of DNA, which made it possible to begin studying the ways of storing and implementing hereditary information.
The greatest achievements of molecular biology are the discovery of the genetic code, the mechanism of protein biosynthesis in ribosomes, and the basis for the functioning of the oxygen carrier hemoglobin.
The next step on this path was the emergence of molecular genetics, which studies the mechanisms of operation of units of hereditary information of genes at the molecular level. One of the most pressing problems of molecular genetics is the establishment of pathways for regulating gene expression: transferring a gene from an active state to an inactive state and vice versa; regulation of transcription and translation processes. A practical application of molecular genetics was the development of methods of genetic engineering and gene therapy, which make it possible to modify the hereditary information stored in a living cell in such a way that the necessary substances will be synthesized inside the cell itself, which makes it possible to obtain many valuable compounds biotechnologically, as well as normalize the balance of substances, disrupted during illness. The essence of genetic engineering is the cutting of a DNA molecule into separate fragments, which is achieved with the help of enzymes and chemical reagents, followed by connection; This operation is performed with the aim of inserting into an evolutionarily adjusted chain of nucleotides a new fragment of a gene responsible for the synthesis of the substance we need, together with the so-called regulators of DNA sections that ensure the activity of “their” gene. Already now, with the help of genetic engineering, many drugs are produced, mainly of a protein nature: insulin, interferon, somatotropin, etc.
Chapter 2. ELECTIVE COURSE “CHEMISTRY AND MEDICINE”
chemistry medicine course training
In our information age - the age of modernization of biological and chemical education, oddly enough, schoolchildren have rather meager knowledge about their body, ways to maintain health and get out of situations when the body requires “repair”. To identify the reasons for the required “repair,” you need to know what the human body is like from the point of view of chemistry and biology, what underlies the preservation and maintenance of health, how to help your body cope with colds, and what is better to use: medicinal or herbal preparations.
While studying this course, concepts about health, components and indicators of health, factors that determine health (heredity, food, quality of environment, lifestyle), medications and their effect on the body, and their correct use are formed. It is always necessary to remember that “the dose can kill and the dose can cure.”
The course “Chemistry and Medicine” allows you to immerse yourself in a system of questions in biology and chemistry: the chemical properties of metals and non-metals, chemical reactions, cell chemistry, food, heredity of the body.
Life is based on chemical processes, and diseases are the result of their disruption in the body, which is a large retort.
T. Paracelsus
Everything is poison, nothing is poisonous, and everything is medicine. Only the dose makes a medicine a poison or a medicine.
T. Paracelsus
Life is the eternal movement of fluids between cells and within cells. Stopping this movement results in death. Partial slowing down of this movement in some organ causes partial disorder. A general slowdown in the movement of extracellular fluids causes disease.
Doctor A.S. Zalmanov, “Secret Wisdom”
I don’t walk in the steppe - I walk around the pharmacy, sorting through its herbal file cabinet. Boundless steppe, Endless steppe, You are a strange recipe written by nature.
S. Kirsanov
There is nothing else in nature, neither here nor there in the depths of space: Everything - from small grains of sand to planets - consists of single elements.
S. Shchipachev
What medicine cannot cure, iron can cure; what iron cannot cure, fire can cure.
Hippocrates
Course objectives.
1. Expand students’ knowledge about the body as a chemical factory.
2. Continue to develop students’ understanding of the importance of maintaining health at the biological and chemical level.
3. To develop elementary medicine skills in students.
Course objectives.
1. Update and expand students’ knowledge on health issues.
2. Teach schoolchildren to analyze lifestyle from the point of view of its impact on health.
3. Develop students’ skills in assessing the functional state of their body.
4. Provide vocational guidance to high school students.
Course structure and content (34 hours)
| Class | Number of hours | Topicsclasses | Kind of activity |
| Introduction to the course “Chemistry and Medicine” (24 hours) |
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| 1, 2 | 2 | Why do you need to treat your body? | Lecture |
| Chemistry and health (12 hours) |
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| 3 | 1 | Factors influencing human health | Conversation |
| 45 | 2 | Health formula | Lecture, conversation |
| 6 | 1 | Chemical elements and vital functions of the body | Lecture |
| 7, 8 | 2 | Why we eat and what we eat. Nutrition and disease. Food allergies | Conversation |
| 91011 | 3 | Diseases caused by a lack of chemical elements in the body | Lecture, conversation. Student messages |
| 12 | 1 | There is a time for everything (the body’s need for chemical elements at different stages of development) | Lecture |
| 13 | 1 | Where do toxic substances “linger”? | Lecture |
| 14 | 1 | Diseases and blood groups | "Round table" |
| Mirror of the body (4 hours) |
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| 15 | 1 | Leather. Characteristics and types of skin. Skin diseases | Student performances |
| 16 | 1 | Teeth are an indicator of internal problems of the body. Dental diseases | Lecture |
| 17 | 1 | At the dentist's appointment | Role-playing game |
| 18 | 1 | Medicine and cosmetology | "Round table" |
| Chemistry and medicine (9 hours) |
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| 19 | 1 | Development of medicine, stages of formation | Lecture |
| 20 | 1 | Medicines. Drug discovery and dosage forms | Lecture |
| 2122 | 2 | Classification of drugs | Lecture |
| 23 | 1 | Medicines and herbal preparations | Lecture |
| 24 | 1 | Aspirin, streptocide: chemical composition, route and effect in the body | Lecture |
| 25 | 1 | Medicines for the cardiovascular system | Lecture |
| 26 | 1 | Antibiotics and their effect on the body | Lecture |
| 27 | 1 | The body's dependence on drugs | Discussion |
| Biologically active compounds (4 h) |
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| 28 | 1 | Vitamins. Classification, effect of vitamins on the body. Diseases caused by deficiency or excess of vitamins | Conversation. Student messages |
| 29 | 1 | Enzymes, their classification, role in the body. The importance of enzymes | Lecture |
| 30 | 1 | Hormones. The importance of hormones. Diseases caused by a lack or excess of hormones in the body. Hormonal drugs | Lecture |
| 31 | 1 | Metabolic processes in the body. The role of water-salt metabolism in the life of the body | Lecture with elements of conversation |
| Gene diseases in humans (3 hours) |
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| 32 | 1 | Human gene program | Lecture |
| 33 | 1 | Diseases with a hereditary predisposition | Lecture |
| 34 | 1 | Social environment and man | Conversation |
an example is an ointment or emulsion of benzyl benzoate - an ester of benzoic acid and benzyl alcohol C 6 H 5 – C (O) – O – CH 2 – C 6 H 5.
Unfortunately, these drugs cause allergies in many patients, so old methods of treatment based on the use of elemental sulfur in the form of ointments on Vaseline are still relevant. But M.P. Demyanovich’s method is much more effective, although labor-intensive. When treating using this method, a 60% aqueous solution of sodium thiosulfate is rubbed into the skin for 10–15 minutes. After the skin has dried and crystals have appeared on it, rub a 6% aqueous solution of hydrochloric acid for 10–15 minutes. You are allowed to wash after three days. By this time the patient is recovering.
How can you explain the essence of Demjanovich's method from a chemist's point of view?
Note. When completing this task, it is advisable to discuss the problems of preventing scabies. This is an extremely contagious disease that is transmitted not only through direct contact with the patient, but also through his personal belongings - clothes, towels, and also through paper money. The best way to protect yourself from scabies is to strictly follow the rules of personal hygiene.
Task 3. In the book by M.M. Gurvich “Home Dietetics” for those suffering from urolithiasis provides the following recommendation: “The diet includes those varieties of greens and vegetables that are considered low in calcium and alkaline valencies: peas, Brussels sprouts, pumpkin.” Comment on this formulation from the position of a chemist, and if you can, also an agronomist.
Task 4. For the treatment of anemia (low hemoglobin content in the blood), iron preparations have long been used, including iron(II) sulfate, and sometimes reduced iron powder. There is also an old folk recipe for anemia - the “iron apple”: several nails are stuck into an apple (preferably the Antonovka variety) and left for a day. Then the nails are removed, and the apple is eaten by the patient.
How can you explain the effectiveness of the "iron apple" from a chemist's point of view?
Task 5. Herbal treatment is becoming increasingly popular, but most people do not strictly follow the rules for preparing decoctions and infusions, especially the dosage of raw materials, although this is very important when treating with this method. Most herbs are recommended to be brewed in the following proportion: 20 g (one full tablespoon) of dry crushed herbs per glass (200 ml) of boiling water, i.e. the ratio of mass parts is 1:10. In the summer, you can prepare preparations not from dried, but from freshly picked herbs. How to correctly calculate the ratio of herb and water in order to obtain an infusion of the same concentration?
Note. The moisture content of properly dried grass is 8–15%; in freshly picked plants, depending on their type, the water content ranges from 70 to 95%.
Task 6. To reduce the acidity of gastric juice and reduce its enzymatic activity in case of gastric ulcer and duodenal ulcer, gastritis with high acidity, doctors have such drugs as becarbonate in their arsenal (one tablet contains dry belladonna extract 0.01 g and sodium bicarbonate 0. 3 g), magnesium oxide MgO, white magnesia Mg(OH) 2 4MgCO 3 H 2 O, vicalin (which includes BiNO 3 (OH) 2, Mg(OH) 2 4MgCO 3 H 2 O, NaHCO 3), hydroxide aluminum (in the form of an amorphous white powder), almagel (a mixture of specially prepared Al (OH) 3 gel with MgO and sorbitol).
Many patients still, in the absence of these medications, use regular baking soda to get rid of heartburn (which doctors do not recommend doing!). Try to compare the mechanism of action of all these drugs and explain what advantages each of them has. Why do doctors now prefer drugs based on Al(OH) 3 and do not recommend taking soda to neutralize excess acidity of gastric juice?
Task 7. Professional athletes usually carry emergency medications with them for minor injuries (for example, a sprained ankle). Ethyl chloride C 2 H 5 Cl in ampoules or a set of two sealed bags is often used as such preparations: one contains dry NH 4 NO 3, the other contains water. Both drugs act in the same way: they cause rapid cooling of the damaged joint - this relieves pain and swelling. However, from a chemist's point of view, their actions are fundamentally different. Try to explain what the difference is.
Hint: the boiling point of ethyl chloride is 12–16 °C.
Task 8. Many people know the method of treating a runny nose or radiculitis using table salt. It is heated in a frying pan or in the oven, poured into a bag made of thick fabric, and the bag is applied to the sore spot for several hours.
What properties of table salt are used in this recipe? By the way, instead of salt, you can use clean sand, which, as is known, consists mainly of SiO 2.
Task 9. An advertisement for the medicinal and cosmetic cream “Ksenia” talks about the property of this cream to restore the salt balance in muscle and bone tissues. Among others, the text contains the following phrase: “Meanwhile, “Ksenia” washes your bones, clarifying her relationship with calcium, that is, lime, and makes you a berry in the full sense of the word. If you use “Xenia”, you are not at risk of deposition of calcium salts in the aorta, heart and kidneys. You will avoid osteochondrosis, soft tissue calcification, osteoporosis...” What in this text can cause an objection from a chemist?
Comment on this phrase from the point of view of a chemist.
Task 10. Caries has become a real scourge of the Russian population. According to statistics, more than 96% of the population suffers from it. One of the preventive measures is careful dental care. It is advisable to brush them after each meal. But there is one exception - if you have eaten sour berries or fruits, it is better not to brush your teeth for an hour, especially with a hard brush. Why?
Hint: the chemical composition of tooth enamel is close to the composition of the mineral hydroxylapatite Ca 5 OH (PO 4) 3.
Task 11. Calcium plays an important role in the life of the body. Calcium ions are necessary for the transmission of nerve impulses, contraction of skeletal muscles and heart muscles, formation of bone tissue, and blood clotting. Calcium preparations are widely used, in particular, in the treatment of fractures and increased release of calcium from the body, which occurs in long-term patients. Doctors have several calcium preparations in their arsenal. The most commonly used are calcium gluconate, lactate and glycerophosphate in tablet form. These drugs are similar in their effect on the body, so doctors often recommend purchasing any of them, leaving the right of choice to the patient.
Which drug is more rational to choose from the above, if their price is approximately the same?
Answers and solutions
1. Yes, this drug can be used without risk to health. The white precipitate is calcium carbonate CaCO 3, which was formed as a result of the interaction of CaCl 2 with air CO 2. A small amount of CaCO 3 is absolutely harmless.
It should be remembered that the case we described is still an exception to the general rule - most medications cannot be used after the expiration date indicated on the packaging, since most of them are organic compounds of complex composition and their decomposition products can be toxic .
2. When a solution of sodium thiosulfate is acidified, thiosulfuric acid is formed:
Na 2 S 2 O 3 + 2HCl = H 2 S 2 O 3 + 2NaCl.
Thiosulfuric acid quickly decomposes, releasing sulfur and sulfur dioxide:
H 2 S 2 O 3 = S + H 2 O + SO 2.
At the moment of release, sulfur has a particularly active effect on the scabies mite; SO 2 has a similar effect, which is why Demyanovich’s method gives such good results.
3. For a chemist, the phrase “alkaline valencies” causes bewilderment. Valence is the ability of an atom to attach or replace a certain number of other atoms or atomic groups to form a chemical bond. But what the author meant by “alkaline valences” can only be guessed at. If you use a reference book that lists the chemical composition of plant products, you will find that vegetables, along with calcium, also contain potassium, sodium, rubidium, lithium, i.e., alkali metals. It can be assumed that the author calls them “alkaline valences”.
The cause of urolithiasis is a violation of salt metabolism in the body, therefore the mineral composition of food is very important for the patient, who needs to monitor the content of all minerals in his diet, including alkali metals.
More correctly, from the point of view of a chemist, this advice should be formulated as follows: “Include in the diet those greens and vegetables that are poor in calcium and alkali metals.” There is a wording in the text that is also incorrect from a biologist’s point of view: the term “variety” should be replaced by the term “species” or “culture”.
4. Iron is used to treat anemia, since it is part of hemoglobin. Apples are recommended for such patients because they contain more iron than other fruits (on average 2200 mg per 100 g of product). The iron in the alloy from which nails are made dissolves, albeit slowly, in the organic acids contained in the apple. The apple is enriched with iron even more. It is believed that of all apple varieties, Antonovka contains the most iron; it also contains a lot of acids, which facilitates the dissolution of iron.
5. Let us take for calculation the arithmetic average values of moisture content in plants:
(70 + 95)/2 = 82.5% – fresh,
(8 + 15)/2 = 11.5% – dry.
To prepare one glass of infusion, you need to take 20 g of dried raw materials and 200 g of water. If the mass fraction of water in dried raw materials is 11.5%, then the content of dry plant material is (100–11.5) = 88.5%. Then
Information density, which is very important for the development of modern technical means of recording, accumulating and storing information. 7. The most important discoveries in chemistry of the XXI century 2001 William Knowles, Ryoji Noyori and Barry Sharpless “For research used in the pharmaceutical industry - the creation of chiral catalysts for redox reactions.” 2002 John Fenn and Koichi Tanaka "For...
Only in position 4. The formation of other products (X, XI, XII, XIV and XV) is clear from the diagram. Estrogenic hormones are inherent in animal organisms, but they are also found in plants, for example estrone, in coconut extract and in female willow flowers. At first, when the chemistry of steroid estrogens was not sufficiently developed, various drugs were used: folliculin - an aqueous solution obtained from purified ...
Chemistry answers!
Chemistry subject. Chemistry and environment. The connection between chemistry and medicine.
Chemistry subject. Chemistry and Environment
Let's look around. We ourselves and everything that surrounds us consists of substances. There are a lot of substances. Currently, scientists know about 10 million organic and about 100 thousand inorganic substances. And they are all characterized by certain properties. The properties of a substance are the characteristics by which substances differ from each other or are similar to each other.
Each individual type of matter that, under given conditions, has certain physical properties, for example, aluminum, sulfur, water, oxygen, is called a substance.
Chemistry studies the composition, structure, properties and transformation of substances. A deep knowledge of chemistry is absolutely necessary for specialists in all sectors of the national economy. Along with physics and mathematics, it forms the basis for the training of highly qualified specialists.
Various changes occur with substances, for example: evaporation of water, melting of glass, combustion of fuel, rusting of metals, etc. These changes with substances can be attributed to physical or chemical phenomena.
Physical phenomena are those in which these substances do not transform into others, but usually only their state of aggregation or form changes.
Chemical phenomena are those phenomena that result in the formation of other substances from given substances. Chemical phenomena are called chemical transformations or chemical reactions
In chemical reactions, starting substances are transformed into other substances that have different properties. This can be judged by the external signs of chemical reactions: 1) release of heat (sometimes light); 2) color change; 3) the appearance of odor; 4) formation of sediment; 5) gas release.
Molecules and crystals are made up of atoms. Each individual type of atom is called a chemical element.
In total, the existence of (92) different chemical elements has been established in nature (on Earth). Another 22 elements were obtained artificially using nuclear reactors and powerful accelerators.
All substances are divided into simple and complex.
Substances that consist of atoms of one element are called simple.
Sulfur S, hydrogen H2, oxygen O2, ozone O3, phosphorus P, iron Fe are simple substances.
Substances that consist of atoms of different elements are called complex.
For example, water H2O consists of atoms of different elements - hydrogen H and oxygen O; chalk CaCO3 consists of atoms of the elements calcium Ca, carbon C and oxygen O. Water and chalk are complex substances.
The concept of “simple substance” cannot be identified with the concept of “chemical element”. A simple substance is characterized by a certain density, solubility, boiling and melting points, etc. A chemical element is characterized by a certain positive nuclear charge (ordinal number), oxidation state, isotopic composition, etc. The properties of an element relate to its individual atoms. Complex substances are not made up of simple substances, but from elements. For example, water does not consist of the simple substances hydrogen and oxygen, but of the elements hydrogen and oxygen.
The names of the elements coincide with the names of their corresponding simple substances, with the exception of carbon.
Many chemical elements form several simple substances that differ in structure and properties. This phenomenon is called allotropy, and the resulting substances are allotropic modifications or modifications. Thus, the element oxygen forms two allotropic modifications: oxygen and ozone; element carbon - three: diamond, graphite and carbine; Several modifications form the element phosphorus.
The phenomenon of allotropy is caused by two reasons: 1) a different number of atoms in the molecule, for example oxygen O2 and ozone O3; 2) the formation of various crystalline forms, such as diamond, graphite and carbine.
Chemistry and medicine
Chemistry should help medicine in the fight against disease. However, these sciences went through a long and difficult path of development before they managed to achieve success in solving common problems.
In the Middle Ages, alchemists repeatedly made attempts to intervene in medicine, and often the doctor and the chemist were combined in one person. However, alchemical theories could not be of benefit to practical medicine, since they were not based on experience, but on biased and false statements and, as a rule, led to errors. Thus, the legendary chemist and doctor, Vasily Valentin, who wrote a book about antimony (“the triumphal chariot of antimony”), proposed it to get rid of all diseases. This element, an analogue of arsenic, could bring nothing but harm to the suffering. The random luck of chemists and the use of folk experience still helped doctors, and contacts between them and chemists were never interrupted. In the 15th century Theophrastus Paracelsus refuted the doctrine of pneumas, but immediately replaced them with the no less mysterious “archaeus,” which does not have a material nature, but subjugates matter. These fantastic “theories” were soon forgotten, but Paracelsus’ practical medical activity turned out to be productive. He investigated compounds of mercury and arsenic and laid the foundation for iatrochemistry - the science of using certain chemical compounds to treat diseases. True, Paracelsus’s recipes would cause modern doctors more fear than admiration, but still these were steps along the right path, which could really lead to success and led to it four hundred years later. The history of medicine has preserved an inventory of “all sorts of potions” brought to Moscow in 1602. English pharmacist James French on behalf of Queen Elizabeth. Among the “potions” are: “candied apples, damasen plums, citron juice cheese, cinnamon vodka, juniper vodka, pyrethrum, galangal, aloe, opium” and even “Armenian clay”; There are also substances of animal origin, for example “deer antler”. There are 171 drugs in total. Some of them were certainly beneficial, in particular, “citron juice”, i.e. lemon juice, galangal, aloe, which are still used in medicine.
Chemistry has invaded human life since ancient times and continues to provide him with diverse assistance even now. Organic chemistry is especially important, considering organic compounds - saturated, unsaturated cyclic, aromatic and heterocyclic. Thus, on the basis of unsaturated compounds, important types of plastics, chemical fibers, synthetic rubbers, compounds with low molecular weight - ethyl alcohol, acetic acid, glycerin, acetone and others are obtained, many of which are used in medicine. Back in the mid-19th century, the production of medicines in the world was concentrated in isolated pharmacies, in which pharmacists prepared drugs according to recipes known only to them, passed down by inheritance. At that time, alternative medicine played a major role. The raw materials for the synthesis of organic drugs are natural gas, oil, coal, shale and wood. Oil and gas are a valuable source of raw materials for the synthesis of hydrocarbons, which are intermediate products in the production of organic substances and medicines. Petroleum jelly, petroleum jelly, and paraffin obtained from petroleum are used in medical practice. This is exactly how, by chemical modification of natural penicillin, many of its semi-synthetic analogues, for example oxacillin, were obtained.
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Creation date: 2014/03/24
Fluorine in the form of fluorapatite Ca5(PO4)3F is found in teeth and bones, and also in the form of compounds (NaF, SnF2) is included in toothpastes.
Chlorine NaCl is one of the main components of blood plasma; a NaCl solution with a mass fraction of 0.9% (saline) is used for injection.
Solution hydrochloric acid used to treat diseases of the gastrointestinal tract (gastritis, pancreatitis). Hydrochloric acid performs bactericidal functions in the stomach and intestines; in addition, it participates in the reduction reactions of Fe3+ ions to Fe2+, and thus iron ions supplied to the body with food become available for absorption and participate in the formation of hemoglobin and other biologically active compounds.
Bromine necessary for the production of various medicinal substances. For example, sodium bromide and potassium bromide are used orally to restore the correct ratio of excitation and inhibition processes in the brain.
Iodine used in medicine in the form of the so-called iodine tincture (10% solution of iodine in ethyl alcohol), an excellent antiseptic and hemostatic agent. Iodine is involved in the formation of thyroid hormone, which affects the metabolism in the body and the activity of the nervous system.
Sodium iodide and potassium iodide used for the prevention and treatment of endemic goiter, for the prevention of atherosclerosis.
Oxygen widely used in medical practice in the treatment of pulmonary and cardiac diseases, to support the life of patients with difficulty breathing (oxygen pillows, pressure chambers, “oxygen cocktail”). Oxygen is used in oxygen-breathing apparatus (on military submarines, during high-altitude flights of military pilots, during underwater work).
Ozone(allotropic modification of oxygen) is a strong oxidizing agent that exhibits disinfectant and bactericidal properties. In small doses (in existing natural conditions 1.10-6% by volume in the air), ozone has a stimulating effect on the human body: it increases resistance to toxic substances, the level of hemoglobin in the blood, immunobiological protection, improves lung function, and normalizes blood pressure. 90% of ozone is concentrated in the air at an altitude of 10-50 km. Ozone saves humans and animals from blindness by absorbing excess ultraviolet rays that have a harmful effect on the retina. In high concentrations, ozone is toxic, has a pronounced irritant effect on the upper respiratory tract, bronchi and lungs, delays the synthesis of vitamins D, causes a feeling of fatigue, headache, inflammation of the mucous membranes of the eyes, nose, and nosebleeds.
Hydrogen sulfide water(a solution of hydrogen sulfide in water) is used in medicine to treat rheumatism and skin diseases; is one of the components of mineral waters.
Widely used in medicine sulfuric acid salts: Na2SO4.10H2O (Glauber's salt) and MgSO4.7H2O (bitter salt) - as a laxative; CaSO4.2H2O (gypsum) - plaster casts; CuSO4.5H2O (copper sulfate) is an astringent and antiseptic.
Nitrogen used in medicine as a coolant in cryotherapy.
10% aqueous ammonia solution(ammonia) is used as a medicine for fainting. The ammonia gas released from the solution irritates the nerve endings of the upper respiratory tract and reflexively excites the central nervous system - the victim regains consciousness. It is also recommended to inhale ammonia in case of poisoning with certain gaseous toxic substances.
Ammonium chloride- diuretic and expectorant.
Silver nitrate(lapis), along with antimicrobial properties, has an astringent effect in small concentrations (up to 2%), and a cauterizing effect in large concentrations (5% or more). It is used to treat skin ulcers, as well as for lesions of the mucous membranes of the eye (conjunctivitis) and larynx (laryngitis); used to cauterize warts.
Nitric oxide (I) (N2O)- “laughing gas” is used as an anesthetic mixed with oxygen (80% N2O and 20% O2) for gas anesthesia.
Phosphorus(element) is part of the teeth, bones, muscles, nerve tissue and brain. Participates in the transfer of energy in the body (ATP), hereditary information (DNA and RNA), and maintaining a constant blood acidity. Phosphorus is used in pharmacy to make medicines (phosphacol - for glaucoma).
Solution baking soda used to eliminate heartburn caused by increased acidity of gastric juice, as well as in case of poisoning in a chemical laboratory with acids. In this case, the solution of baking soda, as a result of hydrolysis of the salt, has an alkaline environment and eliminates excess acid in the stomach.
Coal activated is prescribed orally 20-30 g in the form of a suspension in water for poisoning with salts of heavy metals, food intoxication. By adsorbing toxic substances, activated carbon prevents their absorption in the gastrointestinal tract and the manifestation of their toxic effects. Activated carbon tablets are prescribed orally for flatulence (gas in the intestines) and digestive disorders.
Mixture carbon dioxide(5%) with oxygen or air (carbogen) is a means of stimulating the respiratory center and is used in medicine in cases of severe respiratory depression. Carbon dioxide is also used as a cooling agent (“dry ice”).
Calcium carbonate used in tooth powders and pastes.
Sodium and potassium ions play a vital role in the life of the human body. Sodium is involved in the transmission of nerve impulses and promotes water retention in tissues.
Sodium sulfate used for poisoning with barium and lead salts.
Lithium salts used to treat mental illnesses (lithium carbonate Li2CO3), as well as diseases associated with salt deposition, such as gout.
Potassium chloride It is used orally in the form of a 10% solution as an antiarrhythmic agent to regulate cardiac activity.
Calcium is part of the bones. With its deficiency, growth disturbance and curvature of the skeletal bones occur.
Calcium chloride It is used to treat neuroses, and also as an antiallergic, decongestant, and anti-inflammatory drug. It is prescribed orally or intravenously.
Magnesium sulfate(MgSO4) reduces vascular spasms, is used as a laxative and choleretic agent.
Barium sulfate(BaSO4) is used as a radiocontrast agent for X-ray examination of the gastrointestinal tract.
Aluminum acetate(Al(CH3COO)3), potassium alum (KAl(SO4). 12H2O) are used in medicine to treat skin diseases.
Aluminum hydroxide is part of an adsorbent and enveloping agent used for stomach ulcers and gastritis. (For example, the drug Almagel).
Manganese refers to biometals. It affects hematopoietic processes; accelerates the formation of antibodies that neutralize the harmful effects of foreign proteins. For example, an intravenous injection of manganese sulfate protects against a karakurt spider bite.
Potassium permanganate(KMnO4) is used in medicine as a disinfectant, antiseptic and hemostatic agent.
Zinc sulfate(ZnSO4) as an antiseptic is included in the composition of eye drops; zinc oxide(ZnO) is used as an astringent, drying agent and disinfectant for skin diseases.