Soaps in Daily Life.

Soaps have been used for thousands of years as part of religious ceremonies and daily life. Derived from fatty acids or triglycerides (fats or oils) into their alkali derivatives through a process called saponification, soaps are important for healthcare professionals in preventing the spread of disease. Partly due to their alkaline nature, soaps are limited by their irritancy to the skin and their tendency to form insoluble and inactive salts when combined with either hard water or sea water. Therefore, soap alternatives or synthetic detergents have been developed. Detergents are classified into four groups: anionic, cationic, amphoteric, and non-ionic. These four groups are based on the hydrophilic qualities and surfactants they possess. Each group has characteristics that pertain to its main uses, irritancy, and toxicity. Understanding soaps and detergents may assist clinicians in making intelligent choices when using these agents on their patients as either skin cleansers or wound cleansers. Understanding the characteristics of soaps and detergents is especially important when dealing with at-risk patients such as the elderly. Soaps Soaps are cleaning agents that are usually made by reacting alkali (e.g., sodium hydroxide) with naturally occurring fat or fatty acids. The reaction produces sodium salts of these fatty acids, which improve the cleaning process by making water better able to lift away greasy stains from skin, hair, clothes, and just about anything else. As a substance that has helped clean bodies as well as possessions, soap has been remarkably useful.  Anionic Surfactant An anionic surfactant is a macromolecule, usually in the sulfonate or sulfate group of chemicals such as sodium laureth sulfate, that acts as an active surface agent to lower the surface tension of liquids. This allows them to bind to impurities and particles that are suspended in the liquid, which makes them effective cleaning agents in water. In small concentrations, they can also cause the foaming of compounds in water by creating large numbers of small bubbles of gas, and this makes them effective in cosmetics such as shampoo, toothpaste, and in fire-suppressing agents. Basic soap used to clean the human body is also a type of surfactant or detergent made from natural fatty acids of plant or animal origin. The difference with an anionic surfactant is that it is largely a synthetic chemical, and it has been designed to act not only as a surfactant that binds to oils and particulates in water, but also as a denaturing chemical for proteins. Since anionicsurfactants break down proteins attached to clothing in water, they are not recommended for ordinary soap use, as human skin is also a type of protein. Chemistry of Soap The basic structure of all soaps is essentially the same, consisting of a long hydrophobic (water-fearing) hydrocarbon "tail" and a hydrophilic (waterloving) anionic "head": CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 COO − or CH 3 (CH 2 ) n COO − The length of the hydrocarbon chain ("n") varies with the type of fat or oil but is usually quite long. The anionic charge on the carboxylate head is usually balanced by either a positively charged potassium (K + ) or sodium (Na + ) cation. In making soap, triglycerides in fat or oils are heated in the presence of a strong alkali base such as sodium hydroxide, producing three molecules of soap for every molecule of glycerol. This process is called saponification. Like synthetic detergents, soaps are "surface active" substances ( surfactants ) and as such make water better at cleaning surfaces. Water, although a good general solvent, is unfortunately also a substance with a very high surface tension. Because of this, water molecules generally prefer to stay together rather than to wet other surfaces. Surfactants work by reducing the surface tension of water, allowing the water molecules to better wet the surface and thus increase water's ability to dissolve dirty, oily stains. In studying how soap works, it is useful to consider a general rule of nature: "like dissolves like." The nonpolar hydrophobic tails of soap are lipophilic ("oil-loving") and so will embed into the grease and oils that help dirt and stains adhere to surfaces. The hydrophilic heads, however, remain surrounded by the water molecules to which they are attracted. As more and more soap molecules embed into a greasy stain, they eventually surround and isolate little particles of the grease and form structures called micelles that are lifted into solution. In a micelle, the tails of the soap molecules are oriented toward and into the grease, while the heads face outward into the water, resulting in an emulsion of soapy grease particles suspended in the water. With agitation, the micelles are dispersed into the water and removed from the previously dirty surface. In essence, soap molecules partially dissolve the greasy stain to form the emulsion that is kept suspended in water until it can be rinsed away. As good as soaps are, they are not perfect. For example, they do not work well in hard water containing calcium and magnesium ions, because the calcium and magnesium salts of soap are insoluble; they tend to bind to the calcium and magnesium ions, eventually precipitating and falling out of solution. In doing so, soaps actually dirty the surfaces they were designed to clean. Thus soaps have been largely replaced in modern cleaning solutions by synthetic detergents that have a sulfonate (R-SO 3 − ) group instead of the carboxylate head (R-COO − ). Sulfonate detergents tend not to precipitate with calcium or magnesium ions and are generally more soluble in water. Soap in cleaning Soap is an excellent cleanser because of its ability to act as an emulsifying agent. An emulsifier is capable of dispersing one liquid into another immiscible liquid. This means that while oil (which attracts dirt) doesn't naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed. The organic part of a natural soap is a negatively-charged, polar molecule. Its hydrophilic (water-loving) carboxylate group (-CO2) interacts with water molecules via ion-dipole interactions and hydrogen bonding. The hydrophobic (water-fearing) part of a soap molecule, its long, nonpolar hydrocarbon chain, does not interact with water molecules. The hydrocarbon chains are attracted to each other by dispersion forces and cluster together, forming structures called micelles. In these micelles, the carboxylate groups form a negatively-charged spherical surface, with the hydrocarbon chains inside the sphere. Because they are negatively charged, soap micelles repel each other and remain dispersed in water. Grease and oil are nonpolar and insoluble in water. When soap and soiling oils are mixed, the nonpolar hydrocarbon portion of the micelles break up the nonpolar oil molecules. A different type of micelle then forms, with nonpolar soiling molecules in the center. Thus, grease and oil and the 'dirt' attached to them are caught inside the micelle and can be rinsed away.

Ester in Daily Life.

In our daily life, we use energy and we sweat. Sweating makes our body smell and thus, a superb creation is created, the perfume. Perfumes are known as esters.


Esters have a very sweet fruity smell.  Naturally occurring esters are found in fruits.  An ester is a product of the reaction of an acid (usually organic) and an alcohol (the hydrogen of the acid R-COOH is replaced by an alkyl group R').  Esters mainly result from the condensation (a reaction that produces water) of a carboxylic acid and an alcohol.  The process is called esterification.  This reaction can be catalyzed by the presence of H⁺ ions.  Sulphuric acid, H₂SO₄, is often used as a catalyst for this reaction.  The name ester is derived from the German Essig-Aether, an old name for acetic acid ethyl ester (ethyl acetate).  Esters have the general formula R-COOR',

Esters are named in the same manner as salts (although esters and salts have completely different properties): two-word names are used.  Note that in the general formula, R-COOR' (the carbon is double-bonded to one oxygen atom and single-bonded to another), the alkyl group (R') is always attached to an oxygen atom.  This alkyl group (R') is named as the first word of the two-word name.  The second word is derived by adding the ending -oate to the stem of the acid name (-oic in the acid name is replaced by -oate).
A reversible reaction between an alcohol and a carboxylic acid causes loss of water and the formation of an ester:

Alcohol + Carboxylic Acid  Ester + Water

R'OH + RCOOH  RCOOR' + H₂O.

Esters are named as derivatives of the carboxylic acid from which they are formed.   Condensation of ethanoic acid with methanol will produce methyl ethanoate.   As stated above the ending of the acid -oic is changed to -oate, much as if the ester were a salt of the acid.  The esterification reactions are generally easily reversible by addition of water; the reverse reaction is called the hydrolysis of the ester and proceeds in the presence of aqueous base.

Methyl ethanoate

CH₃OH + CH₃COOH  CH₃COOCH₃ + H₂O

methanol  + ethanoic acid  methyl ethanoate + water

The esterification process will proceed more nearly to completion if a substance which removes water without reacting with the acid or the alcohol is added to the reaction, such as sulfuric acid.   For example, the reaction between ethanoic acid and ethanol produces the ester ethyl ethanoate.

Ethyl ethanoate

CH₃COOH + CH₃CH₂OH  H₂SO₄  CH₃COOCH₂CH₃+ H₂O

ethanoic acid + ethanol  H₂SO₄  ethyl ethanoate + water

The concentrated H₂SO₄ removes water from the products and is a dehydrating agent.  Most esters have very pleasant odors (see below).  Many flavoring and scenting agents are made from esters.  Esters are volatile liquids which are not ionized and they are soluble in organic solvents but not in water.
The simplest ester is H-COO-CH₃ (methyl methanoate).

Methyl methanoate

In the laboratory, methyl methanoate can be produced by the condensation reaction of methanol  and methanoic acid, as follows:

HCOOH + CH₃OH  HCOOCH₃ + H₂O

methanoic acid + methanol  methyl methanoate + water

Industrial methyl methanoate, however, is usually produced by the combination of methanol and carbon monoxide in the presence of a strong base:

CH₃OH + CO  HCOOCH₃

methanol + carbon monoxide  methyl methanoate

As shown in the diagram above the hydrogen atom on the right can be replaced with a CH₃ group or additional CH₂ units, producing other methyl esters, such as:

Ethyl methanoate

For esters derived from the simplest carboxylic acids, the traditional names are recommended by IUPAC, such as, formate, acetate, propionate, butyrate, though out of these only acetate may carry further substituents.  For esters from higher acids, the alkane name with an -oate ending is generally preferred, e.g., hexanoate.   Common esters of aromatic acids include benzoates such as methyl benzoate, with substitution allowed in the name.
Common names of esters are derived from the organic acid and the alcohol from which they are derived.  For example, when acetic acid reacts with ethyl alcohol, the ester formed is called ethyl acetate.  The IUPAC name is different.  Acetic acid is called ethanoic acid by the IUPAC rules.  Thus the ester formed is called ethyl ethanoate.  IUPAC names ester from two words: first from the prefix of the alcohol and the second from the name of the acid.

ethyl alcohol + acetic acid  ethyl acetate + water (common names)

ethanol + ethanoic acid  ethyl ethanoate + water (IUPAC names)

(1)

General formula RCOOR'.  In the following example R is H- while R' is a methyl group -CH₃.  This will produce the simplest of esters.  The reaction of methanoic acid HCOOH and methanol CH₃OH can form this ester.  From the IUPAC rules, the ester will take its first name from the prefix of the alcohol, in this case methyl, and the second name from the acid, in this case it is methanoate.  Thus HCOOCH₃ is named methyl methanoate by the rules laid down for  IUPAC nomenclature for esters.  The common name of this ester is methyl formate.

methyl methanoate, methyl formate HCOOCH₃

formic acid + methyl alcohol  methyl formate + water (common names)

methanoic acid  + methanol  methyl methanoate + water (IUPAC names)

(2)
General formula RCOOR'.  In the following example R is H- while R' is an ethyl group -C₂H₅.  The reaction of methanoic acid HCOOH and ethanol C₂H₅OH can form this ester.  From the IUPAC rules, the ester will take its first name from the prefix of the alcohol, in this case ethyl, and the second name from the acid, in this case it is methanoate.  Thus HCOOC₂H₅ is named ethyl methanoate by the rules laid down for  IUPAC nomenclature for esters. The common name for this ester is ethyl formate.

ethyl methanoate, ethyl formate, HCOOC₂H₅

formic acid + ethyl alcohol  ethyl formate + water (common names)

methanoic acid + ethanol  ethyl methanoate + water (IUPAC names)

(3)

General formula RCOOR'.  In the following example R is CH₃- while R' is also a methyl group -CH₃.  The reaction of ethanoic acid CH₃COOH and methanol CH₃OH can form this ester.  From the IUPAC rules, the ester will take its first name from the prefix of the alcohol, in this case methyl, and the second name from the acid, in this case it is ethanoate.  Thus CH₃COOCH₃ is named methyl ethanoate by the rules laid down for  IUPAC nomenclature for esters.  The common name of this ester is methyl acetate.

methyl ethanoate, methyl acetate CH₃COOCH₃

acetic acid + methyl alcohol  methyl acetate + water (common names)

ethanoic acid + methanol  methyl ethanoate + water (IUPAC names)

(4)

General formula RCOOR'.  In the following example R is CH₃- while R' is an ethyl group -C₂H₅.  The reaction of ethanoic acid CH₃COOH and ethanol C₂H₅OH can form this ester.   From the IUPAC rules, the ester will take its first name from the prefix of the alcohol, in this case ethyl, and the second name from the acid, in this case it is ethanoate.  Thus CH₃COOC₂H₅ is named ethyl ethanoate by the rules laid down for  IUPAC nomenclature for esters. The common name of this ester is ethyl acetate.

ethyl ethanoate, ethyl acetate CH₃COOC₂H₅

acetic acid + ethyl alcohol  ethyl acetate + water (common names)

ethanoic acid + ethanol  ethyl ethanoate + water (IUPAC names)

(5)

General formula RCOOR'.  In the following example R is CH₃-CH₂- while R' is a methyl group -CH₃.  The reaction of propanoic acid CH₃CH₂COOH and methanol CH₃OH can form this ester.   From the IUPAC rules, the ester will take its first name from the prefix of the alcohol, in this case methyl, and the second name from the acid, in this case it is propanoate.  Thus CH₃CH₂COOCH₃ is named methyl propanoate by the rules laid down for  IUPAC nomenclature for esters.

CH₃CH₂COOH + CH₃OH  CH₃CH₂COOCH₃ and H₂O

Propanoic Acid + Methanol  Methyl Propanoate + Water

Many esters have distinctive odors, which has led to their use as artificial flavorings and fragrances. For example:

Drugs in Daily Life.

A drug is a chemical substance that has known biological effects on humans or other animals. 

The role played by organic chemistry in the pharmaceutical industry continues to be one of the main drivers in the drug discovery process. However, the precise nature of that role is undergoing a visible change, not only because of the new synthetic methods and technologies now available to the synthetic and medicinal chemist, but also in several key areas, particularly in drug metabolism and chemical toxicology, as chemists deal with the ever more rapid turnaround of testing data that influences their day-to-day decisions.

Antibiotics

Antibiotics are a group of medicines that are used to treat infections caused by bacteria and certain parasites. They are sometimes called antibacterials. Antibiotics can be taken by mouth as liquids, tablets, or capsules, or they can be given by injection. Usually, people who need to have an antibiotic by injection are in hospital because they have a severe infection. Antibiotics are also available as creams, ointments, or lotions to apply to the skin to treat certain skin infections.

It is important to remember that antibiotics only work against infections that are caused by bacteria and certain parasites. They do not work against infections that are caused by viruses (for example, the common cold or flu), or fungi (for example, thrush in the mouth or vagina), or fungal infections of the skin.

Occasionally, a viral infection or minor bacterial infection develops into a more serious secondary bacterial infection.

There are various antibiotics available and they come in various different brand names. Antibiotics are usually grouped together based on how they work. Each type of antibiotic only works against certain types of bacteria or parasites. This is why different antibiotics are used to treat different types of infection. The main types of antibiotics include:

·         Penicillins - for example, penicillin V, flucloxacillin, and amoxicillin.

·         Cephalosporins - for example, cefaclor, cefadroxil, cefalexin.

·         Tetracyclines - for example, tetracycline, doxycycline, and minocycline.

·         Aminoglycosides - for example, gentamicin, amikacin, and tobramycin.

·         Macrolides - for example, erythromycin, azithromycin, and clarithromycin.

·         Clindamycin.

·         Sulfonamides and trimethoprim - for example, co-trimoxazole.

·         Metronidazole and tinidazole.

·         Quinolones - for example, ciprofloxacin, levofloxacin, and norfloxacin.

Analgesics

Analgesics, also known as "painkillers", are medicines which relieve pain. Most analgesics are safe to use when taken as prescribed or instructed by your doctor or pharmacist, in conjunction with the manufacturer’s instructions on the packaging. Some extra precautions may apply to patients with pre-existing medical conditions such as kidney failure or gastric ulcers. 

This page outlines some commonly used over-the-counter analgesics, including what they are used for, possible side effects and risks associated with using them outside the directions on the packet. The painkillers covered are:

·         aspirin

·         codeine (in combination products)

·         ibuprofen

·         paracetamol.

Analgesics are available in many forms. These include tablets, capsules, suppositories, soluble powders and liquids. Analgesics are generally swallowed and their intended purpose is to relieve pain. Some can also be used to relieve fever, symptoms of cold and flu, reduce inflammation and swelling, control diarrhea and suppress coughing.