Quality Control and Preservation of Fragrances

If you want to make a perfume, mix 3ml of the above solution with 97ml of distilled water, stir well and filter.

Another preparation method is to use an intermediate to disperse the essential oil in water. Commonly used intermediates are: talc powder, kaolin, filter paper pulp, etc.

Essential oil 1g

Distilled water 1000ml

Talc powder 10g

Grind the talc powder with the essential oil. Then add water and stir well. Let stand for 24 hours, stirring occasionally. Then filter the solution through wet filter paper.

The solubility coefficient of essential oils in water is 0.05 corresponding to a concentration of 0.5g/l. In the above formula, excess essential oils must be used because water only dissolves the hydrophilic parts and very little dissolves the hydrophobic parts and terpene-like hydrocarbons present in essential oils. Here, talc powder plays the role of a dispersant. The perfume prepared by this method is often not clear because the essential oil particles or talc powder pass through the filter paper. In this case, the preparation must be filtered again. The disadvantage of this method is that talc powder absorbs a large amount of essential oil.

Although the perfumes prepared by this method do not have the pleasant aroma of those obtained by distillation, many Pharmacopoeias still prescribe this method because it ensures a defined concentration of essential oils and allows the preparation of small quantities of perfumes.

In recent years, tween-type surfactants have been increasingly used to dissolve essential oils in water when preparing perfumes. The formula for perfumes made from essential oils is as follows:

Essential oil 2g

Tween 20 20g

Ethanol 200ml

Distilled water 1000ml

Finished products prepared with tween as a dissolving medium have a stronger aroma, a defined concentration of essential oils and can be preserved longer.

4.4.3. Quality control and preservation of perfume

Fragrance water is usually clear, colorless, and has the distinctive smell of the medicinal herbs or essential oils used to prepare it. The density of fragrance water is approximately that of distilled water, with a neutral or slightly acidic pH.

Except for peach leaf water and cinnamon distilled water which have definite active ingredients, most other aromatic waters contain about 0.03% essential oil. Essential oil is determined by extraction or distillation.

Factors that decompose perfume are temperature, light, air, bacteria and mold. Under the effect of high temperature, part of the essential oil can evaporate, light and air oxidize the essential oil, making the perfume smell burnt and become more acidic. Bacteria and mold growing in perfume change the product's smell, taste and color.

The perfume should be stored in a colored glass bottle, tightly sealed, in a cool place. Nipagin can be added at a ratio of 0.05% for preservation.

4.4.4. Some examples

Peppermint water

Recipe: 100g fresh mint tops

Distilled water etc.

Chop the mint tops. Steam with scissors. Collect 100g of the finished product. If you don't have fresh mint, use dried mint, 20g of dried mint corresponds to 100g of fresh mint.

The finished product is a slightly cloudy liquid, minty smell, pleasant cool taste. 100ml of mint scented water contains 0.03 - 0.04 essential oil.

Peppermint water can be prepared by dissolving essential oils as follows: Peppermint essential oil 1.5g

Distilled water 100ml

Talc powder 15g

Grind peppermint essential oil with talc powder, then shake vigorously with boiled distilled water cooled to 40 - 50 0 C. Leave for 24 hours. Stir occasionally. Then filter through wet filter paper. The solution is clear or slightly cloudy, colorless, with a minty taste.

4.5. Potio

4.5.1. Definition, classification

Potio is a soft drink containing one or more medicinal ingredients, usually mixed according to prescription and taken by spoonful (10 - 15ml).

Potios are often found in prescription preparations, however the Pharmacopoeia also has some regulations on potio formulas such as: cinnamon tincture potio, antiemetic potio...

Potio can be divided into 3 types:

- Potio main name (potio solution)

- Potio mixture

- Potio emulsion

The solvent and carrier of potio are water and aromatic distilled water, infusion water or decoction of medicinal herbs. There are also cases where low-proof alcohol is used (cinnamon alcohol potio).

The pharmaceutical ingredients in potions are very diverse. They can be medicinal alcohols, medicinal extracts, chemicals that are easily soluble in water or slightly soluble in water, volatile chemicals (ether, ethanol, essential oils, etc.).

In addition, potions also contain sweeteners (simple syrup, medicinal syrup, or a mixture of syrups).

As mentioned, in the potio formulation there may be water-insoluble substances that must be dispersed in the form of a fine suspension or emulsion (potio emulsion).

Potio suspension, potio emulsion apply the methods of preparing suspension, emulsion will be stated in the chapter of suspension, emulsion.

4.5.2. Preparation techniques

Because the composition of the drugs is complex, it is difficult to propose a general preparation method. The following are just a few points to note when preparing these potio forms of drugs.

- If the potio contains medicinal alcohol or liquid extract, the medicinal alcohol or liquid extract must be mixed thoroughly with the amount of syrup in the prescription before adding other medicinal ingredients and carriers. If the amount of alcohol

For drugs under 2g, drop by drop can be taken using a standard dropper. If the amount of alcohol is less than 2g, a scale must be used.

- Soft and thick extracts are usually dissolved in hot syrup or glycerin.

- Drugs that are soluble in solvents and carriers are usually dissolved first and then filtered into bottles.

- For potions containing medicinal herbs, water must be boiled to decoct or steep the medicinal herbs. If there are no special instructions, the ratio of medicinal herbs, usually used to make decoction or steeping water, is 2% (medicinal herbs are leaves and flowers) and 4% (medicinal herbs are wood, stem, root).

- If the potio contains essential oils, grind the essential oils with a little sugar to disperse the essential oils, then mix with the amount of syrup in the recipe.

When preparing potio, care must be taken to avoid possible incompatibilities, especially chemical incompatibilities.

Because they contain a small amount of sugar, potios are a favorable environment for the growth of bacteria and mold. They should only be prepared when used or used within 1-2 days, and bottled in 60-125ml bottles. Potios should be stored in tightly closed bottles in a cool place.

4.5.3. Some examples

4.5.3.1. Cinnamon alcohol potion

Recipe: Cinnamon alcohol 4ml

Ethanol 20ml

Single syrup 20ml

Distilled water to 100ml

Dissolve cinnamon alcohol with ethanol. Add syrup, stir well. Add enough water to 100ml, mix well.

Orange solution, cinnamon smell, sweet and spicy taste. Store in a tightly closed bottle.

4.5.3.2. Gum potion

Recipe: 10g gum arabic powder

Single syrup 10ml

Distilled water 150ml

Grind gum with syrup, add orange blossom water, then add distilled water to make 150ml. The liquid is clear or slightly cloudy, light yellow, sweet with orange blossom smell.

Gum potio can be prepared according to the following formula: 25% gum arabic mucilage 20g

Orange syrup 20g

Distilled water to 100ml

Potassium gum is often used as a carrier for potassium containing solid pharmaceutical substances that are insoluble in water.

4.6. Elixir

4.6.1. Definition - preparation technique

Elixirs are liquid pharmaceutical preparations containing one or more active ingredients, usually containing a large proportion of ethanol and sucrose or polyalcohols (such as glycerin) along with some suitable additives (such as anti-mold preservatives...).

Elixir is usually prepared so that the dose is calculated in teaspoons (5ml). Elixir can be prepared in the form of powder packets, dry granules, and before use, the granules or powder are dissolved in water. The basic technique for preparing elixir is the same as preparing liquid medicine solutions and syrups. Because the ingredients contain ethanol, glycerin, and propylene glycol, elixir is more stable and has better SKD, and can be preserved longer.

4.6.2. Some examples

4.6.2.1. Paracetamol Elixir

Formula: Paracetamol 24g

Ethanol 96 0 100ml Propylene glycol 100ml

20ml chloroform alcohol

Single syrup 275ml

Colorants, flavorings, etc.

Glycerin 1000ml

Dissolve paracetamol in a mixture of ethanol, propylene glycol, chloroform alcohol, add colorant, flavoring agent, simple syrup, then add enough glycerin, stir well.

4.6.2.2. Phenobarbital Elixir

Formula: Phenobarbital

Ethanol 90 0 Glycerin

Colorants, flavorings

etc.

400g

Pure water etc.

1000ml

Maybe you are interested!

Dissolve phenobarbital in ethanol. Add remaining ingredients and then add enough water, stir well.

4.7. Medicinal alcohol (ethanol) solution

4.7.1 Definition - modulation technique

Alcohol solutions are liquid preparations for internal or external use, consisting of one or more medicinal substances completely dissolved in ethanol.

The solvents for preparing alcohol solutions are ethanol and ethanol-water mixtures, which can dissolve resins, essential oils, base alkaloids, and some other organic substances (resorcin, camphor, menthol, salicylic acid, etc.)

The solubility of chemicals in ethanol depends on the concentration of ethanol.

Solutions are usually prepared by completely dissolving the drug in the solvent. Ethanol solutions have their own sensory and physical-chemical properties, characteristic of the components in the solution.

To test alcohol solutions, we often conduct qualitative and quantitative identification of active ingredients, determine ethanol content and measure the density of the solution.

4.7.2. Some examples

4.7.2.1. 5% iodine alcohol

Formula: Iodine 5 g

Potassium iodide 2 g

Ethanol 70 0 vnd. 100 ml

Dissolve 2g potassium iodide in 10ml 700c ethanol , add crushed iodine then add 700c ethanol to make 100ml, stir until completely dissolved.

Clear, red-brown solution, characteristic odor. The preparation must contain at least 70% ethanol.

In this formula potassium iodide is both a dissolving intermediate and a stabilizing agent. I 2 + H 2 O  HI + HOI

HI + CH 3 - CH 2 OH  CH 3 - CH 2 I + H 2 O

HOI + CH 3 - CH 2 OH  CH 3 - CHO + H 2 O + HI CH 3 - CHO + HOI  CH 3 - COOH + HI

CH 3 - CH 2 OH + CH 3 - COOH  CH 3 - CH 2 - OOC - CH 3 + H 2 O

These reactions result in a change in color, an increase in acidity, and a decrease in iodine concentration of the preparation. If there is a trace of methanol in the ethanol, the methyliodide formed will irritate the skin and mucous membranes. If there is a trace of acetone in the ethanol, the acetone will be halogenated to form triiodoacetone CH 3 – CO – CI 3 . This substance is irritating to mucous membranes.

When potassium iodide is present, the following reactions will occur: I 2 + H 2 O  HI + HOI

HI + HOI + KI  KI 3 + H 2 O.

Therefore, the concentration of free iodine is not altered and the preparation has no irritating properties.

response

Store iodine tincture in a glass-stoppered bottle in a cool place.

4.7.2.2. Camphor Alcohol 10%

Formula: Natural or synthetic camphor 20g Ethanol 90 0 vnd. 200ml

Dissolve camphor in 80ml ethanol. Add enough ethanol to make 100ml.

4.7.2.3. Peppermint alcohol

Recipe: Peppermint essential oil 20g

Ethanol 90 0 vnd. 1000ml

Put peppermint essential oil and 90 0 ethanol in a bottle with a tight stopper. Close the bottle and shake to dissolve.

Clear, colorless solution with mint flavor.

4.8. High molecular weight solutions and colloidal solutions

4.8.1. High molecular solution:

Polymeric solutions are solutions containing solutes that are polymeric compounds, with molecular weights of tens of thousands to millions, and molecular lengths that can be 10 times the size of micelles in colloidal solutions. Polymeric compounds can have linear structures or complex anisotropic structures. When dissolved in solvents, polymers also form dispersions and are homogeneous systems. However, polymeric substances cannot pass through semipermeable membranes. At certain concentrations and temperatures, polymeric solutions can change from sol (a solution of molecules freely dispersed in a liquid solvent) to gel (interwoven molecules form a shaped network that traps solvent liquids in a network structure), the gel is a shaped substance that does not flow.

Due to the process of dissolving macromolecules through 3 stages: macromolecules swell due to solvation, continue to swell due to one-way diffusion of solvent into macromolecules, and finally

dissolution stage. Therefore, the technique of preparing high molecular solutions requires time to soak in solvent for swelling, then dissolve.

For example:

Pharmaceutical gelatin solution

Ingredients: Pharmaceutical gelatin 10g

Distilled water 180ml

Preparation: Soak gelatin in water until completely swollen (about 30 minutes), then heat in a water bath below 60 0 C, stir until completely dissolved, obtaining a homogeneous solution.

Indications: Use one tablespoon in case of gastric bleeding.

4.8.2. Colloidal solution

Colloidal solution is a heterogeneous microscopic system in which molecules aggregate into micelles (colloidal particles), ranging in size from nanometers to 0.1 micrometers. Colloidal solutions are very unstable and require colloidal protectors. Colloidal protectors are commonly used as high molecular weight substances, which in the solution play a role in increasing viscosity, creating a protective layer for colloidal particles, and preventing coagulation due to the aggregation of micelles.

Example: Protargol solution

Ingredients: Protargol 1g

Distilled water 200ml

Protargol is an odorless yellow-brown or brown powder with a slightly bitter taste. Protargon is a complex preparation of silver oxide and protein, in which the protein acts as a protective agent for colloidal silver oxide. Protargon contains 8% silver, usually mixed in a 1% solution for eye drops. A 0.5% solution is used for bladder irrigation.

Preparation: Pour about 150 ml of distilled water into a large cup. Gently sprinkle a thin layer of protargon on the surface of the water and let it stand until the protargon absorbs water, swells and dissolves completely into the solution. Do not stir when the protargon has not completely dissolved, because it will cause the protargon to stick together into lumps, and there will be air bubbles in the lumps, hindering the dissolution process. After the protargon has completely dissolved, stir well, filter the solution through cotton into a bottle, wash the cotton with distilled water and add up to the required volume.

Protargol solution is very sensitive to light. Under the effect of light, the silver oxide in protargon will decompose, turning into metallic silver. Store the solution in a colored glass bottle.

VALUATION

I. Choose true or false:

1. Protargol solution is very sensitive to light. Answer:

2. Colloidal solution is a heterogeneous microsystem. Answer:

3. Very soft water contains 0.5 - 1.5 mg equivalent of Ca 2+ and Mg 2+ ions in 1 liter. Answer: 4. The drug in anhydrous form is more soluble than in hydrated form. Answer: 5. Acidified water is a good solvent for dissolving organic compounds containing acids. Answer:

6. It is possible to convert lemon juice into effervescent preparations. Answer:

7. Surfactants can alter the pharmacological effects of drugs. Answer:

8. Lemon juice contains CO2 and should not be filtered after mixing. Answer:

9. When storing medicinal syrup, sugar can crystallize, making the syrup thinner and more susceptible to spoilage.

10. Weak base drugs will dissolve better when the pH of the aqueous solution increases. Answer:

II. Choose the best answer:

1. When classifying dosage forms according to dispersion systems, drug solutions are classified as dispersions:

a. Heterogeneous b. Superheterogeneous

c. Homogeneous d. Heterogeneous and microheterogeneous

2. The main advantages in terms of bioavailability of oral solutions are:

a. Drug absorption does not depend on food.

b. Short drug retention time.

c. Drugs that undergo little first-pass metabolism in the liver

d. The drug is absorbed quickly.

3. The solvent that is most miscible with water and has the greatest polarity among the following four solvents is:

a. Ethanol b. Glycerin

c. Propylenglycol d. Polyethylene glycol 400

4. The solubility of the drug in the solvent is:

a. The ratio between the solute and the amount of solvent in the solution at equilibrium.

b. Ratio between solute and solvent in solution

c. The ratio between the solute and the amount of solvent in a saturated solution at a given temperature.

d. The ratio between the solute and the amount of solvent in a supersaturated solution at a given temperature.

5. Alcohol not used to mix oral medication solutions is:

a. Ethanol b. Methanol

c. Isopropane d. Propylene glycol

6. Demineralized water cannot be used as a substitute for distilled water in any preparation:

a. Injection medication. b. Oral medication

c. Topical solution. D. Drug solution prepared by extraction method.

7. The basic difference between Elixir and Potio is:

a. Has high stability. b. Has a high alcohol content.

c. Can be mass-produced d. Has good bioavailability

8. When mixing 5% iodine alcohol solution, KI must be added to:

a. Increases the solubility of iodine b. Makes the solution stable

c. Reduces the sublimation of iodine d. Increases the effect of iodine

9. To prepare perfume with high essential oil content, you must:

a. Distill medicinal herbs containing essential oils with water

b. Use Talc powder to disperse essential oils into water.

c. Use surfactants such as TW 20 to dissolve essential oils.

d. Use essential oil alcohol solution.

10. The solvent to prepare Bromoform solution is:

a. Glycerin

b. Ethanol – water mixture

c. Glycerin – Ethanol mixture

d. Glycerin-gum mixture

III. Fill in the blanks:

1. Write the two main components of the drug solution: a. ............ b. ...............

2. Vegetable oil is a solvent that dissolves fat-soluble vitamins such as: a. ............... b. ........................

c. Vitamin E

3. There are 5 factors that affect the solubility of drugs in liquids:

a. The nature of the solute and solvent. b. .....................................

c. ....................................

c. Polymorphism and Solvation d. .....................................

4. Filtration is the process of removing .....(A)........ insoluble in solution by passing the solution through suitable....(B)........

5. Alcohol solutions are liquid preparations used in or....(A)....... consisting of one or more medicinal substances completely dissolved in......(B).......

6. To quickly dissolve the drug in oil, you can use ....(A)....which can be mixed with oil to

..(B).......

7. When dissolving high molecular solutions, it is necessary to let the solute...(a)...., ....(B)..., then it can easily dissolve in water.

8. For drugs that are difficult to dissolve in oil, it is possible to use........ to dissolve.

9. If the potion contains medicinal alcohol or liquid extract, it must contain ...(A).... medicinal alcohol or liquid extract with ...(B).... contained in the prescription before ...(C).... other and carrier substances.

10. In the formula for preparing 5% iodine alcohol, potassium iodide is both ...(A)..., and ....(B).....

IV. Answer the following questions:

1. Select the correct mixing sequence for the following solutions:

a. Phenolbarbital 0.3g

Ethanol 90 0 40g

Glycerin 40g

Distilled water to 100ml

b. Digitalin Ten centigrams Ethanol 90 0 46g

Glycerin 40g

Distilled water to 100ml

2. Compare syrup and Potio medicine?

3. Describe the filtration methods used in preparing pharmaceutical solutions?