Solutions

A solution is a liquid preparation containing one or more soluble chemicals dissolved in a suitable solvent or a mixture of mutually soluble solvents. A preparation prepared by dissolving a solid, liquid or gas in another liquid. Many pharmaceutical chemicals can only dissolve slowly in the solvent, which takes longer to fully dissolve. In order to improve the dissolution rate, several technologies can be adopted, such as heating, reducing the particle size of solute, using solubilizer or stirring. When solvent dissolution is promoted by heating, ensure that the material is thermally stable and non-volatile. Drug solutions include medicated water, aromatic perfume, enema, gargle, gargle, nasal wash, spray, ear solution, inhalant.

Fig.1 Pharmaceutical solutions.

The team of CD Formulation is leading experts in all aspects of pharmaceutical formulation development and dosage form optimization, we can accord the characteristics of the API and the development goals of the customers to design the formulation of solutions. CD Formulation can provide you with one-stop service to meet your needs of solutions.

Components of Pharmaceutical Solutions

• The vehicle, usually purified water.
• Co-solvents, e.g. propylene glycol, glycerin, alcohol
• Surface-active agents specifically to enhance solubility of the therapeutic agent in the vehicle.
• Preservatives, e.g. parahydroxybenzoate esters (methylhydroxybenzoate and propylhydroxybenzoate),
• Sweeteners, e.g. glucose, saccharin, aspartame
• Rheology (viscosity) modifiers, e.g. hydrophilic polymers (cellulose derivatives, alginic acid, polyvinylpyrrolidone)
• Antioxidants, e.g. sodium formaldehyde sulphoxylate, butylated hydroxyanisole, butylated hydroxytoluene
• Buffers to regulate the pH of the formulation, e.g. citrate buffer

Advantages of Solutions:

• The drug is immediately available for absorption. By providing the drug in the solution, absorption of the dissolved phase can be bypassed.
• Flexible dosing, the active components in the solutions exist at a certain concentration per unit volume.
• The solution is designed for any absorption route: the oral administration route through parenteral (injection), rectal enema, local (for skin) and ophthalmic preparations is solutions.
• There is no need to shake the container. Unlike suspension, the active components are dissolved in the carrier.
• Easy to swallow in difficult situations (such as babies or old people). Patients take the solution more easily.

The Process of Developing Solutions

When preparing solutions, the only equipment necessary is suitable mixing vessels, a means of agitation and a filtration system. Generally, three methods are applied in the preparation of solutions:

• Simple Solution: prepared by dissolving the solute in the solvent.
• Solution by chemical reaction: prepared by reacting two or more solutes with each other in a suitable solvent.
• Solution by extraction: vegetables or animal origin are often extracted with suitable solvent.

If you have a requirement about solutions services, please contact us by phone or email, our colleagues will reply to you within three working days.

References

1. White J, Belmont M, Metcalfe C. Pharmaceutical Compounds in Wastewater: Wetland Treatment as a Potential Solution[J]. The Scientific World Journal, 2011, 6(2): 1731-1736.
2. Spooner N, Zamora I, Marshall-Waggett C, et al. Clinical and Pharmaceutical Solutions through Analysis: Europe 2018[J]. Bioanalysis, 2018, 10(16): 1251-1253.
3. Barbagli A, Jensen B N, Raza M, et al. Assessment of Soil Buffer Capacity on Nutrients and Pharmaceuticals in Nature-based Solution Applications[J]. Environmental Science & Pollution Research, 2019, 26: 759-774.