LIQUID DOSAGE FORMS (part 3) SOLUTIONS OF HIGH-MOLECULAR COMPOUNDS. COLLOIDAL SOLUTIONS

High-molecular compounds are the natural or synthetic substances with a big molecular weight from several thousands to not less than thousands, sometimes one million and more.

CHARACTERISTIC OF HМС Natural HМС starch,dextrin,cellulose,polyglucine,pectin,alginas,agaroid,collagen,pepsin,tripsin,chemotripsin,pancreatin,gelatin,gelatinosa Synthetic and semi- synthetic HMC methylcellulose; sodium carboximethyl- cellulose; sodium carboximethyl- cellulose; polyvinol; polyvinol; polyvinilpirrolidone; polyvinilpirrolidone;polyacrilamide;polyaethylenoxide;silicons; non-ionic surface active substances: spenes; twins.

Unlimited swelling: the process of transition from swelling to dissolution takes place spontaneously

Limited swelling: the process of transition from swelling to dissolution takes place under different factors (the increase of temperature, etc.)

PROPERTIES OF HМС SOLUTIONS The same with the true solutions: Medicinal substances are refined until the molecule condition. During dissolving of HMC their solutions are formed spontaneously. HMC solutions are homogeneous systems (there is no interface between the dissolved substance and the solvent). HMC are thermodynamic balanced systems. HMC solutions: have the Brownian movement; have the Brownian movement; do not have the Tyndal effect. do not have the Tyndal effect.

The properties, which are different from true solutions The large size of molecules. The low osmotic pressure. The low osmotic pressure. The poor ability to diffusion. The poor ability to diffusion. HMC solutions haven't ability to dialysis. HMC solutions haven't ability to dialysis. HMC solution can be changed by the influence of the external factors (e.g., due to adding of electrolytes, the change of temperature). HMC solution can be changed by the influence of the external factors (e.g., due to adding of electrolytes, the change of temperature).

PROCESSES OCCURRING IN HMC SOLUTIONS DUE TO THE INFLUENCE OF THE EXTERNAL FACTORS AND FACTORS, WHICH CAN BE A CAUSE OF DESTRUCTION IN COLLOIDAL SOLUTIONS

The coagulation - is a process of integration of the disperse phase particles due to sticking them together.

Salting out - is a process of the HМС isolation from the solution as a flocky precipitate.

Coacervation - is a process of the system’s delamination into two layers.

Gelatinization - is a special intermediate form of a system being – jelly or gel – which is characterized by loosing of fluidity.

Syneresis - is a phenomenon of gelatinization happening inside the jelly, which can reduce to a system separation into 2 phases: the concentrated jelly and the solvent containing HМС molecules.

Rp.: Pepsini 2.0 Acidi hydrochlorici 5 ml Aquae purificatae 200 ml Misce. Da. Signa. Use 1 table-spoon 3 times a day during meals.

V = 205 ml; V = 205 ml; Number of applications: 205 ml/15 ml  14. Hydrochloric acid 8.3 %: H.S.D. = 5 ml/14 = 0.36 mH.D.D. = 0.36  3 = 1.08 ml WCP (reverse side) WCP (reverse side) Pepsin 2.0 Solution hydrochloric acid 0.83 % (1:10) 5  10 = 50 ml Purified water : = 155 ml

WCP (front side) WCP (front side) Date № Pr. Aquae purificatae 155 ml Sol. Acidi hydrochlorici diluti (1:10) 50 ml Pepsini 2.0 Vtotal = 205 ml Vtotal = 205 ml Prepared by(signature) Checked by (signature)

Rp.: Solutionis Gelatinae 5 % 50.0 Da. Signa. Use 1 table-spoon every 2 hours. WCP (reverse side) WCP (reverse side) Gelatin 2.5 Purified water: 50.0 – 2.5 = 47.5 (47.5 ml)

WCP (front side) WCP (front side) Date№ Pr. Gelatinae 2.5 Aquae purificatae 47.5 ml mtotal = 50.0 mtotal = 50.0 Prepared by:(signature) Checked by: (signature)

Colloidal solutions are ultramicroheterogeneous systems, where the structural unit is a complex of molecules, atoms and ions called micelle.

PROPERTIES OF COLLOIDAL SOLUTIONS 1. A poor ability to diffusion. 2. The low osmotic pressure. 3. A poor ability to dialysis. 4. The ability to disperse light in all sides when examining solutions in the ambient light (the characteristic cone of Тyndal will be obtained). 5. Micelles in the colloidal solution are in random movement. They are characterized by the Brownian movement. 6. Colloidal solutions are stable sedimentation systems. 7. Colloidal solutions are aggregative and thermodynamic unstable systems.

The protected colloidal medicines Collargol (a strong-effective substance) Collargolum (Argentum colloidale)Silver oxide 70 % Protargol Protargolum (Argentum proteinicum) Silver oxide 8 % Ichthyol Ichthyolum