物理药剂学PPT精选课件
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The methods to prepare lyophobic colloids
• Dispersion methods 1,grinding method 2,sonication dispersion method 3,arc discharge method
• Condensation methods 1,physical methods 2,chemical methods
Grains of sand,most pharmaceutical emulsions and suspension, red blood cells
2
Types of Colloidal dispersion
Lyophilic colloids Lyophobic colloids Association colloids
Less than 1 nm
Invisible in electron microscope Pass through ultrafilter and semipermeable membrane undergo rapid diffusion
Oxygen molecules, ordinary ions, glucose
• 1,dialysis method • 2,ultrafiltration
15
dialysis method
• Semipermeable membrane
16
dialysis method
• Electrodialysis
17
ultrafiltration
• Semipermeable membrane
4
5
6
Lyophobic colloids
Lyophobic colloids is composed of materials that have little attraction. e.g. gold, silver, sulfur, arsenous sulfide, and silver iodide.
+3HCl • 2H2S(w）+ SO2(g) → 2H2O +3S (sol） • Na2S2O3 +2HCl → 2NaCl +H2O +SO2 +S (sol) • 2HAuCl4+ 3HCHO +11KOH → 2Au(sol）
+3HCOOK + 8KCl + 8H2O
14
Sol purification
8
Baidu Nhomakorabea
grinding method
9
sonication dispersion method
10
arc discharge method
• Owing to the intense heat generated by the arc, some of the metal of the electrodes is dispersed as vapor, which condenses to form colloidal particles.
18
ultrafiltration
• Electro ultrafiltration
11
Physical condensation methods
1,replacement of solvent
12
Physical condensation methods
2, Steam quench method
13
chemical condensation methods
• 2H3AsO3（w）+ 3H2S →As2S3（sol）+6H2O • FeCl3 （w）+3H2O （H）→ Fe(OH)3 （sol）
Colloidal dispersion
From 1 nm to o.5 μm
Not resolved by ordinary microscope (although may be detected under ultramicroscope) Visible in electron microscope Pass though filter paper Do not pass semipermeable membrane Diffusion very slowly
3
Lyophilic colloids
Systems containing colloidal particles that interact to an appreiable extent with the dispersion medium are referred to as lyophilic(solventloving)colloids. hydrophilic sols: gelatin, acacia, insulin, albumin Lipophilic colloids: rubber, polystyrene. A material that forms a lyophilic colloidal system in one liquid(e.g. water) may not do so in another liquid(e.g. benzene).
Colloidal dispersion system
1
Classification of dispersed system based on particle
size
class
Particle size
Characteristics of system
example
Molecular dispersion
Colloidal silver sols, natural and synthetic polymers, cheese, butter, jelly, milk, etc.
Coarse dispersion
Greater than o.5 μm
Visible under microscope Do not passthough normal filter paper Do not dialyze though semipermeable menmbrane Do not diffusion
The methods to prepare lyophobic colloids
• Dispersion methods 1,grinding method 2,sonication dispersion method 3,arc discharge method
• Condensation methods 1,physical methods 2,chemical methods
Grains of sand,most pharmaceutical emulsions and suspension, red blood cells
2
Types of Colloidal dispersion
Lyophilic colloids Lyophobic colloids Association colloids
Less than 1 nm
Invisible in electron microscope Pass through ultrafilter and semipermeable membrane undergo rapid diffusion
Oxygen molecules, ordinary ions, glucose
• 1,dialysis method • 2,ultrafiltration
15
dialysis method
• Semipermeable membrane
16
dialysis method
• Electrodialysis
17
ultrafiltration
• Semipermeable membrane
4
5
6
Lyophobic colloids
Lyophobic colloids is composed of materials that have little attraction. e.g. gold, silver, sulfur, arsenous sulfide, and silver iodide.
+3HCl • 2H2S(w）+ SO2(g) → 2H2O +3S (sol） • Na2S2O3 +2HCl → 2NaCl +H2O +SO2 +S (sol) • 2HAuCl4+ 3HCHO +11KOH → 2Au(sol）
+3HCOOK + 8KCl + 8H2O
14
Sol purification
8
Baidu Nhomakorabea
grinding method
9
sonication dispersion method
10
arc discharge method
• Owing to the intense heat generated by the arc, some of the metal of the electrodes is dispersed as vapor, which condenses to form colloidal particles.
18
ultrafiltration
• Electro ultrafiltration
11
Physical condensation methods
1,replacement of solvent
12
Physical condensation methods
2, Steam quench method
13
chemical condensation methods
• 2H3AsO3（w）+ 3H2S →As2S3（sol）+6H2O • FeCl3 （w）+3H2O （H）→ Fe(OH)3 （sol）
Colloidal dispersion
From 1 nm to o.5 μm
Not resolved by ordinary microscope (although may be detected under ultramicroscope) Visible in electron microscope Pass though filter paper Do not pass semipermeable membrane Diffusion very slowly
3
Lyophilic colloids
Systems containing colloidal particles that interact to an appreiable extent with the dispersion medium are referred to as lyophilic(solventloving)colloids. hydrophilic sols: gelatin, acacia, insulin, albumin Lipophilic colloids: rubber, polystyrene. A material that forms a lyophilic colloidal system in one liquid(e.g. water) may not do so in another liquid(e.g. benzene).
Colloidal dispersion system
1
Classification of dispersed system based on particle
size
class
Particle size
Characteristics of system
example
Molecular dispersion
Colloidal silver sols, natural and synthetic polymers, cheese, butter, jelly, milk, etc.
Coarse dispersion
Greater than o.5 μm
Visible under microscope Do not passthough normal filter paper Do not dialyze though semipermeable menmbrane Do not diffusion