Diese Präsentation wurde erfolgreich gemeldet.
Wir verwenden Ihre LinkedIn Profilangaben und Informationen zu Ihren Aktivitäten, um Anzeigen zu personalisieren und Ihnen relevantere Inhalte anzuzeigen. Sie können Ihre Anzeigeneinstellungen jederzeit ändern.
BY,
DIVYA THAKUR,
MPHARMACY(I.P),
1600-4P-1304,
MICROSPHERES
HISTORY:
 The concept of packing microscopic quantities of material with in
microspheres dates to 1930’s the work of Bung...
 Microspheres are solid spherical particles ranging in size from
1-1000µm. They are spherical free flowing particles cons...
ADVANTAGES OF MICROSPHERES:
 1. Particle size reduction for enhancing solubility of the poorly soluble drug.
 2. provide...
DISADVANTAGES:-
1. The costs of the materials and processing of the controlled release
preparation, are substantially high...
Ideal characteristics of microspheres:
 The ability to incorporate reasonably high concentrations of the
drug.
 Stabilit...
TYPES OF MICROSPHERE
MUCO
ADHESIVE
MICROSPHERES
FLOATING
MICROSPHERS
RADIO ACTIVE
MICROSPHERES
BIO ADHESIVE
MICROSPHERES
M...
BIOADHESIVE MICROSPHERES:-
 Adhesion of drug delivery device to the mucosal membrane such as buccal,
ocular, rectal , nas...
MAGNETIC MICROSPHERES:
 This kind of delivery system is very much important which localises the drug to the
disease site....
FLOATING MICROSPHERES:
 In floating types the bulk density is less than the gastric fluid and so remains
buoyant in stoma...
4 RADIOACTIVE MICROSPHERES:-
 Radio embolization therapy microspheres sized 10-30nm are of larger
than the diameter of th...
POLYMERIC MICROSPHERE:-
The various types of polymers are used for preparation of microspheres
e.g:- Albumin microspheres
...
MATERIALS USED:-
Microspheres used usually are polymers.
They are classified into two types:
 Synthetic Polymers
 Natura...
PREPERATION METHODS:-
1)SOLVENT EVOPERATION METHOD
2)SINGLE EMULSION TECHNIQUE
3)DOUBLE EMULSION TECHNIQUE
4)POLYMERISATIO...
SPRAY DRYING:-
polymer is first dissolved in a suitable volatile organic
solvent
The drug in the solid form is then disper...
 The microcapsule coating is dispersed in a volatile solvent which is
immiscible with the liquid manufacturing vehicle ph...
SINGLE EMULSION TECHNIQUE
DOUBLE EMULSION TECHNIQUE
NORMAL POLYMERIZATION:-
BULK POLYMERIZATION:-
MONOMER OR
COMBINATION
OF MONOMERS
INITIATOR OR
CATALYST
HEATED POLYMER
MOUL...
SUSPENSION POLYMERIZATION:-
 Suspension polymerization also referred as bead or pearl polymerization.
 It is carried out...
INTERFACIAL POLYMERIZATION:-
 Interfacial polymerization essentially precedes involving reaction of
various monomers at t...
COACERVATION PHASE SEPERATION TECHNIQUE
AQ/ORGANIC POLYMER
DRUG DISSOLVED/DISPERSED IN
POLYMER SOLUTION
POLYMER RICH GLOBU...
7. Solvent extraction:
 Solvent evaporation method is used for manufacturing of microparticles ,
involves removal of the ...
DRUG RELEASE KINETICS
FOR RESERVOIR TYPE SYSTEM:-
The release is essentially governed by ficks first law of diffusion as
J...
MATRIX TYPE SYSTEMS:-
If drug is dissolved in polymer matrix
For 60%of drug released
For remaining amount of drug
I =thick...
If the drug is dispersed through out the polymer matrix
It is given by higuchi’s equation
A= area of matrix
Cs = solubilit...
EVALUATION OF MICROSPHERES:
1. Particle size and shape:
The most widely used procedures to visualize microparticles are
co...
5. Angle of contact:
The angle of contact is measured to determine the wetting property of a micro
particulate carrier.
6....
1. Ophthalmic Drug Delivery
2. Oral drug delivery
3. Gene delivery
4. Nasal drug delivery
5. Intratumoral and local drug d...
CONCLUSION:-
Microspheres are having wide applications in drug delivery systems. Most
important are the targeted drug deli...
REFERENCE:-
VYAS AND KHAR PAGE NO 417-436
REVIEW ARTICLE BY KADAM N.R AND SUVARNA V
ARTICLE FROM IOSR JOURNAL OF PHARMA...
Microspheres
Nächste SlideShare
Wird geladen in …5
×

Microspheres

10.016 Aufrufe

Veröffentlicht am

microspheres ,types, preperation methods, advantages , disadvantages

Veröffentlicht in: Bildung

Microspheres

  1. 1. BY, DIVYA THAKUR, MPHARMACY(I.P), 1600-4P-1304, MICROSPHERES
  2. 2. HISTORY:  The concept of packing microscopic quantities of material with in microspheres dates to 1930’s the work of Bungenberg de jong and co- workers on the entrapment of substance with coacervates.
  3. 3.  Microspheres are solid spherical particles ranging in size from 1-1000µm. They are spherical free flowing particles consisting of proteins or synthetic polymers.  The microspheres are free flowing powders consisting of proteins or synthetic polymers, which are biodegradable in nature. There are two types of microspheres 1) Microcapsules. 2)Micromatrices. INTRODUCTION:
  4. 4. ADVANTAGES OF MICROSPHERES:  1. Particle size reduction for enhancing solubility of the poorly soluble drug.  2. provide constant and prolonged therapeutic effect.  3. provide constant drug concentration in blood there by increasing patent compliance.  4. Decrease dose and toxicity.  5. Protect the drug from enzymatic and photolytic cleavage hence found to be best for drug delivery  6. Reduce the dosing frequency and thereby improve the patient compliance  7. Better drug utilization will improve the bioavailability and reduce the incidence or intensity of adverse effects.  8. Protects the GIT from irritant effects of the drug.  9. Biodegradable microspheres have the advantage over large polymer implants in that they do not require surgical procedures for implantation and removal.  10. Controlled release delivery biodegradable microspheres are used to control drug release rates there by decreasing toxic side effects, and eliminating the inconvenience of repeated injections. .
  5. 5. DISADVANTAGES:- 1. The costs of the materials and processing of the controlled release preparation, are substantially higher than those of standard formulations. 2. The fate of polymer matrix and its effect on the environment. 3. The fate of polymer additives such as plasticizers , stabilizers, antioxidants and fillers. 4. Reproducibility is less. 5. Process conditions like change in temperature, pH, solvent addition, and evaporation/agitation may influence the stability of core particles to be encapsulated. 6. The environmental impact of the degradation products of the polymer matrix produced in response to heat, hydrolysis, oxidation, solar radiation or biological agents.
  6. 6. Ideal characteristics of microspheres:  The ability to incorporate reasonably high concentrations of the drug.  Stability of the preparation after synthesis with a clinically acceptable shelf life.  Controlled particle size and dispersability in aqueous vehicles for injection.  Release of active reagent with a good control over a wide time scale.  Biocompatibility with a controllable biodegradability.  Susceptibility to chemical modification.
  7. 7. TYPES OF MICROSPHERE MUCO ADHESIVE MICROSPHERES FLOATING MICROSPHERS RADIO ACTIVE MICROSPHERES BIO ADHESIVE MICROSPHERES MAGNETIC MICROSPHERES POLYMERIC MICROSPHERES
  8. 8. BIOADHESIVE MICROSPHERES:-  Adhesion of drug delivery device to the mucosal membrane such as buccal, ocular, rectal , nasal etc. can be termed as bio adhesion.  These kinds of microspheres exhibit a prolonged residence time at the site of application and causes intimate contact with the absorption site and produces better therapeutic action
  9. 9. MAGNETIC MICROSPHERES:  This kind of delivery system is very much important which localises the drug to the disease site.  In this larger amount of freely circulating drug can be replaced by smaller amount of magnetically targeted drug.  Magnetic carriers receive magnetic responses to a magnetic field from incorporated materials that are used for magnetic microspheres are chitosan , dextran etc. The different types of a.Therapeutic magnetic microspheres:- used to deliver chemotherapeutic agent to liver tumour. Drugs like proteins and peptides can also be targeted through this system. b. Diagnostic microspheres:- used for imaging liver metastases and also can be used to distinguish bowel loops from other abdominal structures by forming nano size particles supra magnetic iron oxides
  10. 10. FLOATING MICROSPHERES:  In floating types the bulk density is less than the gastric fluid and so remains buoyant in stomach without affecting gastric emptying rate.  The drug is released slowly at the desired rate, and the system is found to be floating on gastric content and increases gastric residence and increases fluctuation in plasma concentration.  Moreover it also reduces chances of dose dumping.  It produces prolonged therapeutic effect and therefore reduces dosing frequencies.  Drug (ketoprofen)is given in the form of floating microspheres
  11. 11. 4 RADIOACTIVE MICROSPHERES:-  Radio embolization therapy microspheres sized 10-30nm are of larger than the diameter of the capillaries and gets tapped in first capillary bed when they come across.  They are injected in the arteries that leads them to tumour of interest so all these conditions radioactive microspheres deliver high radiation dose to the targeted areas without damaging the normal surrounding tissues.  It differs from drug delivery system, as radio activity is not released from microspheres but acts from within a radioisotope typical distance and  The different kinds of radioactive microspheres are α emitters, β emitters, γ emitters.
  12. 12. POLYMERIC MICROSPHERE:- The various types of polymers are used for preparation of microspheres e.g:- Albumin microspheres  Gelatin microspheres  Starch microspheres  Dextran microspheres  Carrageenan microspheres  Alginate microspheres  Poly (alkyl cyanoacrylate ) microspheres etc.,
  13. 13. MATERIALS USED:- Microspheres used usually are polymers. They are classified into two types:  Synthetic Polymers  Natural polymers Synthetic polymers are divided into two types.  a) Non-biodegradable polymers:- Poly methyl methacrylate (PMMA), Acrolein, Glycidyl methacrylate, Epoxy polymers  b) Biodegradable polymers:-Lactides, Glycolides & their co polymers, Poly alkyl cyanoacrylates, Poly anhydrides Natural polymers obtained from different sources like proteins, carbohydrates and chemically modified carbohydrates  Proteins: Albumin, Gelatin, Collagen  Carbohydrates: Agarose, Carrageenan, Chitosan, Starch  Chemically modified carbohydrates: Poly dextran, Poly starch
  14. 14. PREPERATION METHODS:- 1)SOLVENT EVOPERATION METHOD 2)SINGLE EMULSION TECHNIQUE 3)DOUBLE EMULSION TECHNIQUE 4)POLYMERISATION TECHNIQUE  NORMAL POLYMERISATION  BULK POLYMERISATION  SUSPENSION POLYMERISATION  EMULSION POLYMERISATION  INTERFACIAL POLYMERISATION 5)COACERVATION PHASE SEPERATION TECHNIQUE 6)SPRAY DRYING 7)SOLVENT EXTRACTION
  15. 15. SPRAY DRYING:- polymer is first dissolved in a suitable volatile organic solvent The drug in the solid form is then dispersed in the polymer solution with high speed homogenization Atomization in hot air Microspheres
  16. 16.  The microcapsule coating is dispersed in a volatile solvent which is immiscible with the liquid manufacturing vehicle phase.  A core material to be microencapsulated is dissolved or dispersed in the coating polymer solution. With agitation the core material mixture is dispersed in the liquid manufacturing vehicle phase to obtain the appropriate size microcapsule.  The mixture is then heated if necessary to evaporate the solvent for the polymer of the core material is disperse in the polymer solution, polymer shrinks around the core.  If the core material is dissolved in the coating polymer solution, matrix – type microcapsules are formed.  The core materials may be either water soluble or water in soluble materials.  Solvent evaporation involves the formation of an emulsion between polymer solution and an immiscible continuous phase whether aqueous (o/w) or non-aqueous. SOLVENT EVAPORATION:
  17. 17. SINGLE EMULSION TECHNIQUE
  18. 18. DOUBLE EMULSION TECHNIQUE
  19. 19. NORMAL POLYMERIZATION:- BULK POLYMERIZATION:- MONOMER OR COMBINATION OF MONOMERS INITIATOR OR CATALYST HEATED POLYMER MOULDED MICROSPHERES Drug loading may be done during the polymerization process
  20. 20. SUSPENSION POLYMERIZATION:-  Suspension polymerization also referred as bead or pearl polymerization.  It is carried out by heating the monomer or composition of monomers as droplets dispersion in a continuous aqueous phase.  Droplets may also contain an initiator and other additives EMULSION POLYMERIZATION:-
  21. 21. INTERFACIAL POLYMERIZATION:-  Interfacial polymerization essentially precedes involving reaction of various monomers at the interface between the two immiscible liquid phases to form a film of polymer that essentially envelops the dispersed phase.  The monomers present in either phases diffuse rapidly and polymerize rapidly at the interface.  Monomer droplet,the formed carrier is of capsular (reservoir)type.
  22. 22. COACERVATION PHASE SEPERATION TECHNIQUE AQ/ORGANIC POLYMER DRUG DISSOLVED/DISPERSED IN POLYMER SOLUTION POLYMER RICH GLOBULES MICROSPHERES IN AQ/ORGANIC PHASE MICROSPHERES DRUG PHASE SEPERATION INDUCED BY DIFFERENT MEANS HARDENING SEPERATION,DRYING
  23. 23. 7. Solvent extraction:  Solvent evaporation method is used for manufacturing of microparticles , involves removal of the organic phase by extraction of the or non aqueous solvent.  This method involves water miscible organic solvents like isopropanol .  Organic phase can be removed by extraction with water.  This process decreases the hardeningtime for the microspheres.  One variation of the process involves direct incorporation of the drug or protein to polymer organic solution.  Rate of solvent removal by extraction method depends on the temperature of water, ratio of emulsion volume to the water and solubility profile of polymer.
  24. 24. DRUG RELEASE KINETICS FOR RESERVOIR TYPE SYSTEM:- The release is essentially governed by ficks first law of diffusion as J = flux per unit area D = diffusion coefficient Dc/dx = concentration gradient Diffusion across the membrane determines the effectiveness of the carrier systems Cummilative a amount of drug released through unit area ‘Q’ at time ‘t’ is given by equation CS = saturation solubility of drug in dispersion medium. Dm = diffusion coefficient of drug in membrane of thickness Im. Dd = diffusion coefficient of drug in static diffussion layer of thickness Id. k = partition coefficient of drug between membrane and reservoir compartment . J = -D(dc/dt) Q = CS k DmDd t KDMIM +Dd Id
  25. 25. MATRIX TYPE SYSTEMS:- If drug is dissolved in polymer matrix For 60%of drug released For remaining amount of drug I =thickness of polymer slab D=diffusion coefficient Mx =total amount of drug present in the matrix Mt = total amount of drug released in time t
  26. 26. If the drug is dispersed through out the polymer matrix It is given by higuchi’s equation A= area of matrix Cs = solubility of the drug in matrix Co = total concentration in matrix
  27. 27. EVALUATION OF MICROSPHERES: 1. Particle size and shape: The most widely used procedures to visualize microparticles are conventional light microscopy (LM) and scanning electron microscopy (SEM). 2. Electron spectroscopy for chemical analysis: The surface chemistry of the microspheres can be determined using the electron spectroscopy for chemical analysis (ESCA). 3. Density determination: The density of the microspheres can be measured by using a multi volume pycnometer. 4. Isoelectric point: The micro electrophoresis is used to measure the electrophoretic mobility of microspheres from which the isoelectric point can be determined.
  28. 28. 5. Angle of contact: The angle of contact is measured to determine the wetting property of a micro particulate carrier. 6. In vitro methods: Release studies for different type of microspheres are carried out by using different suitable dissolution media, mostly by rotating paddle apparatus (USP /BP). 7. Drug entrapment efficiency: Drug entrapment efficiency can be calculated using following equation, % Entrapment = Actual content/Theoretical content x 100. 8. Swelling index : The swelling index of the microsphere was calculated by using the formula, Swelling index= (mass of swollen microspheres – mass of dry microspheres) 100 (mass of dried microspheres)
  29. 29. 1. Ophthalmic Drug Delivery 2. Oral drug delivery 3. Gene delivery 4. Nasal drug delivery 5. Intratumoral and local drug delivery 6. Buccal drug delivery 7. Gastrointestinal drug delivery 8. Transdermal drug delivery 9. Colonic drug delivery 10. Vaginal drug delivery 11. Targeting by using microparticulate carriers APPLICATION OF MICROSPHERES IN PHARMACEUTICAL INDUSTRY:
  30. 30. CONCLUSION:- Microspheres are having wide applications in drug delivery systems. Most important are the targeted drug delivery ,Controlled and sustained drug delivery .By combining various strategies, microspheres will find central place in novel drug delivery mainly particularly in cell sorting, diagnostics and Genetic engineering.
  31. 31. REFERENCE:- VYAS AND KHAR PAGE NO 417-436 REVIEW ARTICLE BY KADAM N.R AND SUVARNA V ARTICLE FROM IOSR JOURNAL OF PHARMACY (IOSRPHR) BY RAMTEKE K.H, JADHAV V.B, DHOLE S.N. ARTICLE FROM INTERNATIONAL JOURNAL OF PHARMACEUTICAL AND CHEMICAL SCIENCES BY VIKRANT K. NIKAM, VR. GUDSOORKAR, SN. HIREMATH, R.T. DOLAS AND VA. KASHID IMAGE SOURCE:- WWW.GOOGLE.COM

×