Resealed Erythrocytes:Introduction, Isolation of erythrocytes, Methods of drug loading, Applications of resealed erythrocytes, Advantages of erythrocytes as carriers, Disadvantages of erythrocytes as carriers,Recent developments and Future perspective.

1. RESEALED ERYTHROCYTES
A seminar to submitted to the
Jawaharlal Nehru Technological University, Hyderabad
In partial fulfillment of the requirements for the degree of
BACHELOR OF PHARMACY
By
RUQSAR FATIMA 15S61R0016
Under the guidance of
Ms. Sameena Begum, M. Pharm.,
Assistant Professor
Department of Pharmaceutics
Anwarul Uloom College of Pharmacy
New Mallepally, Hyderabad -500001
Affiliated to JNTUH , Approved by AICTE and PCI
September-2018
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2. 2

3. CONTENTS
Introduction.
Isolation of erythrocytes.
Methods of drug loading.
Applications of resealed erythrocytes.
 Advantages of erythrocytes as carriers.
Disadvantages of erythrocytes as carriers.
Recent developments and Future perspective.
Conclusion.
References.
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4. INTRODUCTION
Drug loading in body´s own erythrocytes when used to
serve as controlled delivery system.
 They can be loaded with a variety of chemically and
biologically active compounds using various chemical and
physical methods.
They have potential carrier capabilities for the delivery of
drugs.
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5. ISOLATION OF RESEALED
ERYTHROCYTES:
Erythrocytes may be prepared as carriers from humans
beings,rat,mice,etc.
To isolate erythrocytes,blood is collected in heparinised
tubes by venipuncture.
Fresh whole blood is collected and immediately chilled to
40ºC and stored for less than 2 days.
Erythrocytes are harvested and washed by centrifugation.
The washed cells are suspended in buffer solutions and
often stored in acid-citrate-dextrose buffer at 4º C upto 48
hrs before use. 5

6. METHODS OF DRUG LOADING
Membrane
perturbation
Endocytosis
method
Hypo-osmotic
lysis
Preswell
method
Dialysis
method
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7. MEMBRANE PERTURBATION METHOD
RBC
Amphotericin B
ex:chemical
agents
Increased
permeability
Drug
Resealing buffer
Resealed
RBC
Fig. Schematic of loading by chemical perturbation of
membrane.
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8. PRESWELL METHOD
RBC
0.6% W/V NaCl
Swelled
RBC
5 min incubation
at 0ºC
Drug+loading
buffer
Loaded
RBC
Incubation
25ºC
Resealing
buffer
Resealed
RBC
Fig. Preswell dilutional haemolysis
HYPO-OSMOTIC LYSIS
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9. DIALYSIS METHOD
RBC+phosphate
buffer
Placed in dialysis
bag with air
bubbles
Dialysis bag
is placed in
200 ml of
lysis buffer
with
mechanical
rotator for 2
hrs at 4ºC
Loading
buffer
drug
Loaded
RBC
Dialysis bag
packed is
resealing buffer
with
mechanical
rotator for 30
min at 87ºC
Resealed
RBC
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10. Fig. Dialysis method
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11. ENTRAPMENT BY ENDOCYTOSIS
RBC+drug
Buffer containing
ATP,MgCl & CaCl
At 25ºC
Loaded
RBC Resealing
buffer
Resealed RBC
Fig. Entrapment by endocytosis
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12. APPLICATIONS OF RESEALED
ERYTHROCYTES
Erythrocytes as carrier for enzymes,carrier for drugs
and for drug targeting.
Drug targeting to reticuloendothelial system
-Treatment of liver tumors and parasitic diseases.
- Removal of RES iron overload and toxic agents.
Delivery of antiviral agents.
Oxygen deficiency therapy.
Microinjection of macromolecules.
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13. ADVANTAGES OF
ERYTHROCYTES AS CARRIER
Biodegradable.
Isolation is easy.
Non immunogenic.
Prolonged systemic activity of drug.
Reduce adverse effect.
Peptide and enzyme delivery.
DISADVANTAGES
Possibility of leakage of cells and dose dumping module
alter physiology of cell.
They are removed in vivo by RES so may cause
toxicological problems.
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14. FUTURE PERSPECTIVES
Large amount of valuable work is needed so as to utilise
the potentials of erythrocytes in passive as well as active
targeting of drugs.
Cancer could find its cure.
Genetic engineering.
RECENT DEVELOPMENTS
NOVEL APPROACHES:
Erythrosomes
Nanoerythrosomes
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15. During the past decade, numerous applications have been proposed
for the use of resealed erythrocytes as carrier for drugs, enzyme
replacement therapy etc.
For the present, it is concluded that erythrocyte carriers are “golden
eggs in novel drug delivery systems” considering their tremendous
potential.
CONCLUSION
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16. REFERENCES
1. U.Zimmermann, Jahresbericht der Kernforschungsanlage Julich
GmbH (Nuclear Research Center, Julich). 1973; 55–58.
2. S.P. Vyas and R.K. Khar, Resealed Erythrocytes in Targeted and
Controlled Drug Delivery: Novel Carrier Systems. 2002; 87–416.
3. V. Jaitely, P. Kanaujia, N. Venkatesan, S. Jain, S.P. Vyas, Resealed
erythrocytes: drug carrier potentials and biomedical applications, Indian
Drugs 1996; 33: 589–594.
4. S. Jain and N.K. Jain, “Engineered Erythrocytes as a Drug Delivery
System,” Indian J. Pharm. Sci. 1997; 59: 275–281.
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