1. Bio Assay of
NAKE VENOM
J.S.K. NAGARAJAN,
ASST. PROFESSOR,
JSS UNIVERSITY,
(OFF CAMPUS, JSS COLLEGE OF
PHARMACY),
OOTY- 643 001.
email: nagasaki2001@rediffmail.com
Ph: 09443149945

3. The Venom
LD50 of 0.25- 10 to 15 mg is
0.32 mg/kg deadly to a human
adult
One bite
delivers 100- Contains
120mg on Calciseptine
average Toxin 1
Maximum 400 Toxin K
mg

4. Toxins in Venom
Most snakes have multiple types of
venom.
• Cobras have both a short and long
neurotoxin as well as a cardiotoxin.
• Kraits: 3 different types of neurotoxins.
• Sea snakes: Neurotoxin as well as 2
Blood toxins (one causes lysis blood
cells, the other is an anti-coagulant).
• Mambas have only Fasciculin.

5. Mode of Action
These snake neurotoxins act on the
neuromuscular junction (next slide) and
block neuromuscular transmission.
• Fasciculin interferes with this process by
binding to Acetylcholinesterase (AChE).
• Cobratoxin binds to the Acetylcholine
receptors on the muscle cell.
• Result: “Death by respiratory paralysis”.

6. Neuromuscular Junction
Vesicles containing
Acetylcholine (ACh)
ACh receptors
Acetylcholinesterase (AChE)

7. VIPER VENOM
Viper Venom is the dried secretion obtained
from the poison glands of Viperae russelli and
other species of Viperae.
Ppn: Extraction
Drying (freeze)
Dissolving ( WFI)
Filter(bacteria free)- STOCK
SOLUTION
Dilution (to give req. no. of Mouse unit/ml)
Distributed in single dose.
Dried and seal.
NOTE: Mouse Unit/ml: Quantity in mg of
the venom which will kill in 2-24hrs NLT 3 &
NMT 8 mice.

8. Anti Snake Venom
• ASV is prepared by hyperimmunising
horses against venoms of snake.
• It neutralises the free, unbound
venom & to some extent also
dissociates the bound toxin

9. 1 ml of ASV neutralises
• Cobra – 0.6 mg
• Common krait – 0.45mg
• Russels viper – 0.6 mg
• Saw scaled viper – 0.45 mg

10. Assay
Test Animals: 10 Mice ( 18- 20g)
Dissolve(Equiv. 50 Mouse Unit)25 ml of Saline
Inject 0.5 ml IV into each mice
Observe the animals for 24 hours.
Result: NLT 3 & NMT 8 mice die in 2 - 24
hrs .
If the number of deaths is not within the range
Change the dilution of the venom suitably.
Express result in terms of Number of Mouse
Units/mg.

12. THE END