Bio-safety in Molecular Diagnostic Laboratory

 Molecular Laboratory must have an
ongoing Bio-safety SOP and also
quality improvement program to
monitor and evaluate objectively and
systematically the quality and
appropriateness of the
information/service it provides
Why do we need safety
 Safe handling of hazard
microorganisms, Chemicals and
 Safe conditions for the work to keep
the tests in right results
Bio-Safety for the Personnel
 Hazard Microorganisms (Risk Group 1 to 4)
 Chemicals
 Radiations
 General Bio-Safety Rules
 Specific Considerations
 Ethidium Bromide,
 Acrylamide,
 UV radiation (Door Glasses)
Specimens are to be handled
to SOPs, with special attention to
any safety precautions
(Laboratory General Bio-Safety)
Hazard Microorganisms
Each detectable organisms must be
classified on its Bio-Safety Level
Risk of Lab. Infections must be
determined for each organisms according
to applied diagnostic tests
Blood-borne and respiratory pathogens
Hazard Microorganisms
 If a dead air UV hood is used, turn on the UV lamp at
least 15 minutes prior to working
 When using a biological safety cabinet (BSC), it must be
on 1/2 hour prior to specimen preparation procedures.
 Working surfaces must be decontaminated prior to
specimen preparation with 10% bleach solution (freshly
made daily) followed by 70% ethanol rinse
 Gloves must be worn at all times for your safety when
handling specimens
Safe conditions for the work
to keep the tests
in right results
Awareness to the Applied Lab.
(provide necessary SOP)
 Specimen
 Defined
preparation area
Flow work and Lab. Design
Receiving samples:
In general, specimens should be received and accessioned in an
area of the facility, that is isolated from testing areas.
 separation and aliquoting of original specimens
 Back up specimens should be kept frozen
at -20oC to - 70oC.
and avoided of freeze-thawing
 Use of sterile container
Patient Specimens and Genomic Materials should be stored separately than
Safe conditions for the work
 Gloves are to be changed frequently, anytime
you contaminate them, whenever a specific
procedure SOP dictates, and never be worn
outside Post Amplification Area, especially in
Pre Amplification Area
 Aerosol barriers tips are used for pipetting into
amplification tubes and pipetting amplification
Other routes of contamination
Contamination of negative specimens
with control specimens
False negative results due to inhibitors
transferring from environment
(Such as Latex gloves….)
and inefficient extraction methods
(Accreditation Protocols)
Molecular Lab.
 Specific flow work and Lab design
Depends on applied Technique
Separation of work areas:
 Pre-Amplification
 Post-Amplification area,
 Storing space
 Specific instruments, materials and other
condition for each area
How contamination can be
Routs of contamination depend on the
 target
 signal
Post-amplification products from previous
analysis can be distributed
 Decontamination
and inactivation protocols for the
test and environment
 Work-benches
and sinks should be decontaminated
each day of use
 Products
must be discard in a safe way
General Consideration in
Designing Molecular Lab.
 Each sample test contains 1010-1012 amplicons,
distributed easily by hand, hair, Lab coat,
 Reagents, materials and instrument can be
contaminated easily
 Complete separation between pre & post
amplification areas must be considered
 Air flow should be from clean area to dirty area
 Special program must be followed if different
PCR sets are being used
 Additional materials recommended to divide in
small sections and stored in separate space
from PCR Lab
General Rules
 Each Working space must have positive
pressure in Pre-Amplification Area
 Transferring reagents, materials, and any
instrument must be avoided from dirty area to
clean area
 Lab coat and gloves must be replaced before
entering to the clean area
 Necessary material must be kept at each lab
 Each lab must have UV, Bleach (10%)
Preparation Lab
 Preparation Lab is the center of the PCR Lab
 Each solution must be checked carefully
 Lab stocks must be divided to small amount
and used one by one in the lab
 Just mixture reaction will be prepared in this lab
without any DNA samples
 Preparation Lab must have its own specific
materials, samplers, buffers, and tube samples
Extraction room
 Any extraction must be carried out under safety
Necessary buffers, and materials must be taken out
from freeze and kept at the room temperature before
It is recommended of two gloves with working of
hazardous specimens
10% bleach are recommended to used for any
probable contamination of centrifuge, safety cabinet,
and so on
Sampler tips must be un-reusable and plug tips
Amplification room
 Thermocycler must be kept in a small
clean area
 Different control negative must be
considered in order to insure the quality
of the test (buffers, primers, dNTP, …)
Detection Lab.
 Test tubes can be opened after amplification
just in Detection room
 To prevent the distribution of amplified products
10% bleach and UV should be available
 It is recommended not to keep the remaining
products after any experiment
 Lab coats and gloves must be removed