Automation

1
Automation
Kefaya EL- Sayed Mohamed
Prof. of Clinical Chemistry, Mansoura University
2
Automation

• Implies a self regulating process with an
  element of feed-back which detect any tendency to
  malfunction and readjusts the equipment so that
  it continues to function correctly.

3
Definitions and processing concepts
Continuous flow analyser

• The reagent are pumped continuously by syring
  pump
• The samples are introduced at regular intervals
• The flow is segmented to separate one specimen
  from anothor
• This type is used as batch analyzer e.g technicon
  .
• Two types

1. single channel continuous flow analyse one
   constituent in each specimen .
2. Multichannel continuous flow determination of
   several components in each sample

4
Discrete analyser

• Samples are processed in separate reaction tubes.
  
• The instrument contain a variety of receptacle in
  which the sample and reagents are mixed.
• The reaction occurs cuvettes, dry film slides.
• Some containers contain the reagents and only the
  specimen need to be added.
• Others add both reagents and specimen.

5
Reaction vessels and cuvets in discretes

• Reused or discarded
• Used as cuvet or just reaction tube, aspirated in
  tube then to another tube for measurement

For wash reused reaction vesseles or cuvets

• aspiration of the reaction mixture
• a detergent ,alkaline or acid wash soln . is then
  dispensed into and aspirated out of the cuvets

6
Parallel analysis

• All specimens are subjected to a series of
  analytical processes at the same time in a
  parallel fashion

• Discretionary multiple channel analysis.
• The specimen can be analyzed by any one or by
  more than one of the available processes
  (methods, channels).

7

• Batch analyzer.

- A number of specimens are processed in the
same analytical session , or run
8
(No Transcript)
9
The components steps in automated system

1. Specimen identification.
2. Specimen preparation.
3. Specimen handling, transport and delivery.
4. Specimen processing.
5. Sample transport and delivery.
6. Reagent handling and storage.
7. Reagent delivery.
8. Chemical reaction phase.
9. Measurement approach.
10. Signal processing data handling and process
    control.

These operations are usually performed
sequentially but in some instrument, they may be
combined and occur in parallel.
10
Specimen identification
11
Specimen Preparation
12
Specimen Handling, Transport and Delivery
13
Specimen processing
14
Sample transport and delivery

• In continuous flow system the sample is
  aspirated through the sample probe into
  continuous reagent stream
• In Discrete analyzers the sample is aspirated
  into sample probe and delivered, with reagent
  into reaction tube or cup .

15
Carry over

• Carry over occurs when a previous sample or
  reagent contaminates successive tests in a run
  causing the next sample to have an aberrantly
  higher or lower results .
• Carry over occurs when anlytes occur in extremely
  high levels e.g. enzyme or h CG in pregnancy
• Carry over also occurs in systems that reuse
  cuvettes that are insufficiently washed after
  each testing cycle.

In discrete systems with disposable reaction
vessels and measuring cuvettes carry over is
caused by the pipeting system
16
(No Transcript)
17
(No Transcript)
18
(No Transcript)
19
(No Transcript)
20
(No Transcript)
21
Disadv one analyte per rotor but now recent
models allow multiple analysis 24 rotors can be
loaded at one time.

• In Continuous flow by glass coils passing
  through the samples and reagents.

22
Measurement approaches

• Spectrophotometry
• Fluorimetry e.g. IMX
• Chemiluminescenc e.g. IMMULITE
• Electrochemical for electrolytes

23
Examples
24
(No Transcript)
25
Automated immunoassay systems differ from
chemical analyzers in that they require the use
of

1. solid phase reagents to separate bound and
   unbound
2. More sensitive detection methods e.g fluorescence
   and chemiluminescence
3. Special handling of the reagents

e.g.

1. Thermal conditioning to keep chemilum substrate
   stable.
2. Constant agitation to keep microparticles
   suspended.

26
Automated immunoassay
4-Multiple Calibrators (upto 6)

• Calibration usually nonlinear

Example ACS 180

• benchtop
• R-A
• Imm . AS.S ay

IMMULITE

• bench top
• R-A
• Imm. Assay

27
Selection of instruments

• Role of an automated system in the workflow of
  the laboratory.
• Identification of candidate system (RA or batch).
• Cost effectiveness of the system.
• User-friendiness (interface between the machine
  and the human operator).
• Analytical performance.

28
Advantages of automation

• Large number of samples may be processed with
  minimal technician.
• Two or more methods may be performed
  simultaneously.
• precision is superior to that of manual
  performance.
• calculations may not be required.

29
Disadvantages of automation

• limitation of the methodology "closed system".
• Expensive.
• Many systems, are impractical to use for small
  numbers of samples. Therefore, back up manual
  methods may be required for individual emergency
  analysis. Back up methods must also be available
  in the event of instrumental failures.

30
Thank you