4. -Electrolytes are positively and negatively
charged molecules called ions, that are found
within the body's cells and extracellular
fluids, including blood plasma.
-Electrolytes play multiple roles in the
maintenance of body functions:
1-They sustain osmotic pressure which
control fluids distribution in the body (related
to sodium level
5. 2-Maintain proper body Ph .
3-Regulate the function of the heart and
4- Assist in electron transfer reactions.
5- Participate in enzymatic reactions .
Some of the disorders associated with
electrolyte imbalances include:
6. 1-Congestive heart failure.
2-Respiratory alkalosis (occurs when
blood pH falls above 7.35 and acidosis
occurs( when blood pH falls below 7.35
3-Diabetes insipidus (water loss by the
4-Gastrointestinal and kidney diseases.
5-overhydrationn and dehydration.
(When water loss is greater than intake, or
7. -Doctors refer to a low electrolyte level with
the prefix “hypo_” and to a high level
With the prefix “hyper_”.
-Because abnormal electrolyte levels can
result from or cause various disorders,
their analysis is a key factor in patient
diagnosis and treatment.
-Electrolyte Analyzers measure these
electrolytes in serum, plasma and urine.
8. ELECTROLYTE PANEL
Electrolyte analyzers measure electrolyte
concentrations in body fluids - typically
whole blood, plasma, serum, or urine
Electrolytes typically measured by an
Electrolyte Analyzer are called the
“Electrolyte Panel” which consists of:
- Sodium (Na+)
- Potassium (K+)
- Chloride (CL+)
9. -Calcium, the most abundant mineral in
the body, is also measured by many
electrolyte analyzers. The concentration
of ionized calcium (Ca++), total calcium,
or both can be measured in the same
body fluids as electrolytes.
-Sodium is the principal extracellular
cation and potassium the principal
intracellular cation. A cation is an ion
with a positive charge.
Anions have a negative charge.
11. AlD(1) Micro_ DC
12. 1-what analyte you want to measure ?
The external reference electrode and
measuring electrode are exposed to the
unknown sample solution, potential of
the sample solution is measured
relative to the external reference.
2- Buffering the voltage generated by
ion selective electrode by operational
3- Analong multiplexer selecting signal.
13. 4- An (AlD 1) converter for converting the
signal into digital domain .
5- Micro-processor based computer
control mechanical functions of the
6- Digital display for showing results
and displaying messages and questions
7- The motor driver turns drives D.C
8- D .C motor drives the Peristaltic
14. 9-Bubble detector verifies the presence
of air or fluid in the sample tubing.
10-An (AlD 2) converts the bubble
detector reading into digital form to
16. Flame Emission Photometry
Flame photometry can be used to measure
Na+, K+, and lithium Li+ .This method is
based on the fact that some metallic
elements absorb thermal energy, exciting
their electrons to a higher energy state .As
the electrons return to the stable ground
state, they emit photons light at
wavelengths characteristic of the particular
element and at intensities proportional to
the element’s concentration.
17. The concentration of the test solution
is determined by comparing its signal
with that obtained for standard
18. There is a different colored filter for -
each analyte measured
-The output of the photo-detector is
directly proportional to the
concentration of the analyte being
-The brighter the flame (in that
wavelength the greater the
concentration of the analyte
19. -There is a different colored filter
for each analyte measured.
• Sodium is yellow with a
wavelength of about 590 nm
• Calcium is red with a wavelength
of about 640 nm
• Potassium is blue with a
wavelength of about 490 nm
20. • Lithium is dark red with a wavelength
of about 710 nm
The output of the photodetector is -
directly proportional to the
concentration of the analyte being
-The brighter the flame in that
wavelength, the greater the
concentration of the analyte
Each analyte emits a specific color
21. Reported problems
Flame photometry measurements can be
compromised when insufficient attention
is paid to maintenance procedures,
optimal flame size, and aspiration rate .In
addition, a warm-up period is usually
required to stabilize the system .Because
of the gas used to fuel the system, flame
photometry systems should be used in a
22. Problems can arise when results from
methods using direct measurements
undiluted specimens are compared with
those from methods using indirect
measurements diluted specimens .Flame
photometry provides an indirect
measurement of total concentration,
particularly in Na +and K +analyses, while
ISE methods provide direct measurements
of activity .
25. Principles of operation
This method measures the voltage that
develops between the inner and outer
surfaces of an ion selective electrode.
Most electrolyte analyzers use ISE
methodology in which measurements
of the ion activity in solution are made
potentiometrically using an external
reference electrode and an ISE
containing an internal reference
27. The external reference electrode and
ISE are exposed to the unknown
sample solution, and the potential of
the sample solution is measured
relative to the external reference
As the specific ions under .electrode
analysis are selectively bound to the
ISE, the internal reference electrode
detects the potential difference
between an internal filling solution
and the sample solution potential
28. between the external reference
electrode and the ISE, which is a
function of the specific ion’s activity
concentration, is amplified and liter
L displayed in millimoles per liter
The ISE system is calibrated with
solutions containing known
concentrations of analytes; the
concentration of an unknown
solution is derived by comparing
its potential with that of a solution of
known concentration .
29. Samples can be diluted before analysis
“indirect method” or analyzed without
dilution “direct method.”
Different types of ISEs provide
measurements for specific analytes .The
Na-+sensitive electrode is made of glass
specially formulated to provide high
selectivity for Na .+The K-+sensitive
electrode consists of polyvinyl chloride
PVC impregnated with valinomycin, an
antibiotic that is selective for K .+The Cl--
30. electrode consists of a liquid membrane
containing quaternary amines, which are
selective for chloride ions, in a PVC
support .A calcium ISE uses an ion
selective calcium sensor that consists of
either a neutral membrane PVC
impregnated with uncharged calcium
selective organic molecules dissolved in a
plasticizer or a negatively charged
membrane PVC impregnated with an
31. Some errors observed when using ISEs
occur because of proteins coating the
membranes, lack of selectivity , or
contamination with ions that compete
with selected ion.
Calibration standardization has been
recommended to minimize deviations
among different ISE analyzers.
34. ELECTROLYTE ANALYZER
• Refers to the Cal and Slope standards
and the Wash solution.
• Cal and Slope solutions are two
calibration fluids of different
concentrations used during a Two Point
Calibration more on that later.
35. • Wash solution may also be
referred to as a flush or rinse
solution and does just what it
implies, it cleans and rinses the
tubing after each analysis.
2 -Electrode Module
• Also referred to as a Flow Cell or
• Houses the:
37. *Air Fluid Detector
• Located at the entrance or exit of the
• Verifies the presence of air or fluid in
the sample tubing.
– A small light source shines through the
tubing into a photodetector.
–The photodetector is monitored by the
μP which monitors the air/fluid detector
so it knows when to start and stop.
39. Reference Electrode
• Supplies a continuous electrical
potential that is used as a reference to
measure the electrical potential
produced by each ISE.
• Constant 756 mV potential
40. 3-Peristaltic Pump
• Pushes the reagent fluids and
patient sample through the tubing to
the sample probe and Electrode
Module out to the waste bottle.
• Fluid is drawn into the analyzer as
the flexible tubing is pressed by the
rollers of the pump and drawn
through the tubing via the squeezing
action of the rollers on the tubing.
41. • Peristaltic Action
• Aspirates fluids into the analyzer
via the peristaltic pump.
• The probe accepts fluids in the
STAT position up or Automatic
42. -Performed with the probe in the up position
-The probe accepts a handheld sample for a
44. - Performed with the probe in the
-The probe automatically accepts
samples from a test tube or a
cuvette in a tray or carousel.
-This is the position of the probe
during normal operation.
46. TWO POINT CALIBRATION
-A ‘Two Point Cal’ is a full calibration
usually run on a daily basis that
establishes the calibration and slope for
-Two standards of known analyte
concentrations are analyzed.
-Each electrode measures the analyte
concentration in both standards in order
to obtain the electrode’s slope
47. ONE POINT CALIBRATION
-Used to monitor and correct the
instrument for electrode drift.
• Electrode drift is a gradual change in
electrode potential that can adversely
affect electrode performance.
-Normally performed prior to every
analysis and involves just running the
cal standard through the instrument.
The electrolyte analyzer must match
the facility’s present and future
testing requirements and
Several performance features can
be used to assess accuracy and
reliability, including the following:
49. • Analytical range.
The concentration range over which an
instrument can measure a particular
Purchasers should check these values
carefully under conditions in their own
laboratories because actual ranges
may vary significantly from those
stated by the manufacturer
50. • Linearity. The linearity of an analyzer
determines how accurately the unit can
measure analyte concentration over a
certain concentration range as determined
against a given control or standard.
Instruments with large linear ranges can
analyze samples with awide range of
analyte concentrations without diluting or
manipulating them in any way. This feature
provides a faster turnaround of results and
may save operator time if dilutions must
be manually performed.
51. • Specificity. This is the ability of an
instrument to measure only the
analyte selected. In electrochemical
analyzers, this is a function of
electrode design and construction
• Precision .A high degree of
precision, which is a measure of
how closely a test result can be
reproduced, not only provides a
more sensitive determination
of changes in the patient’s
52. but also reduces the need for duplicate
testing to verify the accuracy of initial
test results .Precision is expressed
numerically in terms of the coefficient
of variation CV, with a small CV
indicating a highly precise instrument.
• Stability. Analyzers that give readings
with a high degree of precision for
extended periods of use have very stable
calibration curves. These units may be
less costly to operate than analyzers with
more labile curves because.
53. they do not require recalibration
as often; the unit thus uses less buffer
and control and runs fewer non
patient analytical tests
• Carryover .Residue left over on an ISE
from a previous sample is called
carryover .This results from incomplete
cleaning of the electrode with the wash
solution .Carryover can cause
erroneously higher or lower readings in
samples and result in unnecessary
54. • Downtime .Downtime occurs when
the analyzer is undergoing routine
maintenance or is shut down for
troubleshooting and repairs .A unit
that requires frequent maintenance
or has a poor reliability record cannot
consistently handle a normal
workload and will cost the laboratory
money to service (even with a good
service contract )and to compensate
for lost testing revenue .Under these
circumstances, a reliable backup
analyzer is a necessity.
55. Technical features
• Equipment Interface 4 line, 128 × 64 dots
LCD display with backlight and three keys.
• Analysis principle Direct “Flow Thru” Ion
selective electrodes (ISE).
• Sample volume 100μl .
• Sample type Whole Blood, Serum, Plasma,
• Sample Application From Syringe, Sample
Cup, Capillary or Collection Tube.
56. • Throughput 60 samples/hour
without printout, 50 samples/hour
• Calibration Automatic two-point
calibration with additional option for
carrying out one-point and two-point
57. • Normal Reference Range Users can adjust
reference range for all parameters according to
their requirements. Flagging of abnormal
samples provides easier analysis.
• Display 128 × 64 Dot LCD display with
• Printer Built in Stationary Head
Graphical Thermal Printer.
58. • Storage Capacity Patient Result: 250 samples.
• Interface port RS 232 Interface.
• Power Voltage: 165-250 V, 50 Hz; Power < 35VA.
• Dimensions 300(H) × 350(W) × 230(D) mm.
• Weight 6 Kg approx.
• Operating environment.
• Temperature 15° to 40°C.
• Relative humidity 20%~ 80%.