Unit 1 Flashcards
1
Q
A quantitative science that is concerned with measurement of amounts of biologically important substances (analytes) in body fluids.
A
CLINICAL CHEMISTRY
2
Q
__________________ are analyzed in the laboratory while the substances in them (________) are measured and quantified
A
specimens or samples are analyzed in the laboratory while the substances in them (analytes) are measured and quantified
3
Q
When an individual test is not sufficient to assess the medical condition of the patient, combination of several test may be used, which is known as
A
“Panel or profile”
4
Q
CATEGORIES OF FASTING PLASMA GLUCOSE:
FPG 70-99 mg/dL (3.9-5.5 mmol/L)
A
Normal fasting glucose
5
Q
CATEGORIES OF FASTING PLASMA GLUCOSE:
FPG 100-125 mg/dL (5.6-6.9 mmol/L)
A
Impaired fasting glucose
6
Q
CATEGORIES OF FASTING PLASMA GLUCOSE:
FPG ≥ 126 mg/dL (≥ 7.0 mmol/L)
A
Provisional diabetes diagnosis
7
Q
True or false
Impaired fasting glucose is not a clinical entity but an indication that the patient is at risk of having diabetes mellitus
A
True
8
Q
True or false
Provisional diabetes diagnosis means the patient has diabetes mellitus
A
True
9
Q
purpose of a Clinical Chemistry Laboratory
A
to facilitate the correct performance
of analytic procedures.
10
Q
True or false
It is the role of the medical laboratory scientist/medical technologists to produce results with utmost accuracy and reliability
A
True
11
Q
True or false
Achievement of accurate and reliable results is anchored into the idea that medical technologist is able to understand fundamental concepts critical to any analytic procedures
A
True
12
Q
Two components of a quantitative laboratory result
A
Actual value
Unit of expression
13
Q
describes the numeric value
A
Actual value
14
Q
describes the physical quantity or dimension (e.g.
mass, volume, length or time)
A
Unit of expression
15
Q
■ Adopted internationally in 1960
■ Preferred in scientific literature and
clinical laboratories
■ Based on metric system
■ The ONLY system used in many
countries
A
Système Internationale d’Unités (SI)
16
Q
Seven basic SI units
A
Length
Mass
Time
Electric Current
Thermodynamic Temperature
Amount of substance
Luminous intensity
17
Q
● from the mathematical derivation of one of basic units
● Katal is derived from SI units, mole and second
■ Expressed as mol/s
A
SELECTED DERIVED UNITS
18
Q
SELECTED DERIVED UNITS
A
Frequency
Force
Celsius temperature
Catalytic activity
19
Q
● Widely used and become acceptable for use with basic SI units and selected derived units
● Commonly used and also accepted as one of the SI units
A
SELECTED ACCEPTED NON-SI
20
Q
SELECTED ACCEPTED NON-SI
A
Minute(time)
Hour
Day
Liter(volume)
Angstrom
21
Q
PREFIXES USED WITH SI
A
atto
Femto
Pico
Nano
Micro
Milli
Centi
Deci
Liter/meter/gram
Deka
Hecto
Kilo
Mega
Giga
Tera
Peta
Exa
22
Q
____________ in the containers are already prepackaged as a unit . These may require addition of water or buffer to the solid or powder prepackaged reagent
A
Reagents
23
Q
Varying grades of purity
Analytic reagent grade (AR) and ultrapure
○ Best for lab use
A
Chemicals
24
Q
CHEMICALS USED FOR REAGENT PREPARATION
A
Analytic Reagent (AR) Grade
Ultrapure Reagent
Chemically Pure (CP)/ Pure Grade
Technical/ Commercial Grade
25
● Important of quantitative and qualitative analysis
● For trace metal analysis and preparation of standard solution
○ Used for calibration of instruments
● Must meet specifications set of the American Chemical Society (ACS)
● Must have labels with the initials AR or ACS or the term For laboratory use or ACS Standard-Grade Reference Materials
○ If these labels are printed in the storage containers, it means that the chemical is analytic reagent
Analytic Reagent (AR) Grade
26
● Put through additional purification procedures
● For use in specific procedures such as chromatography, atomic absorption, immunoassays, and molecular diagnostics
● Labels – with designations of HPLC (high performance liquid chromatography) or chromatographic
Ultrapure Reagent
27
● Impurity limitations are not stated and preparation is not uniform
● Not recommended for research & analytical chemistry
● Purity is assessed by measurement of melting point or boiling point
○ Since impurity limitations are not stated
Chemically Pure (CP)/ Pure Grade
28
● Primarily used in manufacturing
● Should never be used in the clinical laboratory
● United States Pharmacopoeia (USP) and National
Formulary (NF)
○ Drug manufacturing
Technical/ Commercial Grade
29
A major source of safety information for employees
MATERIAL SAFETY DATA SHEET (MSDS)
30
A major source of safety information for employees
MATERIAL SAFETY DATA SHEET (MSDS)
31
Requires that all employees have a right to know all about the chemical hazards present in their workplace
OSHA Federal Hazard Communication Standard
32
Information contained in an MSDS
● Physical and chemical characteristics
● Fire and explosion potential
● Reactivity potential
● Health hazards and emergency first aid procedures
33
Who is responsible in providing a copy of the MSDS to the purchasing laboratories or units
Chemical Manufacturer
34
- Solution containing known concentration of a
particular chemical or analyte
- Used to calibrate instruments used for colorimetric, electrochemical, turbidimetric, & other analytical measurements
- Used to calibrate instruments in any analytic procedure
STANDARD SOLUTION/ STANDARDS
35
● Highly purified chemical that can be measured directly to produce substance of exact known concentration & purity
● American Chemical Society (ACS) purity tolerances –100 ±0.02%
PRIMARY STANDARD
36
certified the use of standard reference materials (SRMs) instead of ACS primary standards
National Institute of Standards and Testing (NIST)
37
Substance of lower purity, with its concentration determined by comparison with primary standard
SECONDARY STANDARD
38
two (2) organizations providing guidelines for proper chemical selection and reagent preparation
○ College of American Pathologists (CAP)
○ Clinical and Laboratory Standards Institute (CLSI)
■ Formerly the National Committee for Clinical Laboratory Standards (NCCLS)
39
most frequently used reagent in clinical laboratory
Water
40
It is used:
- To prepare reagents
- As diluent for controls and standards
- To flush and clean the internal components of analyzers or of instruments in the Clinical Chemistry laboratory
- To wash and rinse laboratory glassware (cluster purity)
-For most of uses, water must be of highest purity
-The water required for rinsing laboratory glassware can be of lesser purity
Water
41
True or false
Labs use reagent grade water
True
42
6 types of reagent grade water (CLSI):
Clinical laboratory reagent water (CLRW)
Special reagent water (SRW)
Instrument feed water
Water supplied by method manufacturer
Autoclave and wash water
Commercially bottled purified water
43
Water specification:
○ For test methods or analytical procedures
requiring minimum interference
Type 1
44
Water specification:
■ Hematology, Microbiology, Immunology, and
Chemical analysis
■ Reagent, quality control, and standard
preparation
Type 2
45
Water specificqtion:
■ UA (urinalysis), Parasitology, and Histology
■ Glassware washing
Type 3
46
MONITORING WATER PURITY
Resistivity - > 10 MΩ (megaohms)
Bacterial content (count)
pH
Silica Content
Organic contaminants
47
uses activated charcoal to remove organic materials and a submicron filter or a filter that would remove substances larger than the filter’s pores
Prefiltration
48
This method is the oldest method of water purification
Distillation
49
- Uses pressure (high pressure) to force water through a semi permeable membrane
- Like distillation method, it does not produce type 1 water alone but if additional filter (ion exchange and carbon filters) are added to the system, a type 1 water may be produced
Reverse osmosis
50
This method uses bead-like resin materials (ion
exchange resins (cation resin and anion resin))
Deionization
51
True or false
A reagent grade water can be obtained by initially filtering it to remove particulate matter (prefiltration), followed by reverse osmosis, deionization, and a 0.2 mm filter or more restrictive filtration process
True
52
True or false
Glasswares used in heating during experiments are more prone in breakage.
True
53
True or false
Knowing the usage of the different glasswares helps in preventing breakage.
True
54
TYPES OF GLASSWARE
Borosilicate Glass
Corex
Vycor
Low Actinic Glass
Standard Flint Glass
55
Types of glassware:
● Most common type of glassware in volume measurement.
● High degree of thermal resistance, has a low alkali content, and free from the magnesium-lime zinc group of elements, heavy metals, arsenic, and antimony.
o Example: Pyrex and Kimax
Borosilicate Glass
56
Types of glassware:
● A special alumina-silicate glass that has been strengthened chemically rather than thermally.
● Characterized by a high degree of chemical resistance.
● 6 times stronger than borosilicate.
Corex
57
Types of glassware:
● Recommended use for applications involving high temperature, drastic heat shock, and extreme chemical treatment with acid and alkali.
● Acid and alkali resistant.
Vycor
58
Types of glassware:
● High thermal resistance
● Amber or red color added as an integral part of the glass.
● Gives maximum protection to light sensitive material (bilirubin)
o Reagent bilirubin can be placed in a low actinic glass.
o Commonly used to store control material and
reagents
Low Actinic Glass
59
Types of glassware:
● Made up of soda-lime glass and a mixture of calcium, silicon, and sodium oxides.
● Poor resistance to high temperatures.
Standard Flint Glass
60
TYPES OF PLASTICWARE
Polypropylene
Polyethylene
Polystyrene
Teflon
61
Types of plasticware:
● Flexible or rigid, is chemically resistant, and can be autoclaved.
● Used in the manufacturing of plastic pipet tips, specimen tubes, and test tubes.
o Usually used in the Clinical Microscopy.
● Can withstand temperatures down to -190 degree
Celcius.
Polypropylene
62
Types of plasticware:
● Used in the manufacturing of test tubes, bottles, graduated ubes, stoppers, disposable transfer pipette, volumetric pipette, and test tube racks.
Polyethylene
63
Types of plasticware:
● Used to manufacture capped graduated tubes and test tubes.
● Rigid, clear type of plastic which should not be autoclaved
● WIll crack and splinter when crushed
● Not resistant to hydrocarbons, ketones, and alcohols
Polystyrene
64
Types of plasticware:
● For manufacturing stirring bars, tubing, cryogenic vials, and bottle cap liners
● -270 degree Celcius to +255 degree Celcius
● Resistant to a wide range of chemical classes
Teflon
65
Most commonly used in measuring or graduated pipette in Clinical Chemistry
Serologic and Mohr Pipette
66
VOLUMETRIC LABORATORYWARE
TYPES ACCORDING TO DESIGN:
To Contain (TC)
To Deliver (TD)
67
● Contains necessary volume but do not deliver exact volume, due to tendency of fluids to cling to glass surface
o Holds/contains particular volume but does not
● dispense the exact volume
● Often referred to as rinse-out pipet
● Sahli hemoglobin and Lang-Levy pipette
To Contain (TC)
68
● Will deliver the exact volume
o Dispenses exact volume into the receiving
vessel o Small amount left in the tip should
not be blown out
● Mohr, serologic and volumetric pipets
To Deliver (TD)
69
VOLUMETRIC LABORATORYWARE
TYPES ACCORDING TO DRAINAGE
CHARACTERISTICS
Blowout Pipette
Self-draining Pipette
70
● Has a continuous etch ring or two small, close, continuous rings located near the top of the pipette.
● Last drop of liquid should be expelled into the receiving vessel
Blowout Pipette
71
● No etched rings or markings.
● Allow the content of the pipette to drain gravity.
Self-draining Pipette
72
VOLUMETRIC LABORATORYWARE
TYPES ACCORDING TO PURPOSE:
Measuring or Graduated pipette
Transfer Pipette
73
(Measuring or Graduated pipette)
does not have graduation to the tip; self-draining pipette, but tip should not be allowed to touch vessel while piper is draining.
Mohr Pipette
74
(Measuring or Graduated pipette)
has graduation marks to the tip; a blowout pipette.
Serologic Pipette
75
(Measuring or Graduated pipette)
total holding volume of less than 1 ml; may be designed as either Mohr or Serologic Pipette.
Micropipette:
76
Designed to dispense one volume without further subdivision
Transfer Pipette
77
(Transfer Pipette)
▪ Bub-like enlargement near the tip of pipette stem.
▪ for biologic fluids having a viscosity greater than water.
▪ a blowout pipette
Oswald-Folin
78
(Tranfer Pipette)
▪ Has bulb enlargement midway In stem of pipette, near upper tip.
▪ To dispense or transfer aqueous solutions.
▪ A self-draining; used when diluting standards, calibrator, or quality control material.
Volumetric Pipette
79
(Transfer Pipette)
▪ Does not have calibration marks
▪ Used to transfer solution or biologic fluids without consideration of a specific volume.
Pasteur Pipette
80
(Transfer Pipette)
▪ Fixed volume: pipette associated with only one volume
▪ Variable: able to select different volume
Automatic Pipette
81
Type of automatic pipette that relies on piston for suction draw to draw the sample into the disposable tip and must be changed after use.
Air-displacement
82
Type of automatic pipette that operate like a hypodermic syringe, does not require a different tip for each use unlike for air- displacement pipette.
Positive-displacement
83
automatic pipette that collects liquid from a common reservoir, and dispenses it to the receiving vessel.
Dispenser and diluter
84
(TYPES OF THERMOMETER)
use a colored liquid (red etc.) or mercury in plastic or glass material with a bulb and a graduation scale.
Liquid-in glass thermometers
85
(Types of Liquid-in glass thermometer)
immersed to the proper height or defined depth indicated in the thermometer.
■ Use to heating blocks and water baths
Partial immersion
86
(Types of Liquid-in glass thermometer)
they have a bulb and the entire column of the liquid should be immersed to the medium being measured.
■ Use to: Refrigerators and freezers.
Total immersion
87
(Types of thermometer)
It converts changes in temperature into resistance (transducer)
Electronic thermometer/thermistor probe
88
(Types of thermometer)
a fast and easy thermometer that is used today. Used in clinical laboratories today
Digital thermometer
89
● Most commonly used method of separating solid matter from a liquid suspension
● Uses centrifugal force
● A process in which centrifugal force is used to
separate solid matter from a liquid suspension.
● Most commonly used separation technique in
laboratory
Centrifugation
90
Refers to the centrifugal force generated
○ Depends on the three important variables (mass, speed, and radius)
Relative Centrifugal Force (RCF) or Gravity (g)
91
(Types of centrifuge)
- Also known as Swinging Bucket Type
- Centrifuge tubes are held in a vertical position when not moving but horizontal when the centrifuge is fully in motion.
- Recommended for Serum Separator Tubes (SSTs)
Horizontal Head Centrifuge
92
(Types of centrifuge)
Has a fixed 25-52° angle at which tubes are held during centrifugation
Angle-Head Centrifuge
93
(Types of centrifuge)
○ Generates the highest speeds among all types
○ Useful for lipoprotein analysis tests
■ High Density Lipoprotein (HDL)
■ Low Density Lipoprotein (LDL)
■ Chylomicrons
■ Very Low Density Lipoprotein Fraction
○ Usually refrigerated centrifuge
Ultracentrifuge
94
UNBALANCED CENTRIFUGE can cause ____________
UNBALANCED CENTRIFUGE can cause VIBRATION
95
Tubes are placed in the centrifuge in a
_____________ position
Tubes are placed in the centrifuge in a
counterbalanced position.
96
True of false
The tubes must be equal in volume and weight.
True
97
● Used only occasionally in labs today
● Paper is folded and fitted into funnel; solution (filtrate) drains through filter into receiving vessel.
Filtration
98
● Popularized in the 1970s
● The process of _________:
○ Solution is put in bag or on one side of semipermeable membrane
○ Larger molecules remain in bag or on one side of membrane; smaller molecules and solvents are diffused out
● A time-consuming technique
● Occasionally performed in labs today
Dialysis
99
Both liquid portion (plasma) and cellular components (red and white blood cells, platelets)
Whole Blood
100
Clear yellow supernatant present in anticoagulated tubes; liquid called fibrinogen (used for clot formation).
Plasma
101
● Remaining liquid after clotting.
● If you utilize a tube without
anticoagulant, yellow fluid that settles on top after centrifugation
Serum
102
To measure or determine blood gasses and pH.
Arterial blood
103
Urine creatinine: example of test utilizing urine sample.
Urine
104
● Collected by lumbar puncture or spinal tap
● CSF Protein and CSF Glucose
CSF
105
Pleural test/s: fluid example
● Pleural fluid cholesterol
● Pleural fluid triglycerides
● Pleural fluid glucose
Pericardial fluid example test/s:
● Detection of the enzyme adenosine deaminase
Peritoneal fluid example test/s:
● Peritoneal fluid glucose
● Peritoneal fluid alkaline phosphatase
● Peritoneal fluid amylase
Amniotic fluid example test/s:
● Amniotic fluid bilirubin
Serous fluids
106
Factors to be checked before processing samples
○ Volume considerations
○ Use of appropriate anticoagulants or preservatives
○ Timing
○ Properly transported
107
(3 distinct phases of centrifugation)
● Ideally, all measurements should be performed within 45 minutes to 1 hour.
● Plasma or serum is preferred for most biochemical determinations.
○ Serum: most common specimen of choice
● Plasma: centrifuge blood within 1 hour after collection for 10 minutes at a RCF of 850-1000x gravity.
● Serum or plasma must be stored at 4oC to 6oC
● If analysis is to be delayed for longer than 4 hours.
● Refrigeration is temporary
Pre-centrifugation
108
(3 distinct phases of centrifugation)
● Utilizes centrifuge
● A centrifuge uses centrifugal force to separate phases of suspensions by different densities.
● Centrifuge is most frequently used in processing blood to derive plasma or serum fractions.
● Re-centrifugation of gel separator tubes has been associated with pseudo hyperkalemia.
○ False increase in serum or plasma potassium concentrations
○ One study demonstrated that after initial centrifugation, a new serum will develop under the gel within the cellular layer
Centrifugation
109
(3 distinct phases of centrifugation)
● Serum or plasma should be separated from the cells immediately.
● If analysis is to be delayed, you have to store the sample at If analysis is to be delayed, you have to store the sample at 4oC to 6oC.
Post-centrifugation
110
It is a legal document that describes how evidence is handled from the time it is acquired and through all subsequent examinations and storage.
Chain of custody
111
According to the chain of custody, any individual in contact with the sample must document:
○ Receipt of the sample
○ Condition of the sample at the time of receipt
○ Date and time it was received
112
Minimum Elements of Paper or Electronic Patient Reports:
○ Name and address of laboratory performing the analysis including any reference laboratories used.
○ Patient name and identification number or unique identifier.
○ Name of physician or person ordering the test.
○ Date and time of specimen collection.
○ Date and time of release of results (or available if needed).
○ Specimen source or type.
○ Test results and units of measure if applicable.
○ Reference ranges, when available.
○ Comments relating to any sample or testing
interferences that may alter interpretation.
113
Physiological factors affecting chemistry analytes
Diet
Medication or herbal supplements
Circadian rhythm
Timing of collection
114
Patient preparation factors affecting chemistry analytes
Patient posture
Fasting
24-hour urine collection
115
Collection and sample processing factors affecting chemistry analytes
Venipuncture technique
Tube selection
Tourniquet use
Specimen transport and storage
