Turbid and Nephelometry

Question 1

Physical phenomenon in which a beam of light
changes its direction of propagation (known as
defection) as a result of interaction with sufficiently
small matter particles

Answer 1

LIGHT SCATTERING

Question 2

Change of angle from propagation (incident light)
to its scattering angle

Answer 2

LIGHT SCATTERING

Question 3

Caused by the particles present in the solution

Answer 3

LIGHT SCATTERING

Question 4

Change in direction is known as

Answer 4

deflection

Question 5

2 types light scattering

Answer 5

-elastic
-inelastic

Question 6

In which the wavelength of the scattered light and
incident light is the same

Answer 6

ELASTIC SCATTERING

Question 7

This is what we are concerned in Turbidity and
Nephelometry.

Answer 7

ELASTIC SCATTERING

Question 8

In which the wavelength of the scattered light and
incident light is different or inequal with one
another

Answer 8

INELASTIC SCATTERING

Question 9

The intensity of the transmitted light is measured
and the attenuation of the intensity of incident
light as a result of scattering is measured at the
direction of incident light (i.e., 0°) and compared to
the intensity of incident light (blank measurement)

Answer 9

TURBIDIMETRY

Question 10

In turbidimetry, The intensity of incident light is

Answer 10

attenuated

Question 11

In turbidimetry, Intensity of incident light ______

Answer 11

lowers

Question 12

turbidimetry measures

Answer 12

intensity of transmitted light
attenuation of the intensity of incident light

Question 13

Turbidimetry is the indirect measurement of the scattering effect of
the suspended particles and is referred to as
_____________

Answer 13

turbidance

Question 14

In turbidimetry, it is important to ensure that the material (analyte)
being measured _____________ (does not absorb/absorb) light at the
measurement wavelength

Answer 14

does not absorb

Question 15

In turbidimetry, The attenuation (lowering) of intensity is
due to the ______________, and not due to
the absorption.

Answer 15

scattering of light

Question 16

If our suspension is highly turbid, we may
measure it with __________

Answer 16

turbidity.

Question 17

measures low turbid solutions.

Answer 17

Nephelometry,

Question 18

A measure of the decrease
of transmitted incident light beam intensity as a
result of the light-scattering effect of suspended
particles.

Answer 18

Turbidance

Question 19

Measures the decrease in the intensity of
the incident light.

Answer 19

Turbidance

Question 20

In turbidimetric
measurements, turbidity is the measure of the
_____________ in_________ length of a
given suspension.

Answer 20

decrease in incident beam intensity/unit

Question 21

Measures the decrease in the transparency
of the liquid.

Answer 21

Turbidity

Question 22

Turbidance and Turbidity are both caused by

Answer 22

suspended particles.

Question 23

Turbidimetry measures the

Answer 23

the transmitted light

Question 24

Nephelometry, measures the

Answer 24

scattered light detected at 90°

Question 25

Measures the intensity of the scattered light at a 90° angle from the propagation direction of the incident light is measured

Answer 25

NEPHELOMETRY

Question 26

Nephelometry is the (direct/indirect) measurement of the scattering effect of suspended matter

Answer 26

direct

Question 27

More reliable in low turbidity ranges

Answer 27

Nephelometry

Question 28

When the turbidity is measured using a nephelometer, the units of turbidity are called

Answer 28

nephelometric turbidity units (NTUs)

Question 29

nephelometric turbidity units (NTUs) are based on the turbidity generated by primary ___________ standard

Answer 29

formazin

Question 30

a suspension made by mixing solutions of hydrazine sulfate and hexamethylenetetramine in water

Answer 30

formazin standard

Question 31

Other recognized units of nephelometry are

Answer 31

-formazin turbidity (FTU) -the formazin nephelometric unit (FNU)

Question 32

FACTORS AFFECTING LIGHT SCATTERING

Answer 32

● Concentration of scattering particles suspended in the medium ● Size distribution of scattering particles ● Shape, orientation, and surface condition of the scattering particles ● Refractive index of the scattering particles ● Refractive index of the suspension medium ● Wavelength of the light source employed

Question 33

APPLICATIONS

Answer 33

-Concentration determination of solutions and/or suspensions -Measurement of the degree of turbidity -Determination of weight-average molecular weight and dimensions of polydisperse systems -Measurement of immunoassay’s reaction kinetics or kinetics of immunoprecipitations (application of rate nephelometry) -Monitoring of cell and bacteria growth -Particle size distribution determination

Question 34

how fast is the reaction kinetics; formation of turbidity against time

Answer 34

Rate nephelometry

Question 35

associate to antigen-antibody complexes, or their agglutination reaction

Answer 35

Immunoprecipitations

Question 36

Widely used for vaccine components assays and/or quantitation of components in blood serum

Answer 36

RATE NEPHELOMETRY

Question 37

Used for host cell protein qualification in recombinant biopharmaceuticals

Answer 37

RATE NEPHELOMETRY

Question 38

Used to calculate the amount of antigen (Ag) or antibody (Ab) responsible for the immunological Ab-Ag precipitation reaction or agglutination reaction

Answer 38

RATE NEPHELOMETRY

Question 39

Used in “particle-enhanced immunoassay” where antigens under consideration are linked covalently or absorbed to polymeric microspheres to increase the scattering efficiency.

Answer 39

RATE NEPHELOMETRY

Question 40

When antigens would cause very small intensity (due to the low intensity of the scattering of light), you can combine it with

Answer 40

polymeric microspheres

Question 41

RATE NEPHELOMETRY Can determine concentration of antigen or antibody component based on the formation of

Answer 41

precipitate.

Question 42

Combines the technology of 90° nephelometry and turbidimetry

Answer 42

Ratio turbidimeter

Question 43

Also measures light transmitted directly through the sample

Answer 43

Ratio turbidimeter

Question 44

The benefit of using a ratio turbidimetric system is

Answer 44

the measurement of stray light becomes negligible

Question 45

Used in determination of turbidity of colored suspensions

Answer 45

Ratio turbidimeter

Question 46

light source of ratio turbidimeter

Answer 46

tungsten lamp or infrared light emitting diode for eliminating the color effect

Question 47

Ratio turbidimeter light source for for colored suspensions

Answer 47

Tungsten lamp

Question 48

Ratio turbidimeter light source used to eliminate the effect of the colors

Answer 48

Infrared light-emitting diode

Question 49

The of detectors are

Answer 49

silicon diodes and photomultipliers

Question 50

Nephelometry instrument wherein there is significant improvement in signal-to-noise ratio at very low detection levels

Answer 50

Laser Nephelometry

Question 51

Higher intensity of light →

Answer 51

improve signal-to-noise ratio,

Question 52

The high power density of the laser beam gives rise to the _________ scattered intensity from smaller particles

Answer 52

higher