Examples of the applications of immobilized enzymes in analytical techniques, automated analysis, biosensors, therapeutics and industries.

1. ANALYTICAL TECHNIQUES
AUTOMATED ANALYSIS
BIOSENSORS
THERAPEUTICS
INDUSTRIES
Applications of
immobilized enzymes

2. Analytical techniques
 enzyme electrodes
 Glucose oxidase
electrode (GOD) –
measure glucose levels in
urine and blood
 Glucose oxidase is
immobilized in a
polyacrylamide gel and
held in place around an
oxygen electrode, by a
piece of cellulose acetate
membrane
O2 sensor
Immobilized
enzyme
Cellulose acetate
membrane

3.  β-D-Glucose +O2 D-Gluconic acid +H2O2
 Oxygen electrode measures the consumption of O2
at a rate, which is proportional to the concentration
of glucose present in the sample.
 Cheaper
 Easy to assemble
 Simple method of estimation of large number of
compounds in solutions, which are even opaque or
particulate.
 Limitation-stability of enzymes used.
Glucose oxidase

4. Automated analysis
 An array of immobilized
enzymes in automated
analyses of a large
number of samples
 eg: blood, urine
 Auto analyzers link a
large number of
immobilized enzymes
and perform multiple
analyses on a single
sample quickly
Eg: Dextrose and Glucose
measurement in baked products,
cereal products, sweetened
condensed milk etc

5. Biosensors
 Biosensors are compact analytical devices
incorporating a biological or biological-derived
sensing element either integrated within or
physically associated with a physiochemical
transducer.
 They convert biological responses into an electrical
signals, which are amplified and measured.
 Analytes
1.014Detector
AmplifierSensing
elements
Reference
Transducer
Display

6.  Biological sensing component-tissue,organ,
microorganism, organelle, cell receptor, enzyme,
antibody, nucleic acid etc.
 Detectors detect biological responses, generated during
interaction between analyte and biological sensing
element.
 Detectors function based on any one of the principles:
 calorimetric - measure heat output
 Potentiometric - measure changes in electrical potentials
 Amperometric - measure movement of electrons in in
redox reactions
 Piezoelectric - measure effects due to mass of the
reactants or products,
 Photometric -measure light absorption/scattering

7.  Uses
 Monitor specific components of beer
 Pollutants in the environment
 Harmful bacteria in the air
 Flavours in food
 Freshness of fishes etc

8. Therapeutic applications
 Enzyme replacement and
enzyme therapies.
 Absence of particular
enzyme due to genetic
malfunction/ tissue
damage build up some
products leading to disease.
 Such diseases are
controlled by injecting
required enzyme in
immobilized form to
prevent immunological
reactions.

9.  In Enzyme replacement, enzymes that are not
present in the body are introduced into the body to
treat the disease.
 Eg:
 L- Asparaginase in treatment of certain leukemia
 Leukemia requires L- asparagine for growth.
 L-Asparaginase administration removes L-
Asparaginase from blood resulting in regression of
the tumour.
 This enzyme is administered in an immobilized and
biodegradable form, viz., as polylactic acid capsules.

10. Industrial applications
 Pharmaceutical and food industries
 L-amioacids
 Chemical synthesis results in racemic mixtures ,L-
and D- forms. D- forms are not metabolized in the
body they are removed enzymatically by using
immobilized amino acid acyases(Japan)
 Soft drink industries
 High fructose corn syrup – sweetening agent
 Produced from glucose by the immobilized glucose
isomerase (Europe, Japan, USA)

11. Other immobilized enzymes in industries
Immobilized enzyme Substrate Product
Raffinase Raffinose in sugar beet
juice, soybean and milk
Raffinose free solutions
Glucomylase Dextrin produced by
α-amylase
D-Glucose
Invertase Sucrose Invert sugar(artificial
honey)
Lactase(in cellulose
triacetate fibres)
Milk and whey Lactose free milk(baby
foods)
Aspartate ammonia lyase Fumarate and Ammonia L-Aspartic cid

12. THANK YOU