The project entitled MICROCONTOLLER BASED ELISA READER is an 8 channel vertical light spectrophotometer designed to measure the absorbance of liquid in flat bottomed wells. The software enables complete control of this instrument parameters like wavelength selection, channel selection, blanking methods, data analysis and display. As there are 96 wells, the columns of the micro-plate are moved to required position by STEPPER MOTOR. Depending upon the required of the designer, the motor can be moved precisely to get required position which is done by interfacing stepper motor with microcontroller. The port pins of the microcontroller given to the driver IC whose output will be half step or full step rotations which will be driving the required stepper motor. The electronic part of the project in the system is interfacing the microcontroller with the stepper motor via driver 5804 IC. Well, this system is used to find out different types of viruses as well as the amount of proteins present in plant biology like stems, leaves etc and also in veterinary science quality of veterinary products. The detection of viruses will be based on the absorbance of samples which produces different colors to find out the concentration of required material.

1. MICRO CONTROLLER BASED
ELISA READER
By
P. Mahender Babu(10PQ1A0474)
G.Shyam Kumar(10PQ1A04A2)

2. OVERVIEW
• Objective
• Introduction
• Principle of Operation
• Description of the System
• Block Diagram
• Interfacing Stepper Motor with Microcontroller
• Elisa data from Three different patients
• Elisa Reader
• Applications of Elisa Reader
• Scope of Development

3. Introduction
Why known as ......ELISA?
ELISA is the abbreviation of Enzyme-Linked Immuno Sorbent
Assay
• Antigen of interest is absorbed on to plastic surface
(“sorbent”)
• Antigen is recognised by specific antibody (“immuno”)
• This antibody is recognised by second antibody (“immuno”)
which has enzyme attached (“enzyme- linked”)
• Substrate reacts with enzyme to produce product, usually
coloured.

4. ANTIGEN (Ag)
• Any molecule that induces
production of antibodies When
introduced in the body of an
animal is called antigen.
e.g. bacteria, viruses
ANTIBODY ( Ab)
• Proteins produced by the immune
system which help defend against
antigens.
e.g. lymphocytes
SYMBOL FOR ANTIBODY
SYMBOL FOR ANTIGEN

5. PRINCIPLE OF OPERATION
• It is based on the principle of Spectrophotometry
• A spectrophotometer is an instrument that measures the
amount of light absorbed by a sample.

7. DESCRIPTION OF THE SYSTEM
• Elisa Plate-Flat or bottomed 96 wells micro plate
• Light source: tungsten - halogen lamp
• Optical system: Grating Monochromator
• Optical Fibre
• MicroControllers-8051F124,ATMEL 89C52
• DRIVER IC 5804
• Detector: Photo diode
• Display: 24*2 line alphanumeric LCD
• Power supply: 230+-10% Ac, 50 Hz
• 2 Stepper Motors

8. Elisa Plate
•The equipment of ELISA consists of a micro-
plate which consists 96 wells. The wells are
arranged in the form of 8 rows and 12 columns.
By this arrangement we can detect 96 samples at
a time.
•Marked on one side alphabetically
•Numerically on the other side

9. Tungsten Lamp
This lamp consists of a tungsten filament enclosed in
a glass envelope, with a wavelength range of about
330 to 900 nm, are used for the visible region. It has
long life about 1200h.
Monochromator
Accepts polychromatic
input light from a lamp
and outputs
monochromatic light.

10. Optical Fibers
• Fibre optics (optical fibers) are long, thin
strands of very pure glass about the
diameter of a human hair. They are arranged
in bundles called optical cables and used to
transmit light signals over long distances.
It has the following parts:
• Core - Thin glass center of the fiber where
the light travels
• Cladding - Outer optical material
surrounding the core that reflects the light
back into the core
• Buffer coating - Plastic coating that protects
the fiber from damage and moisture

11. Micro Controller 8051F124
Thin Quad Flat Pack (TQFP)

12. MICROCONTROLLER C8051F124
Specifications:
• Core Processor: 8051
• Program Memory Size: l28k bytes of in-system programmable FLASH
memory
• RAM Size: 8448 (8k + 256) bytes of on-chip RAM
• Number of I /O: 64
• Package / Case: 100-TQFP
• Speed: 50MHz
• Oscillator Type: Internal
• Packaging: Tray
• Program Memory Type: FLASH ; EEPROM
• Data Converters: A/D 8x8b, 8x12b; D/A 2x12b
• Operating Temperature: -40°C ~ 85°C
• Connectivity: EBI/EMI, SMBus (2-Wire/I²C), SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, Temp Sensor, WDT
• Voltage - Supply (Vcc/Vdd): 2.7 V ~ 3.6 V

13. Microcontroller ATMEL AT89C52
• Compatible with MCS-5l Products
• 8k bytes of In-System Reprogrammable Flash Memory .
• Endurance: 1,000 Write/Erase Cycles
• Fully Static Operation: 0 Hz to 24 MHz
• Three-level Program Memory Lock.
• 256*8 -bit Internal RAM.
• 32 Programmable I/O Lines .
• Three 16-bit Timer/Counters .
• Eight Interrupt Sources .
• Programmable Serial Channel.
• Low-power Idle and Power-down Mode

14. DRIVER IC 5804
• 1.5 A Maximum Output Current
• 35 V Output Sustaining Voltage
• Wave-Drive, Two-Phase, and half-Step Drive Formats
• Internal Clamp Diodes
• Output Enable and Direction Control
• Power-ON Reset
• internal Thermal Shutdown Circuitry

15. Silicon PIN Photodiodes
Photovoltaic V-Series
• Designed for low-noise, D.C. to
medium bandwidth
applications. Active areas range
from .31mm² to 100mm².
Applications include: low light
level measurements, particle
counting, chemical and
analytical measurement and
detection.

17. Display: 24*2 line alphanumeric LCD

18. Elisa data from Three different
patients
Positive
Control
Patient A Patient B Patient C
1.689 0.055 0.412 1.999

19. ELISA READER
Instrumentation Division (E.C.I.L)

20. APPLICATIONS OF ELISA READER
• Screening donated blood for evidence of viral contamination by
– Presence of HIV antibodies in blood.
– Mycobacterial antibodies in tuberculosis.
• Screening of viral and bacterial Infections
• Detection of Hepatitis B markers in serum.
• Detection of rotavirus in faeces.
• Measuring hormone levels
– HCG (as a test for pregnancy)
– LH (determining the time of ovulation)
– TSH, T3 and T4 (for thyroid function)

21. SCOPE FOR DEVELOPMENT:
• Using proper interface devices it can be
controlled through a computer.
DISADVANTAGE:
• Requires spectrophotometric plate reader.

22. REFERENCES
• www.techno2know.com
• http://www.silabs.com/
• www.tecan.com
• www.maxima.in.com

23. Any Queries ?