This document discusses biosensors for assessing food quality. Biosensors use living organisms to check various quality aspects of food, including nutritional components, additives, pesticides, heavy metals, and microbial content. They have advantages over traditional methods like chromatography in being selective, sensitive, reliable, fast, stable, simple, and low-cost. Biosensors detect analytes using biological sensing elements like enzymes, antibodies, and nucleic acids connected to transducers that detect changes in properties like light, frequency, mass, or temperature. They can check for heavy metals, herbicides, and pesticides and are useful for medical and food quality applications.

1. Biosensors for Food Quality
Assessment
Living organism to check quality of
food

2. Food Quality
• Safety
• Shelf life
• Consistency

3. Biosensors can check:
• Nutritional component
• Epidemiological research
• Nutritional fact
• Microbial Content

4. Biosensors can check:
• Food Additives
• Pesticides and herbicides
• Heavy Metals

5. Analyte
• The substance which we have to
analyze/check
• Analyte can be:
1. Liquid = Most easy to detect
2. Solid = harder to detect
3. Paste = Intermediate

6. Qualities of Good Biosensor
• High selectivity and sensitivity
• Reliability
• Short Assay time
• Stability
• Simplicity
• Low cost for operation and storage

7. Biological sensing elements used in
biosensors
• Enzymes
• Antibodies
• Nucleic acids
• Full bacterial cell
• Whole tissue
• Higher organisms

8. Transducer
• The detector which detect the change like the
change in light/ frequency etc
Qualities of Transducers:
1. Electrochemical
2. Optical
3. Mass change
4. Thermal change

9. Traditional method
• LC (Liquid chromatography)
• GC (gas chromatography)
• HPLC (high performance liquid
chromatography)

10. Other methods
1- Bioluminer Sensor
• Luciferase enzyme = light
2-Piezoelectric sensor (PZ)
• When analyte bind with biosensor, it cause
increase in size which in turn cause decrease
in oscillation
3- Antibody-based Biosensor:
• Mixture

11. Herbicide and pesticide detection
• We use chromatographic techniques
1- MRM (multi residue method)
• For wide range of pesticides
2- Selective MRMs:
• For closed range of pesticides

12. Chelating proteins
• Heavy metal sensors
• To check the heavy metals like copper,
cadmium, zinc and mercury
• 92% sold biosensors for medical purpose
• 6% biosensors used for food detection