150 likes | 335 Views
Waterborne Pathogen Prevention and Detection Using Traditional Methods and Microarray Probe Detection. Claribel Orellana CE 421 12/5/07. Biotechnology. Priorities: Agriculture and Medicine Malaria Vaccine Stem cell research Completion of the human genome map
E N D
Waterborne Pathogen Prevention and Detection Using Traditional Methods and Microarray Probe Detection Claribel Orellana CE 421 12/5/07
Biotechnology • Priorities: Agriculture and Medicine • Malaria Vaccine • Stem cell research • Completion of the human genome map • ‘Golden Rice’ modified to make vitamin A • GCSF for increasing white blood count in chemotherapy patients
World Concern: Water Quality • Half the world affected by contaminated water • Unsanitary conditions and lack of resources • Cause: waterborne pathogens
Waterborne Pathogens • Three different types: bacteria, viruses, and bacteria
Typical Contamination • Unprotected water source • Inadequate sanitation • Animal and fecal matter reaching water source • Surface runoff through the ground, water pipes and wells Well Cattle pond Well Surface drain Cattle pond
Typical Contamination • Animal and fecal matter reaching water source • Surface runoff through the ground, water pipes and wells
Traditional Practices for Safe Water • Point-of-use disinfection • Use of sodium and calcium hypochlorite • Safer and easier to use and distribute • Destroys most pathogens • Electrolysis • System run on solar power • Generators can generate enough disinfectant for 10,000 people. • Inexpensive
Traditional Practices for Safe Water • Safe Storage • Stored water vs. municipal tap • Container comparison • CDC container • Cantero
DNA Microarrays • DNA microarrays: reverse dot-blots for which sequence-specific “probes” are attached to substrate in a lattice pattern • spots are usually 100-200 micrometers and 200-500 micrometers away from each other and they represent specific probe sequences • Simultaneous detection vs. cultivation
Polymerase Chain Reaction (PRC) • PCR amplifies DNA sequences
Microarray Process • Sequences are hybridized • Specific bacterial targets are detected
Precision Factors • Assay sensitivity • Sample size • Efficiency of pathogen isolation • Efficiency of nucleic acid extraction • Effect of co-precipitating factors that inhibit PCR
Benefits and Limitations • Benefits: • Simultaneously detects pathogens • Not limited to identification by product length • Limitations: • Requires pathogens to be identified before configuring array • Needs to be validated • Currently more expensive than traditional methods
Application • EPA looking into feasibility • Is being monitored • Will most likely become a standard • Soon be more cost-effective • Priority is quick pathogenic detection