1. Detection of Harmful Algal Blooms (HAB) Created By: Matthew Barboza Supervising Professor: Dr. Sungyong Jung Analog Mixed signal Integrated Circuits (AMIC)

2. Purpose Main Problem: Harmful Algal Blooms (HAB’s) posing a threat to environment and local population. Current detection methods o Manual Sampling and Testing o accurate analysis – small areas, time consuming, after the event o Aerial Scanning o large area scan – uncertainties, may not be real-time Proposed Solution: Submerged array of sensors to provide real-time, large area identification for early warning and treatment

3. In Situ Wireless Sensing Network (WSN) Qualitative and quantitative analysis. Easy to cover vast space and time. Real time and in situ monitoring. Early warning system. Microsystin sensors

4. Overview Background: o Harmful Algal Blooms o Immunoassays o Optical Electronics, laser-diodes and PIN photodiodes o Transimpedance Amplifiers Set-up Devices Progress

5. Harmful Algal Blooms (HAB) What is a HAB? o Sudden increase of marine microorganism population algae, bacteria Why is it “harmful” o Hypoxic conditions (little oxygen) o Toxins e.g. Microcystin LR produced by Microsystis Aerugenosa

6. Immunoassay A technique of identifying a substance by its ability to bind to an antibody. - Collins English Dictionary

7. Laser Diodes Emission of light due to electron-hole recombination Monochromatic Narrow beam

8. Photodiode Incident light causes electron-hole pairs Carriers are swept across depletion region Increase in reverse current Current proportional to incident light PIN, P-type, Intrinsic, N-type

9. Transimpedance Amplifier (TIA) Input current signal Ii, output voltage signal Vo Amplifier gain is Vo/Ii (ohms)

10. Immunoassay Antibody – Antigen Bonding Site Laser Diode Photodetector Amplifier Circuit Microcontroller Analog to Digital Converter Wireless Transmitter Digitally Controlled Pulsing Communication Protocol Memory

11. Devices FDS1010 – Photodetector – Thorlabs D7805I – Laser Diode – Digikey OPA380 – Transimpedance amplifier – Digikey TiWi5 – Wireless dsPIC33FJ128MC802 – Microcontroller – Mouser

12. Progress Microcontroller Configuration o 25.3 ns Instruction cycle (98.8% of 40 MIPS) o 39525652 Timer Interrupt ( ~ 1 second) o Single, 10-bit, ADC conversion

13. K. G. Sellner et al., “Harmful Algal Blooms: Causes, Impact, and Detection” in Society for Industrial Microbiology, ‎ Copyright © 2003 EBSCO Publishing, DOI 10.1007/s10295-003-0074-9