Project Grant R44ES036049

MULTIPLEXED NUCLEAR RECEPTOR BIOASSAY PLATFORM TO INEXPENSIVELY AND BROADLY SURVEY THE NATION'S WATER SUPPLY FOR CONTAMINATION BY ENDOCRINE DISRUPTING CHEMICALS - CURRENT EPA GUIDELINES CALL FOR ROUTINE MONITORING OF DRINKING WATER FOR 59 CHEMICAL CONTAMINANTS, BUT 350,000 INDUSTRIAL CHEMICALS ARE MANUFACTURED THAT MAY CONTAMINATE WATER AND IMPACT HEALTH. WATER AUTHORITIES ARE EXPLORING FUNCTIONS-BASED BIOASSAY MEASUREMENTS TO CLOSE THAT GAP BETWEEN THE CURRENT AND DESIRED SCOPE OF MONITORED CHEMICALS. CHEMICALLY AGNOSTIC BIOASSAYS CAN DETECT ANY KNOWN OR UNKNOWN CHEMICALS IN A WATER SAMPLE THAT ALTER THE ACTIVITY OF A PROTEIN SENSOR, BUT WIDESPREAD IMPLEMENTATION HAS BEEN STALLED BY COST, PRECISION AND ACCURACY HURDLES. XCELLASSAY SOLVED THOSE HURDLES IN PHASE I. PHASE II WILL EXPAND THOSE ADVANCES TO A FULL SET OF BIOASSAYS SPECIFIED BY ITS PROSPECTIVE LEAD CUSTOMERS, WHICH ARE WATER DISTRICTS IN THE STATE OF CALIFORNIA. THAT LEAD PROVIDES AN EXCELLENT LAUNCHING PAD FOR NATIONAL AND GLOBAL EXPANSION. TODAY, THE LEAD CUSTOMERS PAY >$350 PER SAMPLE FOR ONE BIOASSAY MEASUREMENT. SINCE EACH WATER SAMPLE MUST BE SCREENED AGAINST MANY BIOASSAYS, THE MULTIPLYING OF THAT COST BECOMES UNTENABLE. XCELLASSAY'S MAJOR INNOVATION WAS TO CREATE MULTIPLEXED BIOASSAYS THAT SIMULTANEOUSLY MONITOR A WATER SAMPLE'S EFFECT ON MANY 'BAR-CODED' BIOASSAYS CO-PLATED INTO HIGH THROUGHPUT-COMPATIBLE 384-WELL DISHES. PHASE I ALSO DEMONSTRATED THAT THE SENSITIVITY, PRECISION AND ACCURACY OF XCELLASSAY'S MULTIPLEXED BIOASSAYS EXCEEDED THOSE OF COMPETITOR, NON-MULTIPLEXED BIOASSAYS. BEYOND SHOWING A VIABLE PATH FOR SYSTEM-WIDE EXPANSION OF AFFORDABLE BIOASSAY MONITORING, PHASE I DEMONSTRATED THE URGENT NEED FOR THOSE MEASUREMENTS: ACCURATELY QUANTIFIED CONTAMINATIONS ABOVE TOXICOLOGIC THRESHOLDS WERE FOUND IN SOME SAMPLES BOTH FROM MUNICIPAL WATER DISTRICTS AND PRIVATE TAPS. FOR PHASE II, THE LEAD CUSTOMER HAS REQUESTED THAT WE: AIM 1: REFINE AND FINALIZE WATER-PROCESSING PROTOCOLS THAT, IN PHASE I, REDUCED THE CUSTOMER'S CURRENT 2- DAY PROTOCOL REQUIRING 2 L OF A WATER SAMPLE TO A 10-MINUTE PROTOCOL USING "MAILABLE" 2 ML WATER SAMPLES. AIM 2: CREATE, CHARACTERIZE AND VALIDATE A SET OF 13 MULTIPLEXED BIOASSAY CELL LINES THAT INCLUDE BOTH SENSORS FOR BROAD CLASSES OF CHEMICALS AND SENSORS FOR SPECIFIC HIGH PRIORITY CLASSES OF CHEMICALS. THE PHASE II TECHNICAL AIMS DIRECTLY ALIGN WITH THE STRONG DESIRE BY GLOBAL AUTHORITIES FOR PAN-CHEMICAL, WATER MONITORING METHODS. WHILE BIOASSAY METHODS ARE BEGINNING TO BE USED AT HIGH-RISK SITES, BROAD ADOPTION THROUGHOUT WATER DISTRIBUTION NETWORKS REQUIRES SOLUTIONS THAT ARE AFFORDABLE, ACCESSIBLE, AND EASY TO USE. XCELLASSAY'S LOW-COST, "MAIL-IN" SAMPLE METHODS ALSO WILL EXTEND ACCESS TO ADVANCED WATER MONITORING TO INSTITUTIONAL AND AT-HOME CUSTOMERS CONCERNED ABOUT THEIR WATER QUALITY. BY MAKING PRODUCTS AFFORDABLE TO BOTH PUBLIC AND PRIVATE CUSTOMERS, XCELLASSAY WILL DEMOCRATIZE WATER MONITORING. LOOKING AHEAD, THE EXPANDED COLLECTION OF MEASUREMENT DATA WILL ENABLE GEOGRAPHIC AND TEMPORAL MAPPING OF CONTAMINATION FROM "STREAM TO TAP". SYSTEM-WIDE MONITORING WILL ALLOW RAPID IDENTIFICATION OF CONTAMINATION CLUSTERS (FOUND EVEN IN PHASE I) WHICH WILL HAVE BROAD SOCIAL IMPACT BY REVEALING HIDDEN VULNERABILITIES WITHIN THE WATER DISTRIBUTION GRID.