Progress 09/01/20 to 08/31/21

Outputs
Target Audience:Currently our Target Audience remains our USDA Technical Monitor for this report, but we have also made inroads into two large integrated agrobiotech businesses that sell both dicamba and related herbicides as well as genetically engineered soybeans. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?This project has afforded significant business development training as well as scientific development for all of the scientists involved. How have the results been disseminated to communities of interest?Results thus far have only been disseminated under Confidentiality Agreements to our potential customers and development partners. What do you plan to do during the next reporting period to accomplish the goals?Summary of Phase II Effort: By the end of the Phase II effort, we will have established a novel platform for routine field testing of arbitrary water samples for dicamba. The test will have a sensitivity relevant to monitoring spray equipment for residual herbicide which could greatly injure sensitive non-engineered crops. We will also develop novel aptamers to at least three other herbicides including 2,4-D, glyphosate (RoundUp), and glufosinate. The development of these tests will follow what will become a well-established path to establishing sensitivity and specificity and familiarity of use for growers. To summarize, in order to meet the Phase II goals, Base Pair scientists, molecular biologists, engineers, and consultants will perform the following major tasks. Currently we are working through Goal #2 below and anticipate that the remaining goals will be quickly satisfied in the remaining year once we identify the most robust sensor chemistry. I. Base Pair personnel will finalize the design of an electrochemical aptasensor that is already performing with a sensitivity roughly 3000-fold better than needed to detect injurious levels. II. We will then characterize the limits-of-detection for two of the leading commercial formulations of dicamba to see if any adjuvant effects are observed. III. Base Pair personnel will also develop a dilution protocol that will be easy to perform by growers and applicators who will simply take a defined dropper volume of spray water and add it to a defined assay diluent (AD) buffer. IV. Base Pair molecular biologists will select additional aptamers for the sensor platform to 2,4-D, glyphosate, and glufosinate. V. In close collaboration with Biotex and Metrohm USA, we will develop a ruggedized version of Metrohm's DropSTAT reader with added Bluetooth and/or LTE communication capability for use with a customized cell phone app VI. Finally, working with our expert consultant, Mr. John Cobb we will place approximately 20 beta test units in the field with growers and spray applications for testing, feedback, and comparison of results with gold standard LC/MS measurements.

Impacts
What was accomplished under these goals? During the first year of this Phase II SBIR, we have made significant scientific progress in understanding the factors that enable a consistent/reproducible electrochemical measurement using aptamers on screen-printed electrodes and squarewave voltammetry. In several instances we have developed a single working dicamba sensor, however we are still observing differences between electrode responses, and we are working with our consultants and vendors to reduce inter-sensor variability. We are also establishing a formal relationship with a major semiconductor manufacturer with an interest in partnering or investing in this sensor product and others.

Publications