A High-Dimensional Space-filling DOE for Assay Development

SPT Labtech is a leading provider of lab automation solutions, specializing in the development of innovative technologies to streamline laboratory workflows. The company focuses on creating efficient and robust solutions to enhance the productivity and accuracy of scientific research. SPT Labtech's products are designed to address the challenges faced by pharmaceutical and life sciences industries, particularly in the areas of assay development and high-throughput screening. By leveraging advanced automation and data management tools, SPT Labtech aims to reduce the time and resources required for complex experimental processes, enabling researchers to achieve faster and more reliable results.

Pharmaceutical assay development groups work under constant time pressure and face increasing complexity without a commensurate increase in resources. As a result, these groups often adopt powerful statistical approaches such as DOE to shorten assay development cycles. DOE investigations enable the rapid optimization of many inputs and parameters simultaneously, offering the ability to quickly and easily execute and analyze higher-granularity, multifactorial characterizations of biological processes. Yet conventional DOE campaigns executed by hand still require weeks of iterative cycles, as the number of runs possible per cycle is limited by the need to minimize the complexity of manual calculation, liquid handling, and data collection tasks to avoid human error. The challenge for assay development is to increase the speed and accuracy of DoE campaigns by reducing time spent on planning, data aggregation, protocol execution, and liquid handling.

SPT Labtech combined dragonfly® discovery dispenser capabilities with Synthace experiment platform to increase speed, accuracy, and flexibility to execute a 6-factor space-filling DOE. Synthace experiment platform allows users to rapidly prototype complex automated liquid handling workflows by providing modules that can be easily rearranged and customized. Synthace could rapidly and flexibly generate an automated liquid handling protocol from the input DOE design file to send instructions to execute that campaign on the dragonfly® discovery, reducing the need for physical dry-runs to validate the protocol. The dragonfly® discovery allows teams to develop their assays using the same dispenser and high-density plates (384 or 1,536-well) as would be used in subsequent high-throughput workflows. Synthace automatically generates a detailed, digital record of every liquid handling and data aggregation step in that process, which significantly reduces risk of assays failing when transferring protocols into HTS. The 6-factor space-filling DOE required 3,456 runs in total for two sets of triplicates of 384 runs and the corresponding blanks. This amounts to 20,745 liquid handling steps, 2,305 for each of nine 384-well plates. Synthace guides users on required reagents, volumes, and labware with detailed schematics of how to set up the liquid dispenser and reagent reservoirs, and when to swap out the dispensing heads. The in silico simulation allows the user to validate the experimental workflow prior to physical execution. All low-level decisions are taken care of by Synthace so that the user isn’t required to manually determine plate maps and reservoir set-up before conducting a physical run in the lab, thereby reducing risk of human error or the need for repetitive dry-run physical testing in the lab before executing with valuable reagents. Synthace prompts the user to change the reservoirs when necessary, allowing more than 10 liquids to be layered onto the experiment plate. In the last step of the simulation, the user can select any well to inspect all the details of the liquids added during the protocol.

• The combination of SPT Labtech’s dragonfly® discovery dispenser with Synthace allowed for the characterization of a spectrophotometric enzymatic assay using a space-filling DoE with a total of 3,456 runs for three sets of triplicates of 384 runs and the corresponding controls.
• Synthace and dragonfly® discovery combine to create an efficient and robust solution to reduce assay development cycles with automated DOE execution and data aggregation.
• This approach can prevent future bottlenecks in assay transfer by enabling digitization of assay protocols and use of the same liquid handler from assay development through to high-throughput screening, reducing the need to miniaturize or re-optimize assays when proceeding into HTS campaigns.

• Synthace reduced time spent on planning the 20,745 liquid handling steps and data aggregation from the microplate reader by 75% and 94% respectively.
• The dragonfly® discovery reduced liquid handling time by 98% compared with an average pipetting robot.
• Eliminated 99.9% of the number of tips needed.