For large-scale genomics research, Promega offers a workflow for isolating genomic DNA (gDNA) from large volumes of whole blood using its ReliaPrep™ HT gDNA isolation system integrated on Hamilton’s MicroLab® StarPlus liquid-handling workstation.
To avoid the inherent limitations of centrifugation-based methods for gDNA preparation—mainly the need to balance sample numbers and weights, and additional restrictions related to centrifuge capacity and operation—Promega developed ReliaPrep chemistry, explains Cristopher Cowan, manager, integrated solutions and engineering.
It requires no centrifugation step to remove red blood cells or other plasma components, allowing ReliaPrep to capture all of the nucleic acid in a whole-blood sample. Storage and transport of blood samples prior to processing may expose the samples to freeze/thaw cycles or other conditions that can compromise the sample, lysing white blood cells.
“You may have already lost much of your DNA yield before you even get to the precipitation step,” says Cowan. Rapid processing of 32 3–10 mL samples at a time takes place on the ReliaPrep’s HSM 32 LV device, which performs heating, shaking, and magnetization functions in one location. Automated liquid-level sensing allows the control software to scale the chemistry in each processing tube based on the volume of individual samples.
In a poster presentation at “LabAuto”, Promega illustrated the efficiency of DNA recovery on ReliaPrep compared to a precipitation-based method using 10 mL samples of both fresh blood and blood samples exposed to two freeze/thaw cycles. The results show improved yield and purity based on UV absorbance spectroscopy data measured after elution of the gDNA or resuspension of the DNA pellets.
According to Cowan, the ReliaPrep system uses a minimal amount of plasticware for gDNA isolation. Each blood sample is processed in a single 50 mL conical tube using two pipette tips—one for the elution and one for the removal of waste.
The Hamilton MicroLab StarPlus can integrate with three 32-sample ReliaPrep HSM devices. The Promega/Hamilton method can process 96 samples in less than 8 hours, with an average yield of about 300 µg of DNA per 10 mL of blood.
The concept of a benchtop robotic workstation designed to maximize the number and types of devices with which it can integrate, while maintaining a relatively compact perimeter to preserve workspace, was the central theme of a poster presented at “LabAuto” by Agilent Technologies.
Seeing a gap not only in its own product line—between the small-scale BenchCel Microplate Handler and the Direct Drive Robot (DDR)—but also in the broader market for robotic liquid-handling systems, Agilent envisioned an instrument that would be applicable across multiple workflows, including genomics and sample preparation for next-gen sequencing, cell-based assays, maintenance of cell stores, sample management for high-throughput applications, and ELISA-based assays.
Agilent’s BenchBot, introduced at “LabAuto” and set to begin shipment to customers this month, offers customers a midsize robotic system from which they can build a customized workstation and is sized to operate inside a standard fume hood. It can accommodate up to 10 devices at a time, has a vertical reach of 20–420 mm, a radial reach of 590 mm, a 270° work space, five degrees of freedom (z-axis, shoulder, elbow, wrist, and gripper), and an average pick-and-place transfer time of five seconds.
The goal, says Marc Valer, product manager, integrated systems, is to enable customers to “create larger workstations in a smaller footprint, encompassing a whole workflow with one system.”
The software includes a menu of operations for more than 140 different devices, allows for remote monitoring of robot status, and includes the One Touch Teaching function, with which users can manually place a plate at a desired position, press a button, and the software will record the information needed to instruct the robot to dispense at that position.
The Benchbot’s gripper can grasp microplates in either portrait or landscape orientation, and the robotic arm can access various types of labware housed in a plate hotel or plate stack storage device or a unit that enables random access.