New Instruments Keep Center at Frontier of Aquatic Science

New Instruments Keep Center at Frontier of Aquatic Science

New instrumentation is opening up frontiers of research and educational opportunities at the Center for Aquatic Cytometry (CAC) at Bigelow Laboratory for Ocean Sciences. Advanced spectral cytometry equipment could help scientists differentiate plankton species and populations with more detail and precision than ever. A recent professional development course at the center provided an ideal opportunity to test out the new technology and highlighted how, paired with revamped educational spaces at Bigelow Laboratory, it will enable the study of microscopic organisms in new ways.

"These new instruments allow us to discern and understand - in far greater detail and much faster than before - the microscopic organisms at the base of the food web that are often indistinguishable with traditional analytical tools," said Senior Research Scientist Nicole Poulton, director of the CAC. "It's really going to push us on what's possible scientifically and what we can offer to other researchers and students interested in this valuable technology."

Supported by a philanthropic donor, CAC acquired a five-laser spectral flow cytometer from Agilent Technologies that Poulton describes as "cutting edge as it gets" - which is fitting, since CAC has been a pioneer of this technique since the institute's earliest days. In fact, Bigelow Laboratory's co-founder Clarice Yentsch was the first to adapt the advanced technique from the biomedical field to aquatic sciences.

Flow cytometry involves suspending particles, like cells, in a fluid and passing them single file in front of a laser beam. Each will light up at a different wavelength and intensity, based on unique characteristics like size and shape. Scientists can then group and sort particles that have similar fluorescence.

Traditionally, that required grouping things that emit light within the same broad band of wavelengths. With spectral flow cytometry, though, fluorescing molecules aren't described by a single wavelength but by a full spectrum of emitted light, giving each a unique signature.

The CAC does have a spectral flow cytometer, but it has only three lasers. The new one from Agilent has five, meaning it can pick up as many as 70 colors, which will help distinguish similar pigments and illuminate subtle differences. Poulton describes it like going from a handful of crayons to a super-sized pack - and being able to draw a more detailed, useful image as a result.

The recent acquisition of this state-of-the-art instrumentation was made possible by longtime supporters Craig and Kate Muir. Their gift is helping research groups and centers across Bigelow Laboratory build analytical capacity and stay at the forefront of different ocean science techniques.

"We know that engineering and technology that enable precise analytical measurements, which further the understanding of complex biological systems, is foundational to important research in ocean science, biomedicine, and agriculture," Craig Muir said. "It has been rewarding to see our long-standing relationship with Bigelow and Agilent help several groups strengthen their laboratory capabilities and advance key ocean science missions."

At the same time, the CAC is hoping to acquire a spectral cell sorter as part of a $2.7 million award from NSF's Major Research Instrumentation program to expand the capacity of the institute's single-cell genomics workflow, of which flow cytometry is a critical step.

Poulton hopes that the new spectral equipment will provide the detail necessary to begin distinguishing individual plankton species and populations that have historically been lumped together. Promising experiments run by Sea Change Semester student Isabelle Benson last fall, she says, showed that some populations of plankton collected off a local dock emitted a unique spectral signature. With spectral tools, then, scientists could theoretically measure those nuanced differences and sort and characterize plankton populations more granularly. That will open the door for new scientific applications and help researchers better understand how plankton communities are changing in different parts of the ocean.

The Introduction to Aquatic Flow Cytometry course that Poulton led this May provided a glimpse into how the equipment will also facilitate new educational opportunities for a variety of stakeholders.

The roughly biannual course is open to graduate students, postdocs, professional scientists, industry representatives - anyone, Poulton says, who has a question in mind, access to a flow cytometer, or interest in exploring novel applications of the technique. Over the course of several days, participants learn the basics of flow cytometry, cell sorting, and data analysis, with plenty of time geared toward their individual interests and needs.

With access to expanded educational facilities in the Alfond Center for Ocean Education and Innovation, Poulton was able to bring in and demo additional instruments from various vendors during this year's course. That enabled industry representatives and course participants to get more hands-on experience, providing a greater appreciation for the broad range of services the center offers.

"This is a rapidly evolving and exciting field, and this new equipment is helping us stay at the forefront," Poulton said. "These investments in innovation and education go hand-in-hand and are really expanding what we're able to do and offer at the center, which is going to benefit aquatic science around the world."