Detecting early-stage Lyme

DOUGLAS FARMER, SENIOR EDITOR doug.farmer@photonics.com

Lyme disease continues to infect a large swath of the population in North America. The reliance on the standard two-tiered serodiagnostic test to identify its presence has proved problematic because the bacteria that cause the disease — Borrelia burgdorferi — can be difficult to trace in the early stages. Some in the biomedical community are pinning their hopes for reliable testing on the photonics technologies found in chip-based assays and used to measure effects such as fluorescence and absorption.

The Tick-Borne Disease Working Group has placed this pursuit of reliable testing in a national context with its recent report to the U.S. Congress. The group estimates that tick-borne diseases in general — and Lyme in particular — are vastly underestimated in national statistics, and that incidences are potentially 8 to 12× higher than officially diagnosed. The need for reliable point-of-care diagnostic testing will only grow as the true infection rate comes into focus.

As I discuss in my cover story in this edition of BioPhotonics, researchers at institutions across the country are busy looking for light-based effects that can be produced when proteins in Lyme bacteria are present. The scientists are using gold nanoparticles to measure a colorimetric response — plasmonic fluorescence — and also the corresponding absorption. Others are utilizing microfluidics to identify the bacteria in the early stages of the disease. While commercialization of these concepts may be a few years away, studies involving a broad segment of the population are proceeding. Learn more here.

Another new technology for detecting and diagnosing conditions in the body is the subject of a feature by Jianglai Wu, Na Ji, and Kevin Tsia. These researchers developed a technique called free-space angular-chirp-enhanced delay (FACED), which generates a series of receding virtual images that can capture high-speed cellular processes via a module that can be attached to any standard microscope. Read more about this development here.

Elsewhere in this edition, Adam Glaser and Melissa Haahr write about a team of researchers that is using a form of light sheet microscopy to overcome the historical limitations of pathological analysis. The group has created open-top light-sheet microscopes, which place optical components below the specimen, allowing for the illumination of samples of varying sizes. Explore their efforts here.

Meanwhile, Sulayman Oladepo expounds on the invention of a smart probe that is based on a string of nucleic acids. The probe absorbs fluorescent dyes, revealing a variety of biomarkers, including those intrinsic to cancer. The probe is used to analyze micro-RNA that is linked to a cancer biomarker. Follow Oladepo’s research journey, which begins here.

And in “Biopinion,” the Forever Healthy Foundation discusses the benefits of low-level light therapy, a form of photobiomodulation. The foundation’s analysis verifies that light in the red and infrared regions can stimulate the skin and create a more youthful appearance. Read more about this topic here.

Enjoy the issue!