Guanine Inc. have announced a new technology for amplifying protein and microbe detection signals. The technology uses microbeads containing millions of oligonucleotides comprising electroactive guanine molecules along with a ligand to bind the microbeads with target analytes.

The massive number of guanine tags amplifies the detection signal so each individual analyte can be measured with a low cost electrochemical biosensor. The analytes are captured from a sample using magnetic bead purification to remove nonspecific materials that can interfere with detection. Analytes are sandwiched between magnetic microbeads and amplification microbeads, then guanine tags are eluted to hybridize with complementary cytosine probes on individual biosensor electrodes. A voltammetry scan oxidizes guanine and generates an electrical current proportional to the concentration of the analyte.

When the amplification system was applied to wastewater samples, the technology measured 3 cfu/mL of E. Coli O157:H7 among millions of heterotrophic bacteria, according to a study published in the Journal Sensors. “The technology is extremely flexible,” said Dr. Bruce Gale, Chief Science Officer of Guanine Inc and Professor at the University of Utah. “Our team was able to improve detection sensitivity by increasing the number of guanines per microbead. If bacteria are alive, we can use a second test to measure an increased detection signal in a fraction of the time of cell cultures.”

“Detecting pathogens at an early stage provides more treatment options and lower treatment costs,” said Neil Gordon, President of Guanine Inc. “Our technology changes the paradigm because for the first time ultra-low levels of proteins, microbes and nucleic acids can be quantified in the same test.” Guanine offers a service for developing rapid, simple and inexpensive tests that apply the technology.

For more information, see www.guanineinc.com