WashU-designed artificial antibodies on gold nanocages may lead to speedier detection of kidney injury

The incidence of acute kidney injury that requires dialysis has been on the rise in the United States since 2000, and the number of deaths from the disease more than doubled between 2000-2009. A team of researchers at Washington University in St. Louis is working to develop a technique using gold nanoparticles that will allow for faster screening, early detection, diagnosis and prognosis of the disease.

nanocages, Singamaneni, kidney injury
Singamaneni and his team are designing biosensors based on gold nanocages and artificial antibodies to detect certain proteins in urine and blood plasma.

Srikanth Singamaneni, PhD, associate professor of materials science in the School of Engineering & Applied Science, has received a two-year, $411,246 grant from the National Institute of Diabetes and Digestive and Kidney Diseases of the National Institutes of Health to design and produce biosensors based on gold nanocages and artificial antibodies to detect certain proteins in urine and blood plasma. The rapid, point-of-care method could be used in intensive care units or emergency rooms to quickly detect acute kidney injury, a sudden deterioration in kidney function, and lead to earlier diagnosis and treatment. Current detection methods require expensive tests that must be done in hospital-based labs and are not ideal for settings with limited resources.

"Gold nanocages are a new class of hollow metal nanostructures that provide significantly higher sensitivity compared to conventional plasmonic nanostructures, such as nanospheres or nanorods, making them better candidates for label-free detection of protein biomarkers in bodily fluids," Singamaneni says.

The gold nanocages with artificial antibodies would be designed to detect three protein biomarkers that have been considered for early diagnosis and prognosis of acute kidney injury: neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule 1 (KIM-1) and fatty acid binding protein 1 (FABP1).

Singamaneni has been working for several years with Evan Kharasch, MD, PhD, the Russell & Mary Shelden Professor of Anesthesiology and professor of biochemistry and molecular biology, and Jeremiah Morrissey, PhD, professor of anesthesiology, at the School of Medicine to develop a paper-based detection system using gold nanoparticles. With the support from the NIH, the team will design, create and test molecularly imprinted gold nanocages to NGAL, KIM-1 and FABP1 that have been identified as potential protein biomarkers for acute kidney injury. The artificial antibodies have no need for special storage and will reduce the cost of expensive lab testing, Singamaneni says.

Once the research is complete, the stage would be set for the next step, which is developing plasmonic, paper-based biochips for monitoring multiple biomarkers from urine, which enhances the accuracy of diagnosis and prognosis of various conditions, Singamaneni says.

The School of Engineering & Applied Science at Washington University in St. Louis focuses intellectual efforts through a new convergence paradigm and builds on strengths, particularly as applied to medicine and health, energy and environment, entrepreneurship and security. With 88 tenured/tenure-track and 40 additional full-time faculty, 1,300 undergraduate students, more than 900 graduate students and more than 23,000 alumni, we are working to leverage our partnerships with academic and industry partners — across disciplines and across the world — to contribute to solving the greatest global challenges of the 21st century.