Two NJIT "Rising Stars" are Named Senior Members of the National Academy of Inventors

Murat Guvendiren, a chemical and materials engineer who designs biomaterials that train stem cells to differentiate in the proper sequence to form functioning organs and tissues, and Mengyan Li, a microbiologist who develops sustainable water remediation techniques to biodegrade persistent industrial pollutants, have been named senior members of the National Academy of Inventors (NAI).

Guvendiren and Li are among 83 researchers from 41 NAI member institutions and research universities named to the class of 2022. Collectively, the new members are named on 1093 issued U.S. patents.

"Today, these Senior Members, on their path of prolific discovery, join the NAI innovation community," said Paul R. Sanberg FNAI, president of the NAI, in a news release. "With the NAI Senior Member award distinction, we recognize and honor these innovators who are rising stars in their fields."

In his Instructive Biomaterials and Additive Manufacturing Laboratory, Guvendiren is developing biomaterials that would enable the production of fully functional, human-scale tissues and organs to replace failed ones. A current focus is a treatment for osteoarthritis, the most common chronic musculoskeletal disorder of the joints. While joint replacements work well in older patients, they hold less promise for younger people, with failure in the long-term nearly guaranteed. His plan is to restore the damaged tissue itself.

“Optimally, we would produce tissues and organs from a person’s own medical images and cells to manufacture personalized materials that would not be rejected,” says Guvendiren, whose lab designs biodegradable polymers and hydrogels with tunable properties, develops material-based technologies to control stem cell differentiation, fabricates patient-specific in vitro disease models for fundamental studies and drug screening and engineers medical devices, tissues and organs using 3D-bioprinting.

To date, bioinks, hydrogels seeded with live human cells that are 3D-printed in the lab, cannot fully mimic the dynamic properties of native tissue, such as changes in stiffness and biochemistry. These properties take shape in the body’s extracellular matrix during tissue development, disease progression and the healing process. 

Guvendiren’s bioinks are “cell-instructive” materials that train stem cells to differentiate into different cell types in the right sequence to create a functional tissue. Their hydrogel casing, which is composed of a polysaccharide found in nature, including the body, functions as a supportive matrix for the cells that is “cured” into the desired structure with blue light. It degrades as it is replaced by naturally produced extracellular matrix.

Bioprinting the interface between cartilage and bone is difficult, because the tissues are so different: bone is hard, has a unique architecture and is threaded with blood vessels; cartilage is soft and has none. The cells that compose each must be created in a precise sequence.

“Our goal is to investigate the ability of our smart bioinks to create a cell-instructive material to regenerate bone with built-in vasculature that will gradually transition into cartilage using adult human mesenchymal stem cells, which is not possible with conventional fabrication techniques,” explains Guvendiren, whose work is backed by a National Science Foundation CAREER grant.

He currently holds three patents related to an earlier invention, an adhesive technology based on a protein found in marine mussels, that was licensed for use in biomimetic bioadhesives and sealants for soft tissue repair, orthopedics, sports medicine and spine and neurosurgery.

In his Environmental Microbiology and Biotechnology Laboratory, Li is matching hungry microbes with customized menus of industrial pollutants, from chemical solvents, to microplastics, to pharmaceuticals, to per- and polyfluoroalkyl substances, or PFAS. His goal is to create green, energy-efficient approaches toward remediating pervasive contaminants that resist both natural degradation and conventional cleanup techniques. 

“We identify strains of bacteria that are able to consume them, develop methods to accelerate their digestive powers and build devices such as biofilters and bioreactors to deploy in different settings,” says Li, who is assembling a collection of promising microbes harvested from wastewater treatment systems. 

He recently patented the use of a microbial strain called DD4 (Azoarcus sp.), which degrades 1,4-dioxane, an organic chemical stabilizer in products such as shampoos, laundry detergents and paints that is found at unsafe levels in groundwater and drinking water sites across the U.S. One of DD4’s enzymes, toluene monooxygenase, initiates decomposition of the compound’s stable circular structure so that it can be more easily degraded by other enzymes. To elicit that action, the microbe is first fed with chemicals such as propane or 1-propanol that prompt the enzyme’s expression.

What is especially encouraging about DD4 is that it also degrades another class of pollutants, chlorinated solvents, which often coincide with dioxane. Typically, they are treated separately, often using treatments such as oxidizing chemicals that can themselves be hazardous.

“The goal is to find microbes that degrade multiple contaminants, are active in diverse environments, including nutrient-limiting ones, and regenerate,” Li noted, adding that his lab is developing new approaches to accelerate the performance of key enzymes. 

“There are numerous environmental factors that affect a microbe’s performance if it is directly injected into places of contamination. However, water treatment facilities may be able to use add-on devices, such as bioreactors or biologically active filters, where water passes through the system and the bacteria inside consume the 1,4-dioxane so that the discharge is clean water,” said Li, a National Science Foundation CAREER award winner who holds three patents. Government agencies, including the Environmental Protection Agency, and environmental consulting firms collaborated with him on the application of this patent for field treatment.

"It is so exciting to watch our inspired and resolute young researchers forge new paths with their inventions,” said Atam Dhawan, NJIT's senior vice provost for research. “We are also enormously proud that they take on some of the most difficult problems in their fields. To address the dearth of organs and tissues for transplantation, Murat is helping to usher in a new era in tissue engineering by developing the next generation of 3D bioprinting. Mengyan is taking a sustainable approach to remediating some of the most persistent and treatment-resistant industrial chemicals.”