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Center for Advanced Regenerative Engineering

Unlocking our Body's Potential to Heal

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Ameer Wins 2022 Bioactive Materials Lifetime Achievement Award

Northwestern Engineering’s Guillermo A. Ameer has been named the 2022 Bioactive Materials Lifetime Achievement Award winner by the Bioactive Materials academic journal.

Established in 2021, the annual Bioactive Materials Lifetime Achievement Award recognizes excellence in research and development in the field of bioactive materials. The award is presented to a person judged to have demonstrated excellence and leadership in bioactive materials, including basic science and translation to practice. 

Ameer, Daniel Hale Williams Professor of Biomedical Engineering at the McCormick School of Engineering and professor of surgery at the Feinberg School of Medicine, is a leader in regenerative engineering, biomaterials, additive manufacturing for biomedical devices, controlled drug delivery, and bio/nanotechnology for therapeutics and diagnostics. His laboratory has pioneered the development of tissue regeneration applications of citrate-based biomaterials, the core technology behind the innovative bioresorbable orthopedic tissue fixation devices CITREFIXTM, CITRESPLINETM, and CITRELOCKTM, which were recently cleared by the FDA for clinical use and marketed worldwide by Stryker Corporation.

Read the full article in Engineering News

Ameer Elected to National Academy of Medicine


Northwestern Engineering's Guillermo A. Ameer was one of three University faculty elected to the National Academy of Medicine (NAM).   Election to the Academy is considered one of the highest honors in the fields of health and medicine, and Professor Guillermo Ameer’s laboratory is widely recognized for pioneering regenerative biomaterials based on a novel class of biodegradable polymers containing citrate, and using them to regenerate a variety of tissues and organs.

Ameer is the Daniel Hale Williams Professor of Biomedical Engineering in the McCormick School of Engineering and a professor of surgery in Northwestern’s Feinberg School of Medicine, and also the founding director of Northwestern’s Center for Advanced Regenerative Engineering. He is director of the recently established Regenerative Engineering Training Program at the McCormick School of Engineering, supported by the National Institutes of Health.

Read the full article in Engineering News.

Biomaterial pioneered in CARE available for use in musculoskeletal surgeries

September 24, 2021

Citregen reabsorption. Photo credit: Acuitive Technologies
Citregen reabsorption. Photo credit: Acuitive Technologies



Biomaterial developed in CARE labs to be widely available through a device by Stryker Corporation

The novel biomaterial Citregen™, developed in the Center for Advanced Regenerative Engineering, is being adopted into a new orthopaedic device being distributed by Stryker.  Stryker is one of the world’s leading medical technology companies, and their Trauma & Extremities division has launched its Citrelock™ Tendon Fixation Device System.  Citregen’s unique chemical and mechanical properties make this system an innovative offering in a number of ways.  For example, it provides a controlled and homogeneous resorption process that prevents bulk degradation and chronic inflammation, and maintains structural integrity during the healing phase, while the implant is replaced by host tissue.

Citrelock will be featured during one of Stryker’s industry sessions at AOFAS on Sept. 24. The company is also hosting a new product reception highlighting the benefits of Citrelock along with other recent additions to its Foot & Ankle portfolio. 

Read Stryker’s press release, find more information about Stryker’s product release here.

The development and commercialization of a novel biomaterial is a rare accomplishment.  Read an article in Northwestern Now by Lila Reynolds that features the development of CITREGEN™ in Dr. Ameer's labs.

Watch Stryker's video to learn more about Citrelock technology:


Medical devices that use biomaterial technology developed at CARE receive FDA clearance

March 4, 2021



Acuitive Technologies, Inc.  announced on March 4, 2021, U.S. Food and Drug Administration (FDA) approval of a third device designed using the core material technology CITREGEN, pioneered by Dr. Guillermo Ameer and his lab.

The CITRESPLINE/CITRELOCK™ system is intended to firmly engage tendons and ligaments within a bone tunnel while preserving the integrity of the soft tissue during insertion of the device. These products are intended to be used during orthopedic surgeries for fixation of ligament or tendon tissue repairs of the knee, shoulder, elbow, wrist, hand, ankle, and foot.  Acuitivie Technologies, Inc. intends to commercialize the CITRESPLINE and CITRELOCK System with an orthopedic distribution partner to compete in the Sports Medicine market. 

Read the full press release by Acuitive Technologies, Inc. here.

Learn more about CITREGEN™ technology.


February 15, 2021

CITREFIX™ Knotless Suture Anchor System

Above: CITREFIX™ Knotless Suture Anchor System

On February 11, 2021, Acuitive Technologies announced a second product that uses CITREGEN™ material technology has also received FDA clearance.  The CITREFIX™ Knotless Suture Anchor System is intended to assist the attachment of tissue to bone during orthopedic surgeries such as fixation of ligaments or tendon graft tissue repairs of the shoulder, elbow, wrist, hand, knee, ankle, and foot extremities.  Read more about the product and announcement here.


CITRELOCK tendon fixation devices. Credit: Acuitive Technologies

Above: CITRELOCK tendon fixation devices. Credit: Acuitive Technologies

The Center for Advanced Regenerative Engineering, led by its director  Guillermo Ameer, has pioneered an innovative orthopedic medical device fabricated from a novel biomaterial, and has received clearance from the U.S. Food and Drug Administration (FDA) for use in surgeries to attach soft tissue grafts to bone.
The biomaterial is the first thermoset biodegradable synthetic polymer ever approved for use in an implantable medical device.  Ameer’s biomaterial, called CITREGEN™, helps grafted tissues heal by recreating their intrinsic biochemical and structural support network.  CITREGEN™ is the core material technology in the CITRELOCK™ Interference Screw System, which will be produced and marketed by Acuitive Technologies, Inc. The system is intended for soft tissue attachment or fixing ligaments and tendon graft tissue in joint surgeries.  “CITREGEN is an unprecedented and innovative bioresorbable biomaterial technology developed to support the body’s normal healing process and promote tissue regeneration,” Ameer said. “When used to fabricate devices for reconstruction of tissues, such as ligaments, blood vessels, bladder and bone, results have been impressive and beyond our expectations.”

Read the full story about the device as covered by Northwestern News.

 The CITRELOCK Interference Screw System will become available through Acuitive’s orthopaedic distribution partner in early 2021.  Read more about Acuitive's FDA Clearance in this release.


What is CARE

Housed within the McCormick School of Engineering and Applied Science, the Center for Advanced Regenerative Engineering (CARE) is a targeted initiative led by Prof. Guillermo Ameer that integrates and supports research, technology development, and clinical expertise to improve the outcome of tissue and organ repair and regeneration for adult and pediatric patients. CARE is a partnership that includes Northwestern University's Feinberg School of Medicine, the University of Chicago's Pritzker School of Medicine, the Shirley Ryan AbilityLab, the Ann and Robert H. Lurie Children’s Hospital of Chicago, the International Institute for Nanotechnology, and various companies interested in the implementation of regenerative medicine.

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