Houston-based Circulus, which just received a $100 million credit facility, focuses on innovative plastics recycling. Photo via circulus.com

Fueled by a new $100 million credit facility, a Houston-based company that specializes in plastics recycling is establishing a nationwide network of recycling plants.

Circulus Holdings secured the $100 million credit facility from Riverstone Credit Partners, which has an office in Houston. This "green" loan is aimed at supporting environmental sustainability.

David Hudson, founder and CEO of Circulus, says in a news release that the credit facility "enables Circulus to rapidly develop a broad network of facilities and further the company's commitment to sustainable manufacturing. We look forward to supporting green-based jobs and preserving our environment for future generations."

Circulus, a portfolio company of Houston-based private equity firm Ara Partners, recently opened its first plastics recycling facility. The 110,000-square-foot plant is in Riverbank, California, near Modesto. It employs 45 people. So far, other Circulus plants, each of which will be larger than the California facility, are planned for Alabama, Oklahoma, the Midwest, and the Northeast.

Circulus is building plants that will transform lower-grade plastic into post-consumer resin so that it's suitable for commercial and industrial uses.

Circulus says it is diverting plastic from landfills, incinerators, and oceans and "upcycling" it into products, including plastic bags and plastic wrap. Customers for those products include retailers, resin producers, packaging manufacturers, and makers of consumer packaged goods. The company says greenhouse gas emissions associated with production of its post-consumer resin are about 88 percent below that of virgin resin.

"Through our significant investment in infrastructure and commitment to manufacturing excellence, we are supporting green job creation and reinforcing the nation's global position in sustainable manufacturing," Hudson says in a news release.

Before Circulus, Hudson was an operating partner at Ara Partners.

Founded in 2019, Circulus employs a dozen people in Houston and plans to add workers here as its network of facilities expands. Circulus is set up as a public benefit LLC, a for-profit business that promotes a social benefit for the public.

Ara Partners invests in decarbonization-focused businesses in the manufacturing, chemicals and materials, energy, and food and agriculture sectors. Aside from Circulus, portfolio companies include Houston-based Path Environmental Technology, which provides a decarbonization-oriented industrial services platform for above-ground storage tanks, and Arlington-based Priority Power Management, an energy services provider whose priorities include carbon neutrality and smart energy.

Circulus is breaking into a plastics recycling market whose global size in 2020 was estimated at $39.9 billion, according to Imarc Group, a market research company. The firm projects the market will grow to $56.5 billion by 2026.

"The demand for plastic material has been constantly increasing across several industries like food and beverage, automotive, packaging, and healthcare. The development of these industries can be accredited to rising population, inflating disposable incomes, and continuous product innovations," Imarc Group says. "In this context, higher manufacturing cost of virgin resins has necessitated the use of recycled plastic products, thereby bolstering the growth of the global recycled plastics market."

Verified Market Research estimates the global market for post-consumer recycled plastics at nearly $15.2 billion in 2020 and forecasts it will rise to almost $22.4 billion by 2028.

"The products produced from these plastics close the loop by diverting them from landfills and enabling them to be recycled," Verified Market Research says. "The advantages of employing post-consumer plastics also assist in addressing … microplastics in the environment. Microplastics are originated from plastic waste that has been deposited into the environment."

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New Houston biotech co. developing capsules for hard-to-treat tumors

biotech breakthroughs

Houston company Sentinel BioTherapeutics has made promising headway in cancer immunotherapy for patients who don’t respond positively to more traditional treatments. New biotech venture creation studio RBL LLC (pronounced “rebel”) recently debuted the company at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago.

Rima Chakrabarti is a neurologist by training. Though she says she’s “passionate about treating the brain,” her greatest fervor currently lies in leading Sentinel as its CEO. Sentinel is RBL’s first clinical venture, and Chakrabarti also serves as cofounder and managing partner of the venture studio.

The team sees an opportunity to use cytokine interleukin-2 (IL-2) capsules to fight many solid tumors for which immunotherapy hasn't been effective in the past. “We plan to develop a pipeline of drugs that way,” Chakrabarti says.

This may all sound brand-new, but Sentinel’s research goes back years to the work of Omid Veiseh, director of the Rice Biotechnology Launch Pad (RBLP). Through another, now-defunct company called Avenge Bio, Veiseh and Paul Wotton — also with RBLP and now RBL’s CEO and chairman of Sentinel — invested close to $45 million in capital toward their promising discovery.

From preclinical data on studies in mice, Avenge was able to manufacture its platform focused on ovarian cancer treatments and test it on 14 human patients. “That's essentially opened the door to understanding the clinical efficacy of this drug as well as it's brought this to the attention of the FDA, such that now we're able to continue that conversation,” says Chakrabarti. She emphasizes the point that Avenge’s demise was not due to the science, but to the company's unsuccessful outsourcing to a Massachusetts management team.

“They hadn't analyzed a lot of the data that we got access to upon the acquisition,” explains Chakrabarti. “When we analyzed the data, we saw this dose-dependent immune activation, very specific upregulation of checkpoints on T cells. We came to understand how effective this agent could be as an immune priming agent in a way that Avenge Bio hadn't been developing this drug.”

Chakrabarti says that Sentinel’s phase II trials are coming soon. They’ll continue their previous work with ovarian cancer, but Chakrabarti says that she also believes that the IL-2 capsules will be effective in the treatment of endometrial cancer. There’s also potential for people with other cancers located in the peritoneal cavity, such as colorectal cancer, gastrointestinal cancer and even primary peritoneal carcinomatosis.

“We're delivering these capsules into the peritoneal cavity and seeing both the safety as well as the immune activation,” Chakrabarti says. “We're seeing that up-regulation of the checkpoint that I mentioned. We're seeing a strong safety signal. This drug was very well-tolerated by patients where IL-2 has always had a challenge in being a well-tolerated drug.”

When phase II will take place is up to the success of Sentinel’s fundraising push. What we do know is that it will be led by Amir Jazaeri at MD Anderson Cancer Center. Part of the goal this summer is also to create an automated cell manufacturing process and prove that Sentinel can store its product long-term.

“This isn’t just another cell therapy,” Chakrabarti says.

"Sentinel's cytokine factory platform is the breakthrough technology that we believe has the potential to define the next era of cancer treatment," adds Wotton.

How Houston's innovation sector fared in 2025 Texas legislative session

That's a Wrap

The Greater Houston Partnership is touting a number of victories during the recently concluded Texas legislative session that will or could benefit the Houston area. They range from billions of dollars for dementia research to millions of dollars for energy projects.

“These wins were only possible through deep collaboration, among our coalition partners, elected officials, business and community leaders, and the engaged members of the Partnership,” according to a partnership blog post. “Together, we’ve demonstrated how a united voice for Houston helps drive results that benefit all Texans.”

In terms of business innovation, legislators carved out $715 million for nuclear, semiconductor, and other economic development projects, and a potential $1 billion pool of tax incentives through 2029 to support research-and-development projects. The partnership said these investments “position Houston and Texas for long-term growth.”

Dementia institute

One of the biggest legislative wins cited by the Greater Houston Partnership was passage of legislation sponsored by Sen. Joan Huffman, a Houston Republican, to provide $3 billion in funding over 10 years for the Dementia Prevention and Research Institute of Texas. Voters will be asked in November to vote on a ballot initiative that would set aside $3 billion for the new institute.

The dementia institute would be structured much like the Cancer Prevention and Research Institute of Texas (CPRIT), a state agency that provides funding for cancer research in the Lone Star State. Since its founding in 2008, CPRIT has awarded nearly $3.9 billion in research grants.

“By establishing the Dementia Prevention and Research Institute of Texas, we are positioning our state to lead the charge against one of the most devastating health challenges of our time,” Huffman said. “With $3 billion in funding over the next decade, we will drive critical research, develop new strategies for prevention and treatment, and support our healthcare community. Now, it’s up to voters to ensure this initiative moves forward.”

More than 500,000 Texans suffer from some form of dementia, including Alzheimer’s disease, according to Lt. Gov. Dan Patrick.

“With a steadfast commitment, Texas has the potential to become a world leader in combating [dementia] through the search for effective treatments and, ultimately, a cure,” Patrick said.

Funding for education

In the K-12 sector, lawmakers earmarked an extra $195 million for Houston ISD, $126.7 million for Cypress-Fairbanks ISD, $103.1 million for Katy ISD, $80.6 million for Fort Bend ISD, and $61 million for Aldine ISD, the partnership said.

In higher education, legislators allocated:

     
  • $1.17 billion for the University of Houston College of Medicine, University of Texas Health Science Center at Houston, UT MD Anderson Cancer Center, and Baylor College of Medicine
  • $922 million for the University of Houston System
  • $167 million for Texas Southern University
  • $10 million for the Center for Biotechnology at San Jacinto College.

Infrastructure

In the infrastructure arena, state lawmakers:

     
  • Approved $265 million for Houston-area water and flood mitigation projects, including $100 million for the Lynchburg Pump Station
  • Created the Lake Houston Dredging and Maintenance District
  • Established a fund for the Gulf Coast Protection District to supply $550 million for projects to make the coastline and ship channel more resilient

"Nuclear power renaissance"

House Bill 14 (HB 14) aims to lead a “nuclear power renaissance in the United States,” according to Texas Gov. Greg Abbott’s office. HB 14 establishes the Texas Advanced Nuclear Energy Office, and allocates $350 million for nuclear development and deployment. Two nuclear power plants currently operate in Texas, generating 10 percent of the energy that feeds the Electric Reliability Council Texas (ERCOT) power grid.

“This initiative will also strengthen Texas’ nuclear manufacturing capacity, rebuild a domestic fuel cycle supply chain, and train the future nuclear workforce,” Abbott said in a news release earlier this year.

One of the beneficiaries of Texas’ nuclear push could be Washington, D.C.-based Last Energy, which plans to build 30 micro-nuclear reactors near Abilene to serve power-gobbling data centers across the state. Houston-based Pelican Energy Partners also might be able to take advantage of the legislation after raising a $450 million fund to invest in companies that supply nuclear energy services and equipment.

Reed Clay, president of the Texas Nuclear Alliance, called this legislation “the most important nuclear development program of any state.”

“It is a giant leap forward for Texas and the United States, whose nuclear program was all but dead for decades,” said Clay. “With the passage of HB 14 and associated legislation, Texas is now positioned to lead a nuclear renaissance that is rightly seen as imperative for the energy security and national security of the United States.”

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A version of this article first appeared on EnergyCapitalHTX.com.

Microsoft partners with Rice University's OpenStax on AI teaching tool

group project

Rice University’s OpenStax and Microsoft are partnering to integrate the nonprofit’s content with the tech giant’s AI innovation, known as Learning Zone.

“At OpenStax, our mission is to make an amazing education accessible to all,” Richard G. Baraniuk, founder and director of OpenStax, said in a news release. “That’s why we’re excited to integrate our trustworthy, peer-reviewed content with Microsoft’s AI technology through the Microsoft Learning Zone. Together, we aim to help more instructors and their students access engaging, effective learning experiences in new and dynamic ways. We also share a strong commitment to the thoughtful and responsible application of AI to better ensure all learners can succeed.”

OpenStax is a provider of affordable instructional technologies and is also one of the world’s largest publishers of open educational resources (OER).

Microsoft Learning Zone promises to provide educators and students with “responsible AI technology and peer-reviewed educational content to support learning” on Microsoft Copilot+ PCs. Microsoft Learning Zone works by utilizing on-device AI to generate interactive lessons for students, and its integration with OpenStax content means educators can rely on OpenStax’s digital library of 80 openly licensed titles.

The goal is for educators to create effective and engaging learning experiences safely, thereby bypassing the need to source and vet content independently. Included is a library of ready-to-use lessons, opportunity for immediate feedback and differentiated learning. Educators will maintain control of instructional content and pedagogical strategies and will be able to update or edit lessons or activities prior to sharing them with students.

Other tools included in the Microsoft Learning Zone are additional languages, reading coaching, public speaking help, math and reading progress, and a partnership with the online quiz platform Kahoot!

OpenStax resources have been reported as used across 153 countries, and this current collaboration combines the power and potential of responsible AI usage in education with content that has been utilized by 13,569 K-12 schools and 71 percent of U.S. colleges and universities, according to Rice.

“Through our partnership with OpenStax, we’re combining the power of on-device AI in Copilot+ PCs with OpenStax’s trusted and diverse peer-reviewed content to help educators quickly create high-quality, personalized, engaging lessons,” Deirdre Quarnstrom, vice president of Microsoft Education, added in the news release. “We’re excited about how this collaboration will empower classrooms globally.”