ETEX Corp., an advanced biomaterials company, has signed leases totaling 28,595 square feet of office, research and manufacturing space in two locations in Cambridge.

ETEX leased 15,600 square feet of office space at One Central Plaza and renewed for 12,995 square feet of laboratory and manufacturing space at 38 Sidney St. in University Park at MIT, according to a statement. The Central Plaza lease represents the company’s expansion, which will occur in the first half of 2011.

"One Central Plaza was a great fit for ETEX in that ownership offered aggressive and flexible terms for rare high-rise office space in Cambridge that it is walking distance to their lab and manufacturing space, on top of public transportation with beautiful vistas of Cambridge and the Boston skyline," said Brendan Callahan, executive vice president, Jones Lang LaSalle.

Callahan negotiated the lease of One Central Plaza, located at 675 Massachusetts Ave., representing ETEX as the tenant, according to a statement. The building owner, Intercontinental, was represented by Jones Lang LaSalle Senior Vice Presidents John Osten and Peter Bekarian, and Associate Molly Heath.

Callahan also negotiated on behalf of ETEX at 38 Sidney St. University Park owner Forest City Enterprises Inc. was represented by Colliers Meredith & Grew Executive Vice President Joseph Flaherty and Forest City Senior Vice President Tucker Hansen.