Microbiological Associates, a division of the Whittaker Corp., will become the first corporate tenant of a new park in Montgomery County to be developed exclusively for biomedical research, county officials announced last week.

County officials earlier this week approved an $8.5 million tax-exempt industrial revenue bond to finance construction of a new headquarters and research laboratory for Microbiological at the Shady Grove Life Science Center, bordered by Maryland Route 28 and Shady Grove Road.

The 170-acre, publicly owned park which was originally called the Shady Grove Medical Park, is being developed in the hope of making it one of the nation's leading medical science research centers.

Although details of the financing have yet to be worked out with a lending institution, Microbiological expects to begin construction this fall and plans to occupy the facility early next year. The company will occupy a 7 1/2-acre site to be developed in three phases under a lease-purchase agreement with the county.

Microbiological's move from its present location in Bethesda is a major step for the county in its year-long effort to develop the Shady Grove tract. Several acres have already been reserved for direct health care institutions, including the Shady Grove Adventist Hospital and the Psychiatric Institute.

Ioanna Morfessis, director of Montgomery County's Office of Economic Development called Microbiological's decision to locate at the center "the beginning of a new era" in the county.

Montgomery County Executive Charles Gilchrist said the center "represents the county's best efforts to retain and attract what we believe is one of our major sources of new jobs and tax revenue in the future."

Microbiological's operations at the Shady Grove complex are expected to produce at least $150,000 annually in revenues for the county. The firm currently employs about 180 persons but projects a work force of 350 by 1985.

Microbiological is a biomedical research and testing company specializing in the research of cancer causes and prevention, toxicology, immunology and infectious disease diagnosis. It is one of five divisions of Whittaker Corp., a diversified health sciences company which also has interests in metals, technology, marine and chemical operations.