Life Technologies Inc. yesterday posted a 3 percent gain in earnings for the second quarter.

The Rockville-based supplier to the life science research and biotechnology industries reported earnings of $9.76 million for the three months that ended June 30, up from $9.45 million in the second quarter of 1998.

Diluted earnings per share were 39 cents, unchanged from the corresponding period last year and below analysts' expectations of 42 cents a share.

Revenue in the quarter was $100.3 million, up from $92.2 million in the second quarter of 1998.

Eric Winzer, chief financial officer, said earnings would have been higher were it not for increased legal expenses, the cost of implementing a new computer system and losses related to the recent acquisition of a chromatography business.

"While our first half [of this year] reflected our goals, the second quarter did not reflect the earnings we would like to report," Winzer said.

He said the company will take some "belt-tightening" measures to cut expenditures with the aim of achieving long-term goals of 10 percent sales growth and a 15 percent gain in net income. But Winzer said no major plans have been made.

For the first six months, Life Technologies posted net income of $20.2 million, 12 percent more than in the corresponding period a year earlier. Revenue for the period was $200.3 million, an increase of 11 percent.

Diluted earnings per share for the six months were 81 cents, an increase of 8 percent over the first six months of last year.

Life Technologies shares closed unchanged yesterday at $38.

Life Technologies has nearly 1,800 employees worldwide, about 500 of them in Maryland.