The bid of $13 per share is up from $12.25 per share and the second increase to the offer, which began at $11.75.
Shareholders were to vote on the earlier offer last week, but the meeting was postponed after it became apparent the deal wouldn't receive the required two-thirds majority approval.
"Although a clear majority of Nordion shareholders supported Sterigenics’ all-cash acquisition proposal at US$12.25 per share, there did not appear to be sufficient shareholder support to approve the transaction," the company said in a statement.
Shareholders are expected to vote Friday on the new offer by Sterigenics, an affiliate of Chicago-based private equity firm GTCR LLC.
Nordion is a leading suppliers of medical isotopes, used for certain types of medical imaging. It also provides sterilization technologies for several industries.
The new offer follows an unsolicited offer of $12.50 last week from an unidentified third party that had earlier made an offer of US$12.25, Nordion said.
Nordion also reported Monday that it had a second-quarter profit of $6.7 million or 11 cents per share, up from a profit of $731,000 or a penny per share a year ago.
Revenue for the quarter ended April 30 totalled $74.7 million, up from $56.1 million in the same three months a year earlier.
On an adjusted basis, Nordion said it earned $13.5 million or 22 cents per share for the quarter, up from $4.8 million or eight cents per share in the second quarter last year.
The company settled a bitter legal fight with Atomic Energy of Canada Ltd. last year with a new supply deal that will run until October 2016 and an agreement by both sides to drop more than $100 million in claims.
A shortage of medical isotopes occurred around the world when AECL's NRU reactor was shut down in 2009 because of a leak that took more than a year to repair.
The shortage raised concerns about the availability of medical tests and Ottawa's decision to end the Maple program, an over-budget-and-behind-schedule plan to replace the NRU reactor.Suggest a correction