6.   Convertible Promissory Note Receivable

On October 1, 2020, the Company entered into a master services agreement with Safi Biosolutions, Inc. (“Safi”). In addition, the Company invested $1.5 million in Safi in the form of a convertible promissory note (the "Note"). The Note bears interest at the rate of 5% per annum and is convertible into shares of Safi’s common stock (as defined). Principal and accrued interest mature on October 1, 2023.  For the three months ended September 30, 2021, interest income amounted to $19,000. As of September 30, 2021 and June 30, 2021, the Note balance and accrued interest totaled $1,575,000 and $1,556,000, respectively.

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