WILMINGTON, NC--Expanding on a major bioinformatics-related purchase earlier in the year, Pharmaceutical Product Develop ment (PPD), a contract research organization here, has announced that it is acquiring Sarco, a Durham, NC-based provider of combinatorial chemistry services, in exchange for PPD stock valued at $4.8 million. PPD is also buying the GSX System functional genomics platform technology from Ingenex, Menlo Park, Calif., for about $8.7 million in cash.