WILMINGTON, Del. – MBNA has purchased Nexstar Financial Corporation, a business outsourcer for home equity and other loans and plans to use the purchase to expand its ability to offer these products, usually branded with their affinity partner's brand, to the members of their over 5,000 affinity groups. But Ed Murphy, spokesman for the card giant, made it clear that MBNA would not be offering any MBNA products to the members of any credit unions with which it is a card issuer in an agent relationship. If a credit union came and asked MBNA to help it offer home equity loans, under its own brand, using the company's back office expertise then MBNA would consider it, Murphy explained, but the card issuing bank would not offer any MBNA branded home loans to any credit union members. Critics of credit unions selling their card portfolios to banks have speculated that one reason the banks want the portfolios is to cross sell their products to credit union members. But MBNA has always firmly resolved not to do this and has maintained that commitment even when it has said it plans to offer its product to other affinity groups, such as alumni organizations and professional societies.