Here are some protocols and an article that my help you out...
Invitrogen. Transfecting siRNA into Mammalian Cells Using Lipofectamine™ 2000.
Introduction:
Lipofectamine™ 2000 has been used successfully to transfect short interfering RNAs (siRNA) into mammalian cells for RNA interference (RNAi) studies (Gitlin et al., 2002; Yu et al., 2002). This reference provides general guidelines and procedures to transfect siRNA into mammalian cells using Lipofectamine™ 2000. Suggested transfection conditions are provided for a number of mammalian cell lines as a starting point. If you are using these cell lines or another mammalian cell line, we recommend optimizing transfection conditions to obtain the best results for your target gene and siRNA.
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Transfecting and Plating RAW 264.7 Cells with Lipofectamine 2000. AfCS Procedure Protocol PP00000182
Version 1, 10/31/03
Overview:
The following procedure is for simultaneous transfection and plating of RAW 264.7 cells. This protocol results in approximately 50% to 70% cell viability, and of those viable cells, 20% to 40% are transfected when using pEYFP-N1 from Clontech.
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Brian Dalbyl, Sharon Cates, Adam Harris, Elise C. Ohki, Mary L. Tilkins, Paul J. Price and Valentina C. Ciccarone. Advanced transfection with Lipofectamine 2000 reagent: primary neurons, siRNA, and high-throughput applications. Methods
Volume 33, Issue 2, June 2004, Pages 95-103
Abstract:
Lipofectamine 2000 is a cationic liposome based reagent that provides high transfection efficiency and high levels of transgene expression in a range of mammalian cell types in vitro using a simple protocol. Optimum transfection efficiency and subsequent cell viability depend on a number of experimental variables such as cell density, liposome and DNA concentrations, liposomeDNA complexing time, and the presence or absence of media components such as antibiotics and serum. The importance of these factors in Lipofectamine 2000 mediated transfection will be discussed together with some specific applications: transfection of primary neurons, high throughput transfection, and delivery of small interfering RNAs.