DOTMA:DOPE (50:50) Liposomes (CAT#: LDLY-0123-LY193)

DOTMA:DOPE (50:50) liposomes consist of an equal molar mixture of DOTMA, a cationic lipid, and DOPE, a neutral helper lipid. This composition is specifically designed to enhance the delivery of nucleic acids, such as DNA and RNA, into cells by neutralizing the negative charge of the nucleic acids through electrostatic interactions, thereby facilitating their cellular uptake.

Nucleic acids can be efficiently loaded into DOTMA:DOPE liposomes through a process known as complexation, where the negatively charged nucleic acids interact electrostatically with the positively charged liposomes. This process is usually performed at room temperature, with careful titration of nucleic acid to achieve the desired charge ratio.

The pH sensitivity of DOTMA:DOPE liposomes is crucial for their gene delivery capabilities. Upon encountering the acidic environment inside endosomes, these liposomes undergo a pH-dependent conformational change that promotes endosomal membrane destabilization and subsequent release of their genetic cargo into the cytoplasm, which is a critical step for successful gene expression​.

Membrane fusion is a key mechanism through which DOTMA:DOPE liposomes deliver their cargo into cells. After endocytosis, the fusogenic property of DOPE facilitates the fusion of liposomes with endosomal membranes, leading to the release of the encapsulated nucleic acids into the cytoplasm, where they can exert their biological effects.

The transfection efficiency of DOTMA:DOPE liposomes can be evaluated using a reporter gene assay, such as luciferase or GFP, where the expression level of the reporter gene in the target cells indicates the success of nucleic acid delivery. Quantitative PCR and flow cytometry are also commonly used methods to assess transfection efficiency.