Does anyone know how asymmetric liposome works? asymmetric liposome

Asymmetric liposomes have different lipids in outer and inner leaflets, which would greatly increase the flexibility of vesicle in drug delivery systems. It has been well known that the phospholipid distribution in natural membranes is asymmetric. For example, phosphatidyl tcholine and sphingomyelin concentrate at the outer leaflet whereas phosphatidylethanolamine, phosphatidylinositol and phosphatidylserine are mainly localized in the inner leaflet. Typically, Lipids are self-assembled symmetrically in artificial liposomes regardless of the preparation methods. As drug delivery carriers, asymmetric liposomes with advanced functions are appealing candidates for targeted accumulation and controlled drug release. Their outer and inner leaflet could be manipulated depending on the nature of encapsulated drug molecules. For example, asymmetric liposomes help deliver negatively charged siRNA to target organs by having positively charged inner layer that encapsulates siRNA with high efficiency, and negatively charged outer surface prevents nonspecific uptake of the asymmetric liposomes. The unique tunability of asymmetric liposomes opens a wide door for multi-site functionalization, resulting in highly engineered liposomes as advanced drug delivery vesicles

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.

i dont know it at allnow im just getting points at this pint