Читать книгу Introduction to the Human Cell - Danton PhD O'Day - Страница 10

Unlike micelles, liposomes are bilayered lipid vesicles and they don’t from spontaneously. They are made by treating aqueous suspensions of phospholipids with high frequency sound (sonicating). This leads to synthetic pseudo-membranes called liposomes. If proteins are included in the suspension, then the liposomes can be formed with proteins embedded within them, just like real biological membranes. Thus the ability to make liposomes opens up a whole new area for the delivery of drugs and agents to the body. Already, liposomes are used for the delivery of cosmeceuticals—cosmetic products containing biologically active components such as bioactive peptides, hormones, and other molecules. Liposomes also function as vehicles for drug and antibody delivery. By inserting specific proteins (e.g., receptors) in the liposome, it can be targeted to specific cell types. One goal is to find or develop specific liposomal proteins that can seek out cancer cells where they can bind and fuse with them to transport chemotherapeutic or other agents into those cells to destroy them. As another example, liposomes can also be used to transfer genes or enzymes into cells to correct for the absence of specific proteins. This is being done today to treat various diseases as detailed later in this book.