Which of the following techniques are used in the isolation of Liposomal fractions?

(a) Electrophoresis

(b) Ultracentrifugation

(c) Sucrose density gradient centrifugation

(d) All of the above

(d) All of the above

All three techniques are used in the complete workflow of isolating and analyzing lysosomal fractions from a cell. The process typically involves a sequence of steps:

1. Ultracentrifugation: The first step is usually differential centrifugation, a type of ultracentrifugation. A cell homogenate is spun at increasing speeds, causing larger and denser components to form a pellet first. Lysosomes are typically found in a "light mitochondrial" fraction, which also contains mitochondria and peroxisomes.
2. Sucrose density gradient centrifugation: To purify the lysosomes from this mixed fraction, sucrose density gradient centrifugation is used. The sample is layered onto a tube containing a sucrose solution of varying density and centrifuged again. The lysosomes, mitochondria, and peroxisomes separate into distinct bands based on their specific densities, allowing for the pure isolation of the lysosomal fraction.
3. Electrophoresis: After isolation, electrophoresis (such as SDS-PAGE followed by Western blotting) is used as an analytical tool. It helps to verify the purity of the isolated lysosomal fraction by detecting the presence of specific lysosomal marker enzymes (like Acid Phosphatase) and the absence of markers from other organelles.