LAB(2) - A LIVING MEMBRANE Flashcards
Dialysis
the process of separating small molecules from larger molecules in a soln. by selective diffusion through a semi-permeable membrane
Dialysis
mimics the cell membrane’s function of filtering and maintaining balance
- The egg membrane found just beneath the eggshell, is composed
primarily of proteins; plays a key role in protecting the egg’s contents from microbial invasion and physical damage - a natural biopolymer primarily made of protein fibers (e.g. collagen) which provide structural support
contribute to the membrane’s strength and biological functions
- lysozyme (N-acetylmuramylhydrolase)
- ovalbumin
- ovotansferirin
Glycoproteins
help maintain the maintain the elasticity and integrity of the membrane
Lipid and other minor components
contribute to the composition of the eggshell membrane’s permeability and flexibility
How does Cl- pass through the cell membrane?
- Ion channels
- Transport proteins
Explain how the ion channels let Cl- pass through the cell membrane.
Specialized proteins called chloride channels allow Cl⁻ ions to move across the membrane. These channels can be either voltage-gated (responding to changes in membrane potential) or ligand-gated (responding to specific
molecules binding to the channel).
Explain how transport proteins let Cl- pass through the cell membrane.
Some transport
proteins, like the chloride-bicarbonate
exchanger, allow the movement of Cl⁻
across the membrane in exchange for
other ions.
Hemodialysis
A type of dialysis
wherein blood is
filtered outside the
body using a dialysis
machine.
Dialyzer
act as an artificial kidney
Peritoneal dialysis
uses the lining of the abdomen as a natural filter
Dialysate fluid
introduced and later drained
What are the limitations of natural membranes in dialysis?
- Limited biocompatibility
- Inconsistent pore size
- Reduced mechanical strength
- Limited control over permeability
- Risk of contamination
- Degradation over time
- Less customizability
Explain Limited biocompatibility
Natural membranes may provoke immune responses,
leading to inflammation or rejection. This can limit their long-term use.
Explain Inconsistent pore size
The pore sizes in natural membranes can be inconsistent,
leading to less precise filtration and potentially allowing larger molecules to pass through or blocking smaller molecules.
Explain Reduced mechanical strength
Natural membranes may lack the mechanical
strength of synthetic ones, making them prone to tearing or degradation over
time.
Explain Limited control over permeability
The permeability of natural membranes can be difficult to control or modify, limiting the ability to fine-tune dialysis for
specific needs.
Explain Risk of contamination
Since natural membranes are derived from biological
sources, there is a risk of contamination with pathogens or other unwanted
biological materials.
Explain Degradation over time
Natural membranes can degrade over time due to enzymatic breakdown or other biochemical processes, which can reduce their
effectiveness and lifespan.
Explain Less customizability
Compared to synthetic membranes, natural membranes
offer less flexibility in terms of tailoring properties such as thickness, pore size,
and permeability to specific requirements.
Cellulose acetate membranes
made from cellulose acetate, these
membranes are semi-permeable
and commonly used in reverse
osmosis for water purification.
Used in desalination, dialysis, and
wastewater treatment.
Polyamide membranes
Thin, semi-permeable layers made
from polyamide are highly resistant to chlorine and are
used in various filtration processes. Used in reverse osmosis, nanofiltration, and water softening.
Polyethersulfone (PES) Membranes
hydrophilic,
strong, and thermally stable. They
have a uniform pore structure, making them suitable for various
filtration processes. Used in
microfiltration, ultrafiltration, and
biological filtration.
Polysulfone (PSU) Membranes
Known for their chemical resistance and mechanical
strength, PSU membranes are
used in demanding applications. Used in emodialysis, gas separation, and microfiltration.
