Thus, US Food and Drug Administration (FDA) strictly regulated the conditions of
mean porosity (0.45 μm) of the membranes for the sterilization of parenteral drugs.
Additionally, membranes are also used to sterilize the air and gases used for
various applications in the health care industry. The harmful microorganisms and
particulate matter are removed from the air or gas to make it deemed to be fit for use.
Furthermore, FDA also recommended the installation of air vents and filters at places
where microorganisms are handled or controlled environment is required, which is
the requirement of bioprocess engineering in various processing and manufacturing
processes of different products. Similarly, this explains the use of vent filters as
retentive filters in case of bioreactors and fermenters.
The sterilization of the membranes is also important and should have capabilities
to be installed aseptically. Otherwise, they can infect the feed to be sterilized.
Further, the membranes should be tested for their cleanliness and sanitization prior
to use. This demand gives rise to the development of autoclavable and sterilizable
membranes for their continuous use and reuse. It is also important to note that for gas
and liquid separations, hydrophobic and hydrophilic membranes are recommended,
respectively. However, the hydrophobicity and hydrophilicity of the membranes
depend upon the nature of the feed.
3.3 Racemic and Azeotropic Separations
Sugars and amino acids are important part of bioprocess engineering. They are key
components and starting material for many important products of bioprocess industry. Therefore, there separation and purification are important as they are required to
be in their purest of form for the product formation. There are several separation
processes, including membrane separation processes, that can be used for their
separation and purification. However, the problem arises when they are present in
their chiral form. This means that the sugars or amino acids are present in their two
different enantiomer forms. Further, these enantiomers of a material consist of
similar crystalline states and chemical qualities. Thus, it is difficult to separate
such compounds with conventional separation processes. Also, only one of the
enantiomer of the compound is useful toward a particular function, and the other
might have weak functionality or would be toxic. For example, thalidomide is a
racemic drug used during pregnancy for the cure of nausea. The dexter (D) form of
thalidomide being a safe sedative is useful. However, its laevus (L) form results in
birth defects and deformities.
Membrane separation processes, such as pervaporation, ultrafiltration, and liquid
membranes are suitable for the separation of racemic and azeotropic mixtures
[1, 2]. The membranes used for this purpose are either enantioselective or
non-enantioselective. The difference between the two types of membranes is that
the enantioselective membranes are made up of enantioselector components, such as
antibodies, antigens, and enzymes. On the other hand, non-enantioselective membranes are normal membranes integrated with other chiral separation processes.
10
R. Singh et al.
mean porosity (0.45 μm) of the membranes for the sterilization of parenteral drugs.
Additionally, membranes are also used to sterilize the air and gases used for
various applications in the health care industry. The harmful microorganisms and
particulate matter are removed from the air or gas to make it deemed to be fit for use.
Furthermore, FDA also recommended the installation of air vents and filters at places
where microorganisms are handled or controlled environment is required, which is
the requirement of bioprocess engineering in various processing and manufacturing
processes of different products. Similarly, this explains the use of vent filters as
retentive filters in case of bioreactors and fermenters.
The sterilization of the membranes is also important and should have capabilities
to be installed aseptically. Otherwise, they can infect the feed to be sterilized.
Further, the membranes should be tested for their cleanliness and sanitization prior
to use. This demand gives rise to the development of autoclavable and sterilizable
membranes for their continuous use and reuse. It is also important to note that for gas
and liquid separations, hydrophobic and hydrophilic membranes are recommended,
respectively. However, the hydrophobicity and hydrophilicity of the membranes
depend upon the nature of the feed.
3.3 Racemic and Azeotropic Separations
Sugars and amino acids are important part of bioprocess engineering. They are key
components and starting material for many important products of bioprocess industry. Therefore, there separation and purification are important as they are required to
be in their purest of form for the product formation. There are several separation
processes, including membrane separation processes, that can be used for their
separation and purification. However, the problem arises when they are present in
their chiral form. This means that the sugars or amino acids are present in their two
different enantiomer forms. Further, these enantiomers of a material consist of
similar crystalline states and chemical qualities. Thus, it is difficult to separate
such compounds with conventional separation processes. Also, only one of the
enantiomer of the compound is useful toward a particular function, and the other
might have weak functionality or would be toxic. For example, thalidomide is a
racemic drug used during pregnancy for the cure of nausea. The dexter (D) form of
thalidomide being a safe sedative is useful. However, its laevus (L) form results in
birth defects and deformities.
Membrane separation processes, such as pervaporation, ultrafiltration, and liquid
membranes are suitable for the separation of racemic and azeotropic mixtures
[1, 2]. The membranes used for this purpose are either enantioselective or
non-enantioselective. The difference between the two types of membranes is that
the enantioselective membranes are made up of enantioselector components, such as
antibodies, antigens, and enzymes. On the other hand, non-enantioselective membranes are normal membranes integrated with other chiral separation processes.
10
R. Singh et al.