literature, the use of modified serum albumin seems promising as a selective agent for
tumour detection or therapy [19] or for delivery of toxic compounds for elimination
of Mycobacterium tuberculosis via receptor-mediated drug delivery [20]. These
exceptional characteristics of albumin have shaped a foremost place for it in
drug therapy. Therefore, nanotechnology has correspondingly engaged the wellestablished assets of albumin (both human serum albumin and bovine serum albumin)
for numerous determinations as nanoparticle drug (antibodies, interferon gamma,
antiviral compounds) carrier [21–23], therapeutic enhancer of anticancer drugs [24]
and as a modified carrier for the provision of drug from the brain to the central nervous
system and also across the blood–brain barrier [25, 26].
3.2 Collagen
Collagen is a naturally occurring protein found in animals, especially in the flesh
and connective tissues of vertebrates. It is a profusely found mammalian protein
making up about 20–30% of total body proteins. Collagen has a distinctive arrangement, size and amino acid sequence that result in the construction of triple helix
fibre. It is a beneficial biomaterial due to its tremendous compatibility, biodegradation and availability [27]. Additionally, its responsiveness to alterations have
cemented its use in nanoparticle fabrication. Modifications include addition of
other proteins, such as elastin, fibronectin and glycosaminoglycans, which results
in the improvement of its physicochemical and biological properties [28, 29] as
well as control of biodegradability and subsequent release of ligand by use of such
crosslinking agents as glutaraldehyde, formaldehyde, ultraviolet and gamma radiation. The biodegradable collagen-based nanoparticles are thermally stable, readily
sterilizable, can be uptaken by the reticulo-endothelial system and enable enhanced
uptake of drug molecules into cells [30].
3.3 Gelatin
Gelatin is a natural water-soluble macromolecule that results from the heat dissolution and incomplete hydrolysis of collagen. It is a polyampholyte, having both ionic
groups. Basically, two types of gelatin are found. Type-A gelatin is achieved by
acid treatment of collagen, with isoelectric point (pI) being between 7.0 and 9.0. In
contrast, type-B gelatin is formed through alkaline hydrolysis of collagen, with
pI between 4.8 and 5.0. Gelatin has various advantages over other synthetic
polymers, i.e., non-irritability, biocompatibility, biodegradability, non-toxicity
and non-carcinogenicity, and therefore proves to be one of the most appropriate
materials to be used as a carrier molecule [31, 32]. Gelatin has a large number of
functional groups on its surface that aid in chemical crosslinking and derivation.
These benefits have made it one of the best options for the synthesis of
nanoparticles for drug delivery for the last 30 years [33–36].
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A.K. Anal and A. Tuladhar
tumour detection or therapy [19] or for delivery of toxic compounds for elimination
of Mycobacterium tuberculosis via receptor-mediated drug delivery [20]. These
exceptional characteristics of albumin have shaped a foremost place for it in
drug therapy. Therefore, nanotechnology has correspondingly engaged the wellestablished assets of albumin (both human serum albumin and bovine serum albumin)
for numerous determinations as nanoparticle drug (antibodies, interferon gamma,
antiviral compounds) carrier [21–23], therapeutic enhancer of anticancer drugs [24]
and as a modified carrier for the provision of drug from the brain to the central nervous
system and also across the blood–brain barrier [25, 26].
3.2 Collagen
Collagen is a naturally occurring protein found in animals, especially in the flesh
and connective tissues of vertebrates. It is a profusely found mammalian protein
making up about 20–30% of total body proteins. Collagen has a distinctive arrangement, size and amino acid sequence that result in the construction of triple helix
fibre. It is a beneficial biomaterial due to its tremendous compatibility, biodegradation and availability [27]. Additionally, its responsiveness to alterations have
cemented its use in nanoparticle fabrication. Modifications include addition of
other proteins, such as elastin, fibronectin and glycosaminoglycans, which results
in the improvement of its physicochemical and biological properties [28, 29] as
well as control of biodegradability and subsequent release of ligand by use of such
crosslinking agents as glutaraldehyde, formaldehyde, ultraviolet and gamma radiation. The biodegradable collagen-based nanoparticles are thermally stable, readily
sterilizable, can be uptaken by the reticulo-endothelial system and enable enhanced
uptake of drug molecules into cells [30].
3.3 Gelatin
Gelatin is a natural water-soluble macromolecule that results from the heat dissolution and incomplete hydrolysis of collagen. It is a polyampholyte, having both ionic
groups. Basically, two types of gelatin are found. Type-A gelatin is achieved by
acid treatment of collagen, with isoelectric point (pI) being between 7.0 and 9.0. In
contrast, type-B gelatin is formed through alkaline hydrolysis of collagen, with
pI between 4.8 and 5.0. Gelatin has various advantages over other synthetic
polymers, i.e., non-irritability, biocompatibility, biodegradability, non-toxicity
and non-carcinogenicity, and therefore proves to be one of the most appropriate
materials to be used as a carrier molecule [31, 32]. Gelatin has a large number of
functional groups on its surface that aid in chemical crosslinking and derivation.
These benefits have made it one of the best options for the synthesis of
nanoparticles for drug delivery for the last 30 years [33–36].
278
A.K. Anal and A. Tuladhar