lost. Physical instability is the major challenge with colloidal nanoparticle systems
and, typically, surfactants and/or polymers are used to stabilize the
nanosuspensions for better drug efficacy. Biological stability of the nanocarrier is
yet another important concern for better efficacy of the drug. This could be
conferred by chemical modifications such as crosslinking and surface passivation
but, most of all, the stability of the drug carrier is an inherent characteristic of the
material used. The better the integrity of the carrier, the better it can hold the drug
under storage and host conditions.
1.4 Circulation
Characteristic material properties such as surface charge, size, and hydrophilicity
influence the circulation of a drug carrier in the blood stream [13]. These properties
of a drug carrier can be engineered for better outcome. The extent of circulation is
commonly expressed by the drug “bioavailability”. Most of the hydrophobic drugs
have a very short circulation time in vivo due to their rapid clearance, resulting in
low bioavailability. Hence, the longer the circulation time of the drug carrier, the
better the availability of the drug at the site of action.
Most of the above-mentioned essential hallmarks are well satisfied by drug
carriers made from biopolymers [14]. The diversity of biopolymers, including
proteins and carbohydrates, offers a wide range of materials with varied
characteristics to choose from viz., degradability, non-antigenicity, nutritional
value, abundance, drug-binding capacity, simple chemical structure, etc., all of
which provide platforms for an array of manipulations. These exceptional
characteristics together with the GRAS (generally regarded as safe) approval of
many of the biopolymers make them ideal matrices for drug loading and delivery.
Moreover, nanoparticles developed from proteins and carbohydrates can be easily
prepared and scaled-up during manufacture, and is also cost-effective, thereby
offering tremendous potential for industrial translation. In this chapter, we present
an extensive review of various carbohydrates and proteins used to prepare
nanomedicines, with a focus on their physicochemical features, formulational
aspects, and toxicological behavior. The carbohydrate and protein drug carriers
will be assessed on the basis of the above-stated essential hallmarks, their
contributing factors, and benefits.
2 Properties of Carbohydrates and Proteins as Drug
Delivery Systems
Carbohydrates (the building blocks) and proteins (the working machinery) of
living cells have recently been of great interest to the pharmaceutical industry
and research for developing drug delivery systems, mainly owing to their
244
D. Narayanan et al.
and, typically, surfactants and/or polymers are used to stabilize the
nanosuspensions for better drug efficacy. Biological stability of the nanocarrier is
yet another important concern for better efficacy of the drug. This could be
conferred by chemical modifications such as crosslinking and surface passivation
but, most of all, the stability of the drug carrier is an inherent characteristic of the
material used. The better the integrity of the carrier, the better it can hold the drug
under storage and host conditions.
1.4 Circulation
Characteristic material properties such as surface charge, size, and hydrophilicity
influence the circulation of a drug carrier in the blood stream [13]. These properties
of a drug carrier can be engineered for better outcome. The extent of circulation is
commonly expressed by the drug “bioavailability”. Most of the hydrophobic drugs
have a very short circulation time in vivo due to their rapid clearance, resulting in
low bioavailability. Hence, the longer the circulation time of the drug carrier, the
better the availability of the drug at the site of action.
Most of the above-mentioned essential hallmarks are well satisfied by drug
carriers made from biopolymers [14]. The diversity of biopolymers, including
proteins and carbohydrates, offers a wide range of materials with varied
characteristics to choose from viz., degradability, non-antigenicity, nutritional
value, abundance, drug-binding capacity, simple chemical structure, etc., all of
which provide platforms for an array of manipulations. These exceptional
characteristics together with the GRAS (generally regarded as safe) approval of
many of the biopolymers make them ideal matrices for drug loading and delivery.
Moreover, nanoparticles developed from proteins and carbohydrates can be easily
prepared and scaled-up during manufacture, and is also cost-effective, thereby
offering tremendous potential for industrial translation. In this chapter, we present
an extensive review of various carbohydrates and proteins used to prepare
nanomedicines, with a focus on their physicochemical features, formulational
aspects, and toxicological behavior. The carbohydrate and protein drug carriers
will be assessed on the basis of the above-stated essential hallmarks, their
contributing factors, and benefits.
2 Properties of Carbohydrates and Proteins as Drug
Delivery Systems
Carbohydrates (the building blocks) and proteins (the working machinery) of
living cells have recently been of great interest to the pharmaceutical industry
and research for developing drug delivery systems, mainly owing to their
244
D. Narayanan et al.