evaluated in M. tuberculosis H37Rv-infected mice. High drug encapsulation efficiency was achieved in alginate nanoparticles, ranging from 70% to 90%. A single
oral dose resulted in therapeutic drug concentrations in the plasma for 7–11 days
and in the organs (lungs, liver and spleen) for 15 days. In comparison to free drug
(which were cleared from plasma and organs within 12–24 h), there was a significant enhancement in the relative bioavailability of encapsulated drugs. In TB‐
infected mice, three oral doses of the formulation spaced 15 days apart resulted in
complete bacterial clearance from the organs, compared to 45 conventional doses
of orally administered free drug.
6.4.2 Sodium Alginate–Chitosan Composite Films for Fabrication
of Antibacterial Silver Nanoparticles
A new and simple ecofriendly method for the synthesis of silver nanoparticles (Ag
NPs) using a natural biopolymer, sodium alginate, as both reducing and stabilizing
agent has been reported. The synthesized NPs were characterized using UV–vis
spectroscopy, TEM and selected area electron diffraction (SAED) pattern. The
alginate-capped NPs (Alg–Ag NPs) were found to be antibacterial. The Alg–Ag
NPs were blended with varying amounts of chitosan to form polyelectrolyte
complexes that were cast into stable films. The films were characterized by field
emission scanning electron microscopy (FESEM), optical microscopy, Fourier
transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The water
uptake and mechanical properties of the films were also studied. The blended films
demonstrated excellent antibacterial activity against both Gram-negative and
Gram-positive bacteria, with more activity against Gram-positive bacteria. Thus,
the developed films have a potential to be used for various antibacterial applications
in biotechnology and biomedical fields.
6.5 Applications of Gelatin Nanoparticles
6.5.1 Nonviral Gene Delivery Vectors
Cationized gelatin nanoparticles have shown the potential of being a new effective
carrier for nonviral gene delivery. The major benefit of gelatin nanoparticles is not
only the very low cell toxicity, but also their simple production, combined with low
cost. Native gelatin nanoparticles were prepared by a two-step desolvation technique. In order to bind DNA by electrostatic interaction onto the surface of the
particles, the quartenary amine cholamine was covalently coupled to the particles.
The modified nanoparticles were loaded with different amounts of plasmid in
varying buffers and compared to polyethyleneimine–DNA complex as a standard.
Transfection ability of the loaded nanoparticles was tested on B16F10 cells.
Additionally, the cell toxicity of the formulation was monitored. Different setups
resulted in efficient gene delivery, displayed by an exponential increase in gene
expression. The gene expression itself occurred with a certain delay after
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oral dose resulted in therapeutic drug concentrations in the plasma for 7–11 days
and in the organs (lungs, liver and spleen) for 15 days. In comparison to free drug
(which were cleared from plasma and organs within 12–24 h), there was a significant enhancement in the relative bioavailability of encapsulated drugs. In TB‐
infected mice, three oral doses of the formulation spaced 15 days apart resulted in
complete bacterial clearance from the organs, compared to 45 conventional doses
of orally administered free drug.
6.4.2 Sodium Alginate–Chitosan Composite Films for Fabrication
of Antibacterial Silver Nanoparticles
A new and simple ecofriendly method for the synthesis of silver nanoparticles (Ag
NPs) using a natural biopolymer, sodium alginate, as both reducing and stabilizing
agent has been reported. The synthesized NPs were characterized using UV–vis
spectroscopy, TEM and selected area electron diffraction (SAED) pattern. The
alginate-capped NPs (Alg–Ag NPs) were found to be antibacterial. The Alg–Ag
NPs were blended with varying amounts of chitosan to form polyelectrolyte
complexes that were cast into stable films. The films were characterized by field
emission scanning electron microscopy (FESEM), optical microscopy, Fourier
transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The water
uptake and mechanical properties of the films were also studied. The blended films
demonstrated excellent antibacterial activity against both Gram-negative and
Gram-positive bacteria, with more activity against Gram-positive bacteria. Thus,
the developed films have a potential to be used for various antibacterial applications
in biotechnology and biomedical fields.
6.5 Applications of Gelatin Nanoparticles
6.5.1 Nonviral Gene Delivery Vectors
Cationized gelatin nanoparticles have shown the potential of being a new effective
carrier for nonviral gene delivery. The major benefit of gelatin nanoparticles is not
only the very low cell toxicity, but also their simple production, combined with low
cost. Native gelatin nanoparticles were prepared by a two-step desolvation technique. In order to bind DNA by electrostatic interaction onto the surface of the
particles, the quartenary amine cholamine was covalently coupled to the particles.
The modified nanoparticles were loaded with different amounts of plasmid in
varying buffers and compared to polyethyleneimine–DNA complex as a standard.
Transfection ability of the loaded nanoparticles was tested on B16F10 cells.
Additionally, the cell toxicity of the formulation was monitored. Different setups
resulted in efficient gene delivery, displayed by an exponential increase in gene
expression. The gene expression itself occurred with a certain delay after
292
A.K. Anal and A. Tuladhar