Transcript Chitosan Nanoparticles as Drug Carriers

Chitosan Nanoparticles as
Drug Carriers
By: Yue Yu
BioE@UIC
Chitosan Nanoparticles (CSNPs)
A Promising Drug Delivery System
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Stability in nano-scale
Low toxicity
Excellent biocompatibility
Simple and mild preparation method
Versatile routes of administration
Sub-micron size for non-invasive route
Note: The most popular “non-invasive route” is the “mucosal” routes of
administration, such as oral, nasal, and ocular mucosa, which will be
facilitated by chitosan absorption enhancing effect.
Eur. J. Pharm. Sci. 4: 23-31
Why Nano?
Conventional
Dosage Forms
Only a small amount of
administered dose reaches
the target site, while the
majority of the drug
distributes throughout the
rest of the body in
accordance with its
physicochemical and
biochemical properties.
Kumar and Banker, 2001
Novel Dosage Forms
Sub
micron
DDS
Some technical
limitations including
poor reproducibility
Liposome and stability, and low
drug entrapment
efficiency
Better reproducibility
and stability profiles,
Polymeric
high efficiency to
NPs
reach the target site,
and targeted drug
delivery with optimal
drug release profiles
Intro –NPs in Pharmaceuitics
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Nanoparticles: Solid colloidal particles with diameters ranging
from 1-1000 nm. They can be used therapeutically as adjuvant in
drug carriers in which the active ingredient is dissolved, entrapped,
encapsulated, adsorbed or chemically attached. Polymers used to
form NPs can be both synthetic and natural polymers. There are
two types of NPs: “nanospheres” and “nanocapsules”. Nanospheres
have a monolithic-type structure (matrix) in which drugs are
dispersed or adsorbed onto their surfaces. Nanocapsules exhibit a
membrane-wall structure and drugs are entrapped in the core or
adsorbed onto their exterior.
Naresuan University Journal 2003; 11(3): 51-66
Why Chitosan (CS)?
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Do you know? Among water-soluble polymers available, CS is
one of the most extensively studied. CS is a modified natural
carbohydrate prepared by the partial N-deacetylation of chitin, a
natural biopolymer derived from crustacean shells such as crabs,
shrimps1. It is also found in some microorganisms, yeast and fungi.
Because CS possesses some ideal properties of polymeric carriers
for nanoparticles (See next slide). It possesses positively charge
and exhibits absorption enhancing effect. CSNPs have been
extensively developed and explored for pharmaceutical
applications2,3.
CS has been widely employed in pharmaceutical and biomedical
fields owing to its unique properties such as non-toxicity,
biocompatibility, and biodegradability. These characteristics make
chitosan an excellent candidate for various biomedical applications
such as drug delivery, tissue engineering, and gene delivery.
1. Illum, 1998
2. LeHoux and Grondin, 1993
3. Peniston and Johnson, 1980
Table1. Criteria for ideal polymeric carriers for
nanoparticles & nanoparticle delivery systems
Polymeric carriers
Nanoparticle delivery systems
Easy to synthesize and characterize
Simple and inexpensive to manufacture and scaleup
Inexpensive
No heat, high shear forces or organic solvents
involved in their preparation process
Biocompatible
Reproducible and stable
Biodegradable
Applicable to a broad category of drugs; small
molecules, proteins and polynucleotides
Non-immunogenic
Ability to lyophilize
Non-toxic
Non-toxic
Water soluble
Stable after administration
Naresuan University Journal 2003; 11(3)
Intro of Preparation method
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CSNPs preparation technique has been developed based
on chitosan microparticles technology. There are at least
four methods available: ionotropic gelation,
microemulsion, emulsification solvent diffusion and
polyelectrolyte complex. The most widely developed
methods are ionotropic gelation and self assemble
polyelectrolytes. These methods offer many advantages
such as simple and mild preparation method without the
use of organic solvent or high shear force. In general,
the factors found to affect nanoparticles formation
including particle size and surface charge are molecular
weight and degree of deacetylation of chitosan. The
entrapment efficiency is found to be dependent on the
pKa and solubility of entrapped drugs. The drug is
mostly found to be associated with chitosan via
electrostatic interaction, hydrogen bonding, and
hydrophobic interaction.
Waree Tiyaboonchai, 2003
Applications of CSNPs
Non-viral gene delivery vectors
 Parenteral administration
 Peroral administration
 Ocular administration
 Delivery of vaccines
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Bender et al., 1996; Page-Clisson et al., 1998; Soma et al., 2000
Gerlowski and Jain, 1986; Sadzuka et al., 1998
Norris et al,. 1998; Takeuchi et al., 2001
Pan et al., 2002 ; Vila et al., 2002
Folate-CS-DNA NPs
for gene therapy
Sania Mansouri, 2006
The mechanism of folic acid (FA) uptake by cells to
promote targeting and internalization could improve
transfection rates. FA-CS-DNA NPs were prepared
using reductive amidation and a complex
coacervation process. The aim of the study was to
synthesize and characterize FA-CS-DNA NPs and to
evaluate their effect on cell viability. The paper shows
that FA-NPs have lower cytoxicity, good DNA
condensation, positive zeta potential (an abbreviation
for electrokinetic potential in colloidal systems) and
particle size around 118 nm, which makes them a
promising candidate as a non-viral gene vector.
Charge ratio (N/P) controlled the nanoparticles size
and their zeta potential.
Relationship between N/P charge ratio
and particle size and zeta potential:
Sania Mansouri, 2006
When the charge ratio of FA-chitosan-DNA nanoparticles is around 1, the
nanoparticle size is more than 300nm. If the charge ratio increases, the
nanoparticles size decreases to the 120 nm range.
With an electrophoresis gel, the plasmid
DNA condensation and integrity can be
Sania Mansouri, 2006
shown:
This Figure illustrates an intact DNA, before nanoparticle
synthesis (lane 1). The DNA in lanes 2 and 3-3a is unable to
migrate and remains in the gel loading wells. Following
digestion with chitosanase and lysozyme, the plasmid DNA
was released from the nanoparticles and could be viewed in
lanes 4 and 5-5a.
Chitosan nanoparticle as
protein/Genes delivery carrier
Methods of preparation
Drugs/Proteins/Genes
CSNPs systems Ionic
gelation
Insulin, BSA, cyclosporine A
Coacervation
DNA
Precipitation Emulsiondroplet
Coalescence Reverse
micellar
Self-assembly chemical
modification
Quan, 2007
Gadopentetic acid
Doxorubicin
Deoxycholic acid
Hydrophobically modified glycol
chitosan (HGC) as carriers for
paclitaxel
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Paclitaxel (PTX), an anticancer agent extracted from the
bark of the Pacific yew (Taxus brevifolia), has demonstrated
significant activity in clinical trials against a variety of
tumors. However, PTX is a hydrophobic drug with poor
aqueous solubility. To increase its solubility HGC was
prepared as a carrier.
HGC conjugates were prepared by chemically linking 5βcholanic acid to glycol chitosan chains.
In phosphate-buffered saline, the synthesized HGC
conjugates formed nano-sized particles with a diameter of
200 nm and exhibited high thermodynamic stability.
Paclitaxel was efficiently loaded into HGC nanoparticles up
to 10 wt.% using a dialysis method.
Jong-Ho Kim, 2006
The chemical structure of the
HGC conjugate is shown below:
HGC nanoparticles show promise as carriers for anticancer
peptides and anticancer drugs because they are
biocompatible in vivo and accumulate passively in tumor
tissue.
Jong-Ho Kim, 2006
The average mean diameter of HGC and PTX-HGC NPs were
evaluated at 633 nm and 25 oC. The anti-tumor efficacy of
PTX-HGC nanoparticles was evaluated in tumor-bearing mice.
The survival and the body weight of the mice were recorded.
Below is the transmission electron microscopy (TEM) image
of HGC alone (left) and PTX-HGC nanoaggregates (right):
PTX was loaded into HGC nanoparticles using a simple
dialysis method. The size of the PTX-HGC nanoparticles
increased after drug loading from 200 to 400 nm, but the
size distribution remained narrow.
Jong-Ho Kim, 2006
Deoxycholic acid-conjugated
CSNPs (COSDs) for gene carrier
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As efficient gene carriers, the COSDs showed
superior gene condensation and protection of
condensed gene from endonuclease attack.
COSDs showed great potential for gene carrier
with the high level of gene transfection
efficiencies.
The highly purified COSs, with the average
molecular weight of 3000 and 6000 Da, were
chemically modified by deoxycholic acid (DOCA).
The synthetic schemes for DOCA conjugation on COSs
is shown below:
Su Young Chae, 2005
N-trimethyl chitosan chloride (TMC)
nanoparticles as protein carriers
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TMC nanoparticles were prepared by ionic crosslinking with
tripolyphosphate (TPP).
TMC, a chitosan derivative, shows perfect solubility in water over a
wide pH range. It also has bioadhesive properties and
enhancement of permeability and absorption in neutral and basicpH environments.
TMC nanoparticles could be prepared by a mild ionic gelation
procedure and proved that they are safe carriers for nasal protein
delivery.
Two model proteins with similar molecular weight (Mw = 68, 000
Da) but different pI values, bovine serum albumin (BSA, pI = 4.8)
and bovine hemoglobin (BHb, pI = 6.8), were to investigate the
protein loading and release profiles of TMC nanoparticles.
Fu Chen, 2007
TMC precipitation efficacy (PE) can be calculated as
follows:
Loading efficiency and loading capacity can be
calculated as follows:
Fu Chen, 2007
TMC precipitation efficacy as a function of TPP concentration
(TMC 2 mg/ml, TPP 0.1–0.9 mg/ml). Data shown are the
mean±S.D. (n = 3). TMC33 (▲) and TMC37 (■).
Fu Chen, 2007
Fu Chen, 2007
TEM of non-loaded TMC nanoparticles (A), BSA-loaded TMC
nanoparticles (B), BHb-loaded TMC nanoparticles (C) and alginate
modified nanoparticles (D). (TMC 372mg/ml, TPP 0.6mg/ml, BSA
or BHb 0.4mg/ml, sodium alginate 0.3mg/ml). This figure shows
the morphology of protein-loaded and nonleaded TMC NPs.
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Table 1 shows the effect of the initial protein
concentration on the LE and LC of the TMC
nanoparticles. The high loading efficiency of BSA
could be due to the ionic interaction between
TMC and BSA. Too high a BSA concentration
could lead to aggregation. The influence of the
degree of quaternization of TMC on the particle
size and zeta potential is shown in Table 2.
Nanoparticles prepared by TMC33 showed a
larger size and PDI, and a lower zeta potential
than those prepared with TMC37 for both loaded
and non-loaded formations.
Fu Chen, 2007
The figure below compares the permeate efficiency
of modified and non-modified TMC nanoparticles,
alginate modified TMC nanoparticles at low
(5mg/ml) concentration and high (20mg/ml)
concentration :
Fu Chen, 2007
References:
1. Characterization of folate-chitosan-DNA nanoparticles for gene therapy Sania
Mansouria, Yan Cuieb, Francoise Winnikb
2. Preparation and characterization of protein-loaded N-trimethyl chitosan
nanoparticles as nasal delivery system Maryam Amidi, Stefan G. Romeijn
3. Preparation and evaluation of nanoparticles made of chitosan or N-trimethyl
chitosan and a cisplatin–alginate complex S. Cafaggi, E. Russo, R. Stefani
4. Preparation and modification of N-(2-hydroxyl) propyl-3-trimethyl ammonium
chitosan chloride nanoparticle as a protein carrier Yongmei Xu, Yumin Du
5. Evaluation and modification of N-trimethyl chitosan chloride nanoparticles as
protein carriers Fu Chen, Zhi-Rong Zhang
6. Chitosan nanoparticle as protein delivery carrier - Systematicexamination of
fabrication conditions for efficient loading and release Quan Gan, Tao Wang
7. Chitosan nanoparticles as delivery systems for doxorubicin Kevin A. Janes,
Marie P. Fresneau
8. Hydrophobically modified glycol chitosan nanoparticles as carriers for paclitaxel
Jong-Ho Kim, Yoo-Shin Kim, Sungwon Kim
9. Microencapsulated chitosan nanoparticles for lung protein delivery Ana Grenha,
Begona Seijo
10. In vitro and in vivo study of N-trimethyl chitosan nanoparticles for oral protein
delivery Fu Chen, Zhi-Rong Zhang, Fang Yuan