Publications in March and April 2014

In March and April, 234 publications were released about Chitosan, mainly addressing topics like pharmaceutical preparations, nanoparticles, evaluation studies and tissues. The most successful nations in the field of chitosan-related publications are again: China (74 articles), India (24) and USA (19).

Top Journals	Publications
International journal of biological macromolecules	31
Carbohydrate polymers	17
Colloids and surfaces. B, Biointerfaces	13
International journal of pharmaceutics	8
Drug delivery	8

Table: List of scientific journals, which published the highest number of chitosan-related articles in March and April 2014.
Source: GoPubMed

Chitosan is a mucoadhesive polysaccharide, which gets increasing attention from the pharmaceutical and food industries. Its advantageous properties: non-toxic, antimicrobial, biocompatible and enzyme degradable, appears to be suitable to use chitosan as carrier for drugs. The following three articles analyzed different chitosan derivatives with regard to their usability as drug carrier.   

Electrosprayed 4-carboxybenzenesulfonamide-chitosan microspheres for acetazolamide delivery.

Suvannasara P., Siralertmukul K., Muangsin N., International journal of biological macromolecules. Vol. 64 :240-6. March 2014.

In the present study, authors developed a mucoadhesive drug delivery system, which consists of   4 carboxybenzensulfonamide-modified chitosan. 4-CBS-chitosan displays higher swelling capacity than unmodified chitosan and has a stronger mucoadhesion. Furthermore, it is non-toxic to cultured cells and possesses antibacterial activity against Escherichia coli and Staphylococcus aureus.   
Microspheres were prepared by electrospraying (ESI), creating uniform particle sizes. During this one-step technique, acetazolamide (ACZ) was loaded to the beads. ACZ is a carbonic anhydrase inhibitor and is used for the medical treatment of gastric and duodenal ulcers.

Results:

ACZ/ 4-CBS-chitosan: Encapsulation efficiency for ACZ: 4-CBS-chitosan 90% natives chitosan 47% Particle size: 3.1 µm Polydispersity: low (0.4), indicating less aggregation Biphasic drug release in acidic fluids initial burst release: 58 % in 5 min sustained release: 100 % over 3 h Drug release of native chitosan: 44 % over 1.5 h

 

Conclusion: Microspheres of 4-CBS-chitosan possess high drug encapsulation efficiency, small size, low aggregation rate and a biphasic pattern of drug release. 4-CBS-chitosan display superior properties over natural chitosan, in acidic conditions. Thus, 4-CBS-chitosan might be a useful drug delivery device to address the gastric environment.

Source: http://www.ncbi.nlm.nih.gov/pubmed/24360896

Spray-dried O-carboxymethyl chitosan as potential hydrophilic matrix tablet for sustained release of drug.

Bresolin JR., Largura M.C., Dalri C.C. et al., Drug Development and Industrial Pharmacy. Vol. 40 (4): 503-10. April 2014.

The objective of this study was to develop O-carboxymethyl-modified chitosan (OCMCS) powder as a hydrophilic carrier for sustained drug release. The hydrophile OCMCS powder was loaded with diltiazem (DTZ), a Ca2+ channel blocker used to treat hypertension and arrhythmia. OCMCS-DTZ powder was spray-dried and then formed into tablets by using direct compression or wet granulation method. Different concentrations of OCMCS were tested: 80, 50, 30, 2 % w/w.

Results:

• spherical shape of OCMCS particles
• smooth surface structure
• Particle size : 2.2 µm
• Tablets:
  • direct compression: high drug retention
  • wet granulation: disintegration time < 30 min
• OCMCS concentration determines drug release rate and swelling degree

Conclusion: O-carboxymethyl-chitosan possesses excellent features as a carrier for sustained drug release. By varying the OCMCS concentration and tablet preparation technique, the efficiency and time of drug release can be adapted and optimized to specific requirements.

Source: http://www.ncbi.nlm.nih.gov/pubmed/23594298

Design, synthesis and in vitro evaluation of mucoadhesive p-coumarate-thiolated-chitosan as a hydrophobic drug carriers.

Pengpong T., Sangvanich P., Sirilertmukul K., Muangsin N.; European Journal of Pharmaceutics and Biopharmaceutics, Vol. 86 (3): 487-97, April 2014.

The study aim was to develop a hydrophobic drug delivery system with a high drug entrapment and sustained rate of drug release. Chitosan was conjugated with p-coumaric acid (pCA) to enhance hydrophobic drugs entrapment. The pCA-conjugated polymers and hydrophobic compounds formed non-covalent bindings via their aromatic π-electrons. The mucoadhesion capacity of the polymer was improved by linking it with homocysteine thiolactone (HT). Thiolated polymers can tightly bind to glycoproteins in the intestinal mucus layer by forming strong disulfide bonds. Piperine (PIP) served as hydrophobic model drug and is the major alkaloid of black pepper. PIP was loaded to pCA-HT particles by electrospray ionization.

Results:

pCA-HT chitosan: 24 h conjugation reaction time: highest yield of SH-groups (17.6 µmol/g) best swelling degree high thermal stability Particle size: pCA-HT chitosan:                 2.82 µm pCA-HT chitosan / 5% PIP:   5.01 µm Encapsulation efficiency (5% PIP) > 80 % Strong mucoadhesive properties pH = 1.2:   10-fold over unmodified chitosan pH = 4.0:     2-fold pH = 6.4:  1.6-fold Drug release rate: > 75 % over 12 h Zeta-potential: - 25.24 mV to -13.70 mV, indicating moderate stability

 

Conclusion: Microspheres of pCA-HT-modified chitosan are suitable for hydrophobic drug delivery. Their improved hydrophobic drug entrapment, mucoadhesion capacity and sustained drug release allows a prolonged drug delivery into the gastrointestinal tract.

Source: http://www.ncbi.nlm.nih.gov/pubmed/24333665