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Synthesis and antimicrobial activity of some novel cross-linked chitosan hydrogels.

Mohamed NA, Fahmy MM - Int J Mol Sci (2012)

Bottom Line: Their structures were confirmed by fourier transform infrared X-ray (FTIR), scanning electron microscopy (SEM) and X-ray diffraction.The prepared hydrogels showed much higher antimicrobial activities than that of the parent chitosan.Increasing the degree of cross-linking in the hydrogels resulted in a weaker antimicrobial activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Faculty of Science, Cairo University, Giza 12613, Egypt; E-Mail: m.fahmy17@yahoo.com.

ABSTRACT
Four novel hydrogels based on chitosan were synthesized via a cross-linking reaction of chitosan with different concentrations of oxalyl bis 4-(2,5-dioxo-2H-pyrrol- 1(5H)-yl)benzamide. Their structures were confirmed by fourier transform infrared X-ray (FTIR), scanning electron microscopy (SEM) and X-ray diffraction. The antimicrobial activities of the hydrogels against two crop-threatening pathogenic fungi namely: Aspergillus fumigatus (A. fumigatus, RCMBA 06002), and Aspergillus niger (A. niger, RCMBA 06106), and five bacterial species namely: Bacillis subtilis (B. subtilis, RCMBA 6005), Staphylococcus aureus (S. aureus, RCMBA 2004), Streptococcus pneumoniae (S. pneumonia, RCMB 000101) as Gram positive bacteria, and Salmonella typhimurium (S. typhimurium, RCMB 000104), and Escherichia coli (E. coli, RCMBA 5003) as Gram negative bacteria have been investigated. The prepared hydrogels showed much higher antimicrobial activities than that of the parent chitosan. The hydrogels were more potent in case of Gram-positive bacteria than Gram-negative bacteria. Increasing the degree of cross-linking in the hydrogels resulted in a weaker antimicrobial activity.

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Synthesis of chitosan hydrogels (H0.5–H5).
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f4-ijms-13-11194: Synthesis of chitosan hydrogels (H0.5–H5).

Mentions: In the present work, oxalyl bis 4-(2,5-dioxo-2H-pyrrol-1(5H)-yl)benzamide was used as a cross-linking agent to modify chitosan. Chitosan (10 mmol) was reacted with four different concentrations of the cross-linker (0.5, 1.0, 2.5, and 5 mmol) via ring opening of its maleimide moieties with the amino groups of chitosan to give four cross-linked chitosan hydrogels designated as H0.5, H1.0, H2.5, and H5 of increasing cross-linking degree, respectively (Scheme 1).


Synthesis and antimicrobial activity of some novel cross-linked chitosan hydrogels.

Mohamed NA, Fahmy MM - Int J Mol Sci (2012)

Synthesis of chitosan hydrogels (H0.5–H5).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3472739&req=5

f4-ijms-13-11194: Synthesis of chitosan hydrogels (H0.5–H5).
Mentions: In the present work, oxalyl bis 4-(2,5-dioxo-2H-pyrrol-1(5H)-yl)benzamide was used as a cross-linking agent to modify chitosan. Chitosan (10 mmol) was reacted with four different concentrations of the cross-linker (0.5, 1.0, 2.5, and 5 mmol) via ring opening of its maleimide moieties with the amino groups of chitosan to give four cross-linked chitosan hydrogels designated as H0.5, H1.0, H2.5, and H5 of increasing cross-linking degree, respectively (Scheme 1).

Bottom Line: Their structures were confirmed by fourier transform infrared X-ray (FTIR), scanning electron microscopy (SEM) and X-ray diffraction.The prepared hydrogels showed much higher antimicrobial activities than that of the parent chitosan.Increasing the degree of cross-linking in the hydrogels resulted in a weaker antimicrobial activity.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Faculty of Science, Cairo University, Giza 12613, Egypt; E-Mail: m.fahmy17@yahoo.com.

ABSTRACT
Four novel hydrogels based on chitosan were synthesized via a cross-linking reaction of chitosan with different concentrations of oxalyl bis 4-(2,5-dioxo-2H-pyrrol- 1(5H)-yl)benzamide. Their structures were confirmed by fourier transform infrared X-ray (FTIR), scanning electron microscopy (SEM) and X-ray diffraction. The antimicrobial activities of the hydrogels against two crop-threatening pathogenic fungi namely: Aspergillus fumigatus (A. fumigatus, RCMBA 06002), and Aspergillus niger (A. niger, RCMBA 06106), and five bacterial species namely: Bacillis subtilis (B. subtilis, RCMBA 6005), Staphylococcus aureus (S. aureus, RCMBA 2004), Streptococcus pneumoniae (S. pneumonia, RCMB 000101) as Gram positive bacteria, and Salmonella typhimurium (S. typhimurium, RCMB 000104), and Escherichia coli (E. coli, RCMBA 5003) as Gram negative bacteria have been investigated. The prepared hydrogels showed much higher antimicrobial activities than that of the parent chitosan. The hydrogels were more potent in case of Gram-positive bacteria than Gram-negative bacteria. Increasing the degree of cross-linking in the hydrogels resulted in a weaker antimicrobial activity.

Show MeSH
Related in: MedlinePlus