Preparation of chitin‐CdTe quantum dots films and antibacterial effect on Staphylococcus aureus and Pseudomonas aeruginosa

Abstract

Novel chitin–cadmium‐tellurium quantum dot (Chitin‐CdTeQD) hybrid films combining chitin and CdTe quantum dots (CdTeQDs) were prepared via a facile aqueous synthesis route at room temperature. Films were characterized by high‐resolution field emission scanning electron microscopy (HR‐FESEM) and energy dispersive X‐ray (EDX) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and X‐ray diffraction analysis (XRD). Antibacterial activity was studied on both Gram‐positive (Staphylococcus aureus) and Gram‐negative (Pseudomonas aeruginosa) bacteria. Antibacterial properties were investigated with agar diffusion testing assay and with confocal laser scanning microscopic image analysis. Chitin–CdTeQD films exhibited an excellent antibacterial activity against both Gram‐positive and Gram‐negative bacteria. Chitin–CdTeQD films might be a desirable antibacterial material for wide range of biomedical applications including wound dressing, burn treatment, drug delivery systems, packaging, ophthalmology, and implants. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44904.

Preparation of aerochitin‐TiO2 composite for efficient photocatalytic degradation of methylene blue

“…The bands in the range of 1154–1027 cm −1 are caused by the asymmetric bridge oxygen and CO stretching. Our results are in agreement with the reported literature values for α‐chitin . The adsorption band at 898 cm −1 is much clearer and sharper in the FTIR spectrum of the composite material.…”

Cotton Cellulose-CdTe Quantum Dots Composite Films with Inhibition of Biofilm-Forming S. aureus

“…Cellulose-CdTe QDs composite films were prepared using a slightly modified method [44]. First, the crushed cellulose powder (5% w/w) was dispersed in a 100 mL of NaOH/Urea/H 2 O solution (11:4:80% (w/w)) and stirred for 20 min.…”

“…Gram-positive S. aureus GFP AH133 strain was grown in Luria Bertani (LB) broth or on LB agar plates at 37 • C with shaking (250 rpm). The strain carries plasmid pCM11 in which the gene that codes for green fluorescent protein (GFP) is constitutively expressed [44,47]. To maintain the plasmid pCM11 in S. aureus GFP AH133, 1 µg/mL erythromycin (AH133) was added to the LB broth.…”

“…The zone of inhibition of S. aureus by cellulose-CdTe QDs composite films was evaluated using an agar diffusion assay as described earlier [44,47]. First, the S. aureus strain was grown in LB broth supplemented with erythromycin at 37 • C overnight with shaking.…”

“…The typical diameter of a quantum dot is in the range of 1-10 nanometers [43]. Recently, the antibacterial effect of QDs against gram-positive multi-drug resistance (MDR) bacteria such as S. aureus has also been reported [33,34,44]. However, there has been a great deal of concern over the use of QDs in living cells due to their poor biocompatibility, self-agglomeration, and instability in solution.…”