Development of antimicrobial hybrid mesoporous silver phosphateepectin microspheres for control release of levofloxacin

BAYON, BERNARDO; BUCALA, VERONICA; CASTRO, GUILLERMO

MICROPOROUS AND MESOPOROUS MATERIALS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 226 p. 71 - 78

1387-1811

Pectin was used as nucleation agent in the synthesis of spherical mesoporous Ag3PO4 microspheres forthe development of dual antimicrobial carrier containing a fluoroquinolone. The hybrid Ag3PO4epectinmicrospheres were characterized by biophysical methods using optical, scanning and transmissionelectronic microscopies, X-ray diffraction and energy dispersive analysis, differential scanning calorimetry,laser diffraction, and molecular gas adsorption (BrunauereEmmetteTeller). Scanning electron microscopy(SEM) images of silver phosphate microspheres without pectin displayed heterogeneoussurface, bimodal size distribution between 0.9e1.0 mm and 1.5e1.8 mm with 20% and 25% populationyield respectively and high amount of salt detritus. Meanwhile, SEM microphotographies of silverphosphate microspheres synthesized in presence of pectin showed a drastic change of particlemorphology, homogenous surface, narrow size particle distribution in the 1.3e1.5 mm range with 90%population yield, 20e30% pore size increase and without debris. X-ray diffraction analysis of silverphosphate microspheres showed the same crystal profile in presence or absence of pectin suggesting nochanges in the crystalline structure of Ag3PO4 by the addition of the biopolymer was made. Effect ofsilver phosphate hybrid microspheres loaded with levofloxacin tested against Escherichia coli andStaphylococcus aureus showed strong bactericidal activity compared with the bacteriostatic effect of freelevofloxacin. The results are suggesting that hybrid Ag3PO4epectin microspheres containing levofloxacincan be used as effective antimicrobial against several microorganisms, making them applicable to diversemedical devices and for antimicrobial control systems. The Ag3PO4epectin hybrid microspheres areadvantageous since they are synthesized by green chemistry methodology under standard laboratoryconditions, do not requiring purification steps, the technique is highly reproducible and they are availablefor drug loading and specific target tailoring. The main advantage of Ag3PO4epectin microspheres isthe synergic antimicrobial activity of the silver ion and the antibiotic in the same microdevice acting asbiocide matrix and also as carrier for levofloxacin.