Factors Influencing The Sorption Of Ciprofloxacin Lab Analysis
Factors influencing the sorption of ciprofloxacin by sediment samples
The estimated Kd values ranging from 171 to 37347 mL/g indicate a very high sorption of CIP on investigated sediments which corresponding to sorption data of ciprofloxacin (Pereira Leal et al., 2013) and fluoroquinolones in general (Peruchi et al., 2015) but on soil samples. Some of this information might be helpful in judging the sorption of antibiotics such ciprofloxacin onto sediments but potential differences between the soil and sediment should be taken into account. The difference between soil and sediment are in the content of mineral substances and the mechanism of sorption. Sediments have less minerals, and they are occur many hydrophobic-independent mechanisms due …show more content…
Among all tested sediments, sediment 7 is an isolated case so that this theoretical fact cannot be applied to other sediments. Important role in the sorption of CIP for sediments have cation bridging involving the dissociated carboxylic groups of the zwitterion although neither an ion-pairing cannot be excluded. Mentioned mechanisms are supported by the fact that the sorption is higher than the percentages of cations (Pereira Leal et al., 2013) (for example, from 92-99% of the applied CIP was sorbed to all sediment samples whereas only in the case of sediment 7, 96% of these molecules were cationic) and that Kd values (obtained at 25 °C and 0.01 M CaCl2) in most cases were correlated with CEC of the sediments. This statement in accordance with Figueroa-Diva (Figueroa-Diva et al., 2010) and Vasudevan (Vasudevan et al., 2009) which are found that the sorption of fluoroquinolones (CIP is also highlighted among them) was affected mainly by soil CEC. Also, they reported that organic carbon contents show little effect which was unclear. Looking at our results, it was noted that highest content of OM has sediment 6 but in the same time has the smallest Kd values (obtained at 25 °C and 0.01 M …show more content…
So, Pei and co-workers (Pei et al., 2009) found that Cu increases CIP sorption on mineral components kaolinite and montmorillonite in a certain pH range, but Ross and Riley (Ross and Riley, 1992) showed that Cu increases the mobility and solubility of fluoroquinolones (Chen et al., 2013). Although sediments 5 and 6 have the highest concentration of certain affordable microelements (Cu, Fe, Zn and Mn) show the lowest sorption potential to CIP, this contribution to sorption of CIP cannot be ignored. On the other hand, it is a re-confirmation of the complexity of the pharmaceuticals sorption in sediments, or to every other sediments need to special approach.
Ionic strength is also important adsorbing component of sediments. The influence of initial CIP concentration and ionic strength in equilibrium sorption of CIP by sediments at 25 °C are presented in Figure 3.
Figure
The estimated Kd values ranging from 171 to 37347 mL/g indicate a very high sorption of CIP on investigated sediments which corresponding to sorption data of ciprofloxacin (Pereira Leal et al., 2013) and fluoroquinolones in general (Peruchi et al., 2015) but on soil samples. Some of this information might be helpful in judging the sorption of antibiotics such ciprofloxacin onto sediments but potential differences between the soil and sediment should be taken into account. The difference between soil and sediment are in the content of mineral substances and the mechanism of sorption. Sediments have less minerals, and they are occur many hydrophobic-independent mechanisms due …show more content…
Among all tested sediments, sediment 7 is an isolated case so that this theoretical fact cannot be applied to other sediments. Important role in the sorption of CIP for sediments have cation bridging involving the dissociated carboxylic groups of the zwitterion although neither an ion-pairing cannot be excluded. Mentioned mechanisms are supported by the fact that the sorption is higher than the percentages of cations (Pereira Leal et al., 2013) (for example, from 92-99% of the applied CIP was sorbed to all sediment samples whereas only in the case of sediment 7, 96% of these molecules were cationic) and that Kd values (obtained at 25 °C and 0.01 M CaCl2) in most cases were correlated with CEC of the sediments. This statement in accordance with Figueroa-Diva (Figueroa-Diva et al., 2010) and Vasudevan (Vasudevan et al., 2009) which are found that the sorption of fluoroquinolones (CIP is also highlighted among them) was affected mainly by soil CEC. Also, they reported that organic carbon contents show little effect which was unclear. Looking at our results, it was noted that highest content of OM has sediment 6 but in the same time has the smallest Kd values (obtained at 25 °C and 0.01 M …show more content…
So, Pei and co-workers (Pei et al., 2009) found that Cu increases CIP sorption on mineral components kaolinite and montmorillonite in a certain pH range, but Ross and Riley (Ross and Riley, 1992) showed that Cu increases the mobility and solubility of fluoroquinolones (Chen et al., 2013). Although sediments 5 and 6 have the highest concentration of certain affordable microelements (Cu, Fe, Zn and Mn) show the lowest sorption potential to CIP, this contribution to sorption of CIP cannot be ignored. On the other hand, it is a re-confirmation of the complexity of the pharmaceuticals sorption in sediments, or to every other sediments need to special approach.
Ionic strength is also important adsorbing component of sediments. The influence of initial CIP concentration and ionic strength in equilibrium sorption of CIP by sediments at 25 °C are presented in Figure 3.
Figure