Abstract:bindingratesofdifloxacin(DIF)toplasmaproteinsofandtoinvestigatetheeffectsoftemperature,andoftheconcentrationsofplasmaandthedrug,onthebindingcharacteristics.Thebindingratedecreasedfrom32.4%to19.6%asthedrugconcentrationwasraisedfrom0.5μg/mLto5μg/mLbutwasunchangedbetweendrugconcentrationsof5μg/mLand40μg/mL.Thebindingrateswerenotaffectedbytemperaturesof4,15,20,25,or37,butthebindingrateinundilutedplasmawassignificantlyhigherthanintwofold(8.87±0.39)%andfourfolddilutedplasma()anddissociationconstant(mol/gand4.04×10mol/L,respectively.Theconcentrationofthedissociateddrughadalinearrelationshipwiththetotalconcentrationofthedrugandwasgivenbytheequation:Thus,thebindingrateofDIFtoplasmaproteininisdrugconcentration-dependent;itisnotaffectedbyexperimentaltemperaturesbetween4;itislinearwithconcentrationsofDIFbetween5μg/mLand40μg/mL;anditshowsanonlinearrelationshipbetween0.5μg/mLand5μg/mL.
