Chitosan (CS) nanoparticles have been developed as a versatile drug delivery system to transport drugs, genes, proteins, and peptides into target sites. Demands on fluorescent nanoparticles have increased recently due to various applications in medical and stem-cell-based researches. In this study, fluorescent CS nanoparticles were prepared by a mild method, namely, complex coacervation. Entrapment efficiency of sulforhodamine (SR101) loaded into CS nanoparticles was investigated to evaluate their capacity in incorporating fluorescent molecule. Particle size of produced fluorescent nanoparticles was in the range of 600-700 nm, and their particle size was highly dependent on the CS molecular weight as well as concentration. A high entrapment efficiency of SR101 into CS nanoparticles could also be obtained when it was dissolved in methanol. In conclusion, highly loaded fluorescent CS nanoparticles could be easily prepared using complex coacervation method and therefore can be applied in various medical researches.
Pharmacokinetic-pharmacodynamic (PK-PD) modeling has emerged as a major tool in clinical pharmacology to optimize drug use by designing rational dosage forms and dosage regimes. Quantitative representation of the dose-concentration-response relationship should provide information for the prediction of the level of response to a certain level of drug dose. This paper describes the experimental details of the preformulation study, tablet manufacture, optimization, and bioanalytical methods for the estimation of dexibuprofen in human plasma. The hydrophilic matrix was prepared with xanthen gum with additives Avicel PH 102. The effect of the concentration of the polymer and different filler, on the in vitro drug release, was studied. Various pharmacokinetic parameters including AUC(0-t), AUC(0-∞), C(max), T(max), T(1/2), and elimination rate constant (K(el)) were determined from the plasma concentration of both formulations of test (dexibuprofen 300 mg) and reference (dexibuprofen 300 mg tablets). The merits of PK-PD in the development of dosage forms and how PK-PD model development necessitates the development of new drugs and bio analytical method development and validation are discussed. The objectives of the present study, namely, to develop and validate the methods to estimate the selected drugs in the biological fluids by HPLC, the development of in vitro dissolution methods, and PK-PD model development have been described.