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Introduction: The objective of the present investigation was to develop a multiparticulate modified release system of methylphenidate hydrochloride (HCl) generating biphasic release profile from single core. Materials and Methods: Wurster (bottom spray fluid bed coating) process was employed to develop extended release (ER) pellets of methylphenidate HCl. Impact of various formulation variables was assessed using statistical interpretation such as analysis of variance. A 3 2 (two factor, three level) factorial design was employed to study the effect of independent variables (ER polymer [Eudragit RSPO/ Eudragit RLPO/Ethocel] concentration and plasticizer concentration), on dependent variables (drug release at 3 rd and 8 th h). Optimization was done by fitting experimental data to the software program (Design Expert). The design space for formulation variables (ER polymer concentration and plasticizer concentration) and its influence on drug release was developed. Results and Discussion: Fabricated pellets were characterized for various physicochemical parameters. In vitro release data observed from the optimized formulation was fitted into various kinetic equations. The optimized formulation showed desired drug release at both 3 rd and 8 th h as 60.33% ± 0.58% and 93.33% ± 0.58%, respectively. Capsules showed an initial burst release preceding a more gradual ER phase following first order kinetics and Fickian diffusion process. Conclusion: Methylphenidate HCl ER pellets were successfully developed by employing bottom spray fluid bed coating (Wurster) technique. The factorial experimental design facilitated the formulation and optimization of modified drug delivery system of methylphenidate HCl.

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N ebivolol hydrochloride is unique antihypertensive drug, which gets completely absorbed upon oral administration, with t max 1.5-4 h. The poor aqueous solubility leads to slow rate of absorption. An attempt has been made to enhance dissolution of nebivolol (NB) using solid dispersion (SD) and SD adsorbate (SDA) techniques. Various hydrophilic excipients such as polyethylene glycol 6000 (PEG), gelucire 50/13 (GL), and neusilin US2 (NUS) at different ratios were used. The prepared SDA of NB was characterized for % drug yield and other physical characteristics and in vitro drug dissolution studies in 0.1N HCl (pH 1.2). The formulation optimized on the basis of in vitro drug dissolution and % drug content was also characterized by the Fourier transform infrared (FTIR) spectroscopy; differential scanning calorimetry (DSC), X-ray powder diffractometry analysis (XRD). The FTIR study indicated no interaction between the drug and polymer. DSC thermograms showed the significant change in melting peak of the NB when prepared as SDA suggesting the change in crystallinity of NB. The data from the XRD showed that the drug was still detectable in its solid state in the SDA of PEG and disappeared in case of higher ratio of GL. An increased dissolution rate of NB at pH 1.2 was observed when the drug was dispersed in these carriers in the form of physical mixtures (PMs), SDs by solvent evaporation methods (SMs), SDs by fusion method and SDAs by fusion method. NB released faster from the SDAs than from the pure crystalline drug, the PMs, the SMs, or the SDs. Thus, this study was proved as a promising approach for the improvement of dissolution rate and solubility of NB.