Characterization of Celecoxib-Loaded Solid Lipid Nanoparticles Formulated with Tristearin and Softisan 100

Purpose: To prepare solid lipid nanoparticles employing softisan 100 (SOFTI) or tristearin (TS) as solid lipid carriers for celecoxib (CXB) to overcome its dissolution challenge.Methods: The solid lipid nanoparticles (SLN) of CXB were prepared by ultrasonic melt-emulsification technique. SLN was characterized using differential scanning calorimetry (DSC), Fourier transform infra spectroscopy (FTIR), as well as for entrapment efficiency, particle size, zeta potential and CXB release.Results: The SLN formulations exhibited high CXB entrapment efficiency (91.6 % for SOFTI and 94.6 % for TS) while mean particle size was 181.0 ± 4.6 and 346.3 ± 3.8 nm for SOFTI and TS, respectively. The DSC thermograms showed the disappearance of CXB peak due to its molecular distribution in the lipid nanoparticles while FTIR spectra revealed physical interaction of CXB with the tested lipids. The tendency of SOFTI to liberate CXB in 24 h was higher than that of TS (55.5 ± 1.07 vs 49.2 ± 2.94 %, p < 0.05). Drug release was by non-Fickian mechanism.Conclusion: Formulation of CXB in SLN using TS or SOFTI produces sustained drug release delivery that can overcome the dissolution limitation of the drug and thus, improve its therapeutic efficacy.Keywords: Celecoxib, Solid lipid nanoparticles, Tristearin, Softisan, Dissolution limitation, Sustained drug releas

Evaluation of Ionotropic Cross-Linked Chitosan/Gelatin B Microspheres of Tramadol Hydrochloride

Microspheres of tramadol hydrochloride (TM) for oral delivery were prepared by complex coacervation method without the use of chemical cross-linking agents such as glutaraldehyde to avoid the toxic reactions and other undesirable effects of the chemical cross-linking agents. Alternatively, ionotropic gelation was employed by using sodium-tripolyphosphate as cross-linking agent. Chitosan and gelatin B were used as polymer and copolymer, respectively. All the prepared microspheres were subjected to various physicochemical studies, such as drug–polymer compatibility by thin layer chromatography (TLC) and Fourier transform infrared (FTIR) spectroscopy, surface morphology by scanning electron microscopy, frequency distribution, drug entrapment efficiency, in vitro drug release characteristics and release kinetics. The physical state of drug in the microspheres was determined by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). TLC and FTIR studies indicated no drug–polymer incompatibility. All the microspheres showed initial burst release followed by a fickian diffusion mechanism. DSC and XRD analysis indicated that the TM trapped in the microspheres existed in an amorphous or disordered-crystalline status in the polymer matrix. From the preliminary trials, it was observed that it may be possible to formulate TM microspheres by using biodegradable natural polymers such as chitosan and gelatin B to overcome the drawbacks of TM and to increase the patient compliance