Beckman optima max xp ultracentrifuge

Dissolved TUL and TUL-NPs in the ointments were isolated using centrifugation at 100,000× g (Beckman Optima^TM MAX-XP Ultracentrifuge, Beckman Coulter, Osaka, Japan). Isolated TUL was dissolved using methanol, and the content was measured in order to calculate the solubility of TUL in the ointments. The TUL contents were measured using the HPLC method described below.

Soluble CIL and CIL-NPs in the gels were separated by centrifugation at 100,000× g using a Beckman Optima^TM MAX-XP Ultracentrifuge (Beckman Coulter, Osaka, Japan), and the solubility was determined on the basis of the concentration of soluble-CIL measured via the HPLC method described above. An atomic force microscopy (AFM) image of the CIL-NPs was generated using an SPM-9700 (Shimadzu Corp., Kyoto, Japan), and the particle-size distribution of CIL was measured using both a NANOSIGHT LM10 (QuantumDesign Japan, Tokyo, Japan) and an SALD-7100 (Shimadzu Corp., Kyoto, Japan). In this study, the refractive index used to analyze CIL particles was set at 1.60–0.10i in the SALD-7100. The viscosity of the CIL gel was analyzed using a Brookfield digital viscometer (Brookfield Engineering Laboratories, Inc., Middleboro, MA, USA), and the number of CIL-NPs was measured using the NANOSIGHT LM10. The viscosity in the NANOSIGHT LM10 was set to 1.27 mPa·s. In the evaluation of CIL gels, they were stored in the dark at 20 °C for 30 days, and the size, number, and shape of CIL-NPs were measured according to the above-described procedures.