Enhanced Stability of the Pharmacologically Active Lactone Form of 10-Hydroxycamptothecin by Self-Microemulsifying Drug Delivery Systems

Advances in Antitumor Nano-Drug Delivery Systems of 10-Hydroxycamptothecin

10-Hydroxycamptothecin (HCPT) is a natural plant alkaloid from Camptotheca that shows potent antitumor activity by targeting intracellular topoisomerase I. However, factors such as instability of the lactone ring and insolubility in water have limited the clinical application of this drug. In recent years, unprecedented advances in biomedical nanotechnology have facilitated the development of nano drug delivery systems. It has been found that nanomedicine can significantly improve the stability and water solubility of HCPT. NanoMedicines with different diagnostic and therapeutic functions have been developed to significantly improve the anticancer effect of HCPT. In this paper, we collected reports on HCPT nanomedicines against tumors in the past decade. Based on current research advances, we dissected the current status and limitations of HCPT nanomedicines development and looked forward to future research directions.

Fluocinolone Acetonide Microemulsion in Combination with a Fractional Laser for the Treatment of Scalp Psoriasis

This study introduces fluocinolone acetonide (FA) microemulsion in combination with ablative fractional lasering as a new effective treatment for scalp psoriasis. A pseudo-ternary phase diagram was constructed using the aqueous titration method. The suitable ratio of surfactant mixture (S_mix):oil mixture (O_mix):water was chosen from the microemulsion region of the diagram. FA was loaded into the selected ratio to prepare FA microemulsion. Ex vivo skin permeation study of the FA microemulsion with fractional laser assistance was performed to determine a proper ablative depth. A pilot clinical study was conducted to evaluate the efficacy of FA microemulsion and FA microemulsion combination with lasering at the optimum ablation depth. The selected microemulsion base contained (in wt%) 77% water, 20% S_mix (Tween 80:ethanol, 2:1), 3% O_mix (10% benzyl benzoate and 1% benzyl alcohol in bergamot oil), and 0.2% sodium carboxymethylcellulose. FA was loaded into this base at a concentration of 0.1%. The skin lasered at an ablation depth of 50 µm was conducted in the pilot clinical study. Scalp psoriasis responded well to the FA microemulsion. Psoriasis scalp severity index (PSSI) scores indicated that the FA microemulsion plus laser treatment provides higher efficacy than the FA microemulsion alone without any topical and systemic side effects. The efficacy of the treatments could be maintained for at least 1 week after treatment discontinuation. FA microemulsion was properly formulated and evaluated. The microemulsion demonstrating the greatest benefits was used in combination with ablative fractional lasering to treat scalp psoriasis.

Development of Self-Microemulsifying Drug Delivery System to Improve Nisoldipine Bioavailability: Cell Line and In Vivo Evaluations : Development of Self-Microemulsifying Drug Delivery System

The authors attempted to fabricate a novel lipid-based formulation of a lipophilic drug, nisoldipine (NISO). As NISO belongs to BCS class 2 drug, it suffers from low bioavailability (5%). Hence, the research was intended to ameliorate oral bioavailability of NISO via intestinal lymphatic transport. The NISO loaded self microemulsifying drug delivery system (SMEDDS) (NISO SMEDDS) was prepared using Peceol, Cremophor EL, and Transcutol HP. The Cremophor EL and Transcutol HP at 1:1 ratio showed maximum microemulsifying area, and average globule size was 16.78 ± 0.97 nm with PDI 0.121 ± 0.024. Cellular uptake studies (confocal microscopy and flow cytometry) using Caco-2 cells depicted higher fluorescence with coumarin-6 loaded SMEDDS as that of coumarin-6 solution which indicated deeper penetration. Mean fluorescence intensity (MFI) of coumarin-6 loaded SMEDDS was significantly improved (9.92-fold) in contrast to coumarin-6 solution. The NISO SMEDDS showed enhanced permeability (5.02 times) across Caco-2 cells compared to NISO suspension. The bioavailability improvement with NISO SMEEDS was 2.14 times relative to suspension, and lymphatic uptake was involved in oral absorption of NISO SMEDDS.