Consideration of Preventing Local Venous Pain by Dacarbazine

Multifunctional Covalent Organic Framework-Based Microneedle Patch for Melanoma Treatment

Melanoma is resistant to conventional chemotherapy and radiotherapy. Therefore, it is essential to develop a targeted, low-toxic, and minimally invasive treatment. Here, DTIC/ICG-Fe3O4@TpBD BSP/HA microneedles (MNs) were designed and fabricated, which can enhance targeting to melanoma and perform photothermal therapy (PTT) and chemotherapy simultaneously to synergistically exert anticancer effects. The system consisted of magnetic nanoparticles (DTIC/ICG-Fe3O4@TpBD), dissoluble matrix (Bletilla polysaccharide (BSP)/hyaluronic acid (HA)), and a polyvinyl alcohol backing layer. Due to the good magnetic responsiveness of Fe3O4@TpBD, dacarbazine (DTIC) and indocyanine green (ICG) can be better targeted to the tumor tissue and improve the therapeutic effect. BSP and HA have good biocompatibility and transdermal ability, so that the MNs can completely penetrate the tumor tissue, be dissolved by the interstitial fluid, and release DTIC and ICG. Under near-infrared (NIR) light irradiation, ICG converts light energy into thermal energy and induces ablation of B16-OVA melanoma cells. In vivo results showed that DTIC/ICG-Fe3O4@TpBD BSP/HA MNs combined with chemotherapy and PTT could effectively inhibit the growth of melanoma without tumor recurrence or significant weight loss in mice. Therefore, DTIC/ICG-Fe3O4@TpBD BSP/HA MNs are expected to provide new ideas and therapeutic approaches for the clinical treatment of melanoma.

Impact of Light Shielding on Photo-Degradation of Dacarbazine during the Preparation Process

Dacarbazine (DTIC) is converted to the photo-degradation product 4-diazoimidazole-5-carboxamide (Diazo-IC) by light. Diazo-IC production is often responsible for the pain reactions observed during peripheral intravenous infusion of DTIC in clinical settings. Although light shielding during infusion decreases the photo-degradation of DTIC, its usefulness for the preparation of DTIC has not yet been fully clarified. The aim of this study was to investigate the light conditions during the preparation of DTIC solution in the compounding room from the viewpoint of the production amount of Diazo-IC. DTIC solution was prepared in the compounding room. Various light and temperature conditions and dissolving solutions during the preparation were investigated. The amounts of DTIC and Diazo-IC in solutions were determined using an HPLC coupled to UV detection. The photo-degradation of DTIC was estimated by the amount of Diazo-IC. Diazo-IC production in the dissolving solutions increased in a time-dependent manner at 4 and 25°C under light shielding. Light exposure during the dissolving process did not affect the DTIC and Diazo-IC concentrations. Light shielding during dissolution did not alter the Diazo-IC production until 4 h after dilution. In conclusion, short duration light exposure did not affect Diazo-IC production. These findings suggest that light shielding is not needed in the preparation of DTIC in the compounding room from the viewpoint of Diazo-IC production.

Dacarbazine nanoparticle topical delivery system for the treatment of melanoma

Dacarbazine (DZ) is poorly soluble in water with the short half-life in blood circulation, low rate of response with the toxic effect which ultimately limits its utilization of the treatment of skin cancer. In view of this background current study was designed for development of dacarbazine laden nanoparticle (DZNP) and dacarbazine laden nanocream (DZNC) topical delivery system for the treatment of melanoma. Firstly DZNP was prepared. By using DZNP its cream formulation prepared for topic drug delivery for melanoma. Dacarbazine nanoparticle and its cream were evaluated for morphology, drug load capacity, efficiency of nanoencapsulation and size of particle and zeta potential, Transmission Electron Microscopy (TEM), determination of pH, spreadability and viscosity, in vitro drug release capacity and its cytotoxic potential. The particle size of DZNP and DZNC was 16.3 ± 8.1 nm and 16.9 ± 7.8 nm respectively. pH value and spreadability of nanoparticle cream were found to be 6.7 ± 0.14 g cm/sec and 55.23 ± 3.13 g cm/sec respectively. Nanoencapsulation efficiency and Drug loading capacity were 67.4 ± 3.5% and 6.73 mg/10 mg respectively. IC50 of dacarbazine nanoparticle was 0.19 mg/ml while it was 0.63 mg/ml for nanoparticle cream. It can be concluded that DZNP and its cream can be effectively used as a topical formulation for the treatment of melanoma.