A nanosystem loaded with perfluorohexane and rose bengal coupled upconversion nanoparticles for multimodal imaging and synergetic chemo-photodynamic therapy of cancer.

Theranostics is a new trend integrating diagnostic and therapeutic functions in tumour research. Theranostic nanoparticles enabling both tumour imaging and drug delivery are a promising platform for image-guided cancer therapy. Photodynamic therapy (PDT) has great potential in synergy with traditional chemotherapy but faces great challenges due to hypoxia, poor targeting ability and the limited penetration depth of visible light. To solve these problems, we presented a novel nanosystem of FA/UCNPs-RB/HCPT/PFH@lipid (denoted as FURH-PFH-NPs), with a perfluorohexane (PFH) carrying rich oxygen core and a folic acid-modified lipid shell. The shell contains 10-hydroxycamptothecin (HCPT) and self-fluorescing photosensitizer compounds, namely, upconversion nanoparticles and rose bengal (UCNPs-RB). In this study, FURH-PFH-NPs aggregated in SKOV3 cells (in vitro) and the nude xenograft tumour region when combined with folic acid receptors. When triggered by low-intensity focused ultrasound (LIFU), FURH-PFH-NPs released PFH, UCNPs-RB and HCPT. The above procedure was monitored through multimodal imaging, which simultaneously guided the tumour therapy. UCNPs-RB and PFH promoted the PDT effect under LIFU. Through PDT and HCPT, we obtained better therapeutic effects and good biosafety against SKOV3 nude xenograft tumours. FURH-PFH-NPs combined with LIFU and laser irradiation might be a promising strategy for ovarian cancer.

[Determination of chrysosplenetin, metabolic inhibitor of artemisinin, in rat plasma by UPLC-ms/MS and study on its pharmacokinetics].

OBJECTIVE: The study aimed to develop the assay of chrysosplenetin (CHR), a metabolic inhibitor of artemisinin by UPLC-MS/MS in rat plasma and investigate the pharmacokinetics parameters of CHR. METHOD: The plasma samples were precipitated by acetonitrile to remove the proteins. Separation was carried out on a Shim-pack XR-ODS C,18(2. 0 mm x 100 mm, 2. 2 micromp.m) column using a mobile phase containing methanol-0. 1% formic acid (87:13) using by diazepam as internal standard. Mass spectrometer with electrospray ionization (ESI) operated in the positive ion mode was used for analysis. Total analysis time was 2 min. RESULT: The assay was linear in the range 5-5 000 microg L-1 (r =0. 999 3) with recoveries in the range from 69. 0% to 81.2% and satisfied inter-, intra- precision and accuracy. CHR after oral administration is not easy to absorb with double or multimodal peak phenomenon. The t1/2 of CHR after intravenous injection was very short and that of low, medium, and high dosage was (17. 01 +/- 8. 06) , (24. 62 +/- 4. 59), (28. 46+/- 4. 63) min, respectively. CONCLUSION: The developed method was special, rapid, and sensitive for determination of CHR pharmacokinetics. [Key words] UPLC-MS/MS; chrysosplenetin; pharmacokinetics; plasma; rat