Encapsulating systems prepared with beta-lactoglobulin, the major component of whey protein, may serve as versatile bioavailability enhancers for poorly absorbed nutraceuticals.

BackgroundA multi-drug delivery platform is needed as the intra-tumoral heterogeneity of cancer leads to different drug susceptibility. Cancer stem cells (CSCs), a small population of tumor cells responsible for tumor seeding and recurrence, are considered chemotherapy-resistant and have been reported to be sensitive to salinomycin (Sal) instead of paclitaxel (Ptx). Here we report a novel silk fibroin (SF) hydrogel-loading Sal and Ptx by incorporating drug-loaded silk fibroin nanoparticles (SF-NPs) to simultaneously kill CSCs and non-CSCs.MethodsUsing the method we have previously reported to prepare Ptx-loaded SF-NPs (Ptx-SF-NPs), Sal-loaded SF-NPs (Sal-SF-NPs) were fabricated under mild and non-toxic conditions. The drug-loaded SF-NPs were dispersed in the ultrasound processed SF solution prior to gelation.ResultsThe resulting SF hydrogel (Sal-Ptx-NP-Gel) retained its injectable properties, exhibited bio-degradability and demonstrated homogeneous drug distribution compared to the non-NP incorporated hydrogel. Sal-Ptx-NP-Gel showed superior inhibition of tumor growth compared to single drug-loaded hydrogel and systemic dual drug administration in the murine hepatic carcinoma H22 subcutaneous tumor model. Sal-Ptx-NP-Gel also significantly reduced CD44+CD133+ tumor cells and demonstrated the least tumor formation in the in vivo tumor seeding experiment, indicating superior inhibition of cancer stem cells.ConclusionThese results suggest that SF-NPs incorporated SF hydrogel is a promising drug delivery platform, and Sal-Ptx-NP-Gel could be a novel and powerful locoregional tumor treatment regimen in the future.

We propose a bidirectional tunable optical diode based on a periodically poled lithium niobate (PPLN) with defect. An acoustic wave propagates together with the light beam so that a collinear photon-phonon interaction happens, which affects the nonlinear optical processes in PPLN. The fundamental wave exhibits an optical diode effect, i.e., the light only may travel toward a single direction while the opposite way is isolated. However, the acoustic wave could be used to adjust the contrast of optical isolation from -1 to 1. A direction-optional operation is thus realized. Moreover, the advantages of our tunable PPLN optical diode are also discussed.