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Ion association and hydration clusters in aqueous lithium borate solution are extremely important to understand some extraordinary properties of lithium borates. In the present work, polyborate distribution in aqueous LiBO2 solution was investigated through Raman and thermodynamics equilibrium analysis. Geometry and stability of hydrated clusters LiB(OH)4(H2O)n up to n = 8 were calculated at the B3LYP/aug-cc-pVDZ level. Three different types of ion association, namely, contact ion pairs (CIP), solvent-shared ion pairs (SIP) and solvent separated ion pairs (SSIP) were obtained; characteristics of all of these stable configurations were determined, and the most stable hydrated clusters were chosen. Then the mechanisms of ion aggregation and crystal nuclei formation in the LiB(OH)4 solution were proposed. The tight four-hydrated sphere of Li+ makes it difficult for the dehydrated form of its first hydration sphere to from a CIP, which is the passible reason that lithium borate always has a large super-saturation degree.

Ion association and hydration clusters in aqueous lithium borate solution are extremely important to understand some extraordinary properties of lithium borates. In the present work, polyborate distribution in aqueous LiBO2 solution was investigated through Raman and thermodynamics equilibrium analysis. Geometry and stability of hydrated clusters LiB(OH)4(H2O)n up to n = 8 were calculated at the B3LYP/aug-cc-pVDZ level. Three different types of ion association, namely, contact ion pairs (CIP), solvent-shared ion pairs (SIP) and solvent separated ion pairs (SSIP) were obtained; characteristics of all of these stable configurations were determined, and the most stable hydrated clusters were chosen. Then the mechanisms of ion aggregation and crystal nuclei formation in the LiB(OH)4 solution were proposed. The tight four-hydrated sphere of Li+ makes it difficult for the dehydrated form of its first hydration sphere to from a CIP, which is the passible reason that lithium borate always has a large super-saturation degree.

Utilization of quercetin (QT) in clinics is limited by its instability and poor solubility. To overcome these disadvantages, we prepared QT as QT-loaded PLGA-TPGS nanoparticles (QPTN) and examined its properties and therapeutic efficacy for liver cancer. QT-loaded PLGA nanoparticles (QPN) and QT/coumarin-6-loaded PLGA-TPGS nanoparticles (QCPTN) with coumarin-6 as a fluorescent marker were also prepared to investigate the cellular uptake by HepG2 and HCa-F cells using a confocal laser scanning microscope (CLSM), and their effects on apoptosis of HepG2 cells were assessed with flow cytometry. The results measured using transmission electron microscopy, scanning electron microscopy and size analyses indicated that QPTN were stably dispersed sphere with diameter in the range of 100-200 nm. It indicated that the QT loading and encapsulation efficiency in QPTN reached 21.63% and 93.74%, respectively, and the accumulative drug release of QPTN was 85.8%, the QCPTN uptake in HCa-F and HepG2 cells were 50.87% and 61.09% using HPLC analysis, respectively. The results determined using an Annexin-PI flow cytometry indicated that QPTN could induce HepG2 cell apoptosis in a dose dependent manner. The results of histological examination and HPLC analysis confirmed that QPTN was targeted to liver cells. In vivo analysis using solid tumor-bearing mouse model indicated that QPTN could suppress tumor growth by 59.07%. Moreover, all the studied properties of QPTN were more desirable than those of QT-loaded PLGA nanoparticles (QPN). In conclusion, QPTN could be used as a potential intravenous dosage form for the treatment of liver cancer owing to the enhanced pharmacological effects of QT with increased liver targeting.