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Ovarian cancer remains a challenge to decrease mortality and improve diagnostic efficiency in gynecological cancers. To develop a delivery system capable of efficient cancer cell targeting and delivering novel efficacious therapeutics, we assembled folic acid (FA) conjugated ultrafine iron oxide nanoparticles (uIONP) with encapsulation of DNA topoisomerase inhibitor SN38, which target ovarian cancer cells with over-expression of folate receptor alpha (FRα) and deliver SN38 to induce apoptosis. The assembled FA-uIONP-SN38 exhibited higher drug loading efficiency than the larger counterparts with core diameters more than 10 nm. The targeting specificity of FA-uIONP-SN38 for SKOV-3 cancer cells was validated, with HEK293 kidney cells and Raw264.7 macrophages as non-targeted cell line control. It was found that more SKOV-3 cancer cells were killed due to apoptosis by FA-uIONP-SN38 at the same SN38 dosages compared with uIONP-SN38 and free SN38, respectively. The delivery of this inhibitor to SKOV-3 cancer cells by FRα-targeted FA-uIONP carrier was enhanced by about 10-folds with less cytotoxicity comparing to the free drug SN38. The developed FA-uIONP-SN38 holds a great potential as a theranostic approach in treating ovarian cancer.

Background Pancreatic cancer remains one of the most lethal cancers largely due to the inefficient delivery of therapeutics. Nanomaterials have been extensively investigated as drug delivery platforms, showing improved drug pharmacodynamics and pharmacokinetics. However, their applications in pancreatic cancer have not yet been successful due to limited tumor delivery caused by dense tumor stroma and distorted tumor vasculatures. Meanwhile, smaller-sized nanomaterials have shown improved tumor delivery and retention in various tumors, including pancreatic tumors, suggesting their potential in enhancing drug delivery. Methods An ultrafine iron oxide nanoparticle (uIONP) was used to encapsulate 7-ethyl-10-hydroxyl camptothecin (SN38), the water-insoluble active metabolite of chemotherapy drug irinotecan for treating pancreatic cancer in clinic. Insulin-like growth factor 1 (IGF-1) was conjugated to uIONP as a ligand for targeting pancreatic cancer and stromal cells overexpressing IGF-1 receptor (IGF1R). The SN38 loading and release profile were characterized. The cancer cell targeting and induced apoptosis by developed nano-formulationIGF1-uIONP/SN38 were also investigated. Results IGF1-uIONP/SN38 demonstrated stable drug loading in physiological pH with the loading efficiency of 68.2 ± 3.5% (SN38/Fe, wt%) and

Pancreatic cancer remains one of the most lethal cancers largely due to the inefficient delivery of therapeutics. Nanomaterials have been extensively investigated as drug delivery platforms, showing improved drug pharmacodynamics and pharmacokinetics. However, their applications in pancreatic cancer have not yet been successful due to limited tumor delivery caused by dense tumor stroma and distorted tumor vasculatures. Meanwhile, smaller-sized nanomaterials have shown improved tumor delivery and retention in various tumors, including pancreatic tumors, suggesting their potential in enhancing drug delivery. An ultrafine iron oxide nanoparticle (uIONP) was used to encapsulate 7-ethyl-10-hydroxyl camptothecin (SN38), the water-insoluble active metabolite of pancreatic cancer chemotherapy drug irinotecan. Insulin-like growth factor 1 (IGF-1) was conjugated to uIONP as a ligand for targeting pancreatic cancer cells overexpressing IGF-1 receptor (IGF1R). The SN38 loading and release profile were characterized. The pancreatic cancer cell targeting using IGF1-uIONP/SN38 and subsequently induced cell apoptosis were also investigated. IGF1-uIONP/SN38 demonstrated a stable drug loading in physiological pH with the loading efficiency of 68.2 ± 3.5% (SN38/Fe, wt%) and 7% release for 24 h. In tumor-interstitial- and lysosomal-mimicking pH (6.5 and 5.5), 52.2 and 91.3% of encapsulated SN38 were released over 24 h. The IGF1-uIONP/SN38 exhibited specific receptor-mediated cell targeting and cytotoxicity Ato MiaPaCa-2 and Panc02 pancreatic cancer cells with IC50 of 11.8 ± 2.3 and 20.8 ± 3.5 nM, respectively, but not to HEK293 human embryonic kidney cells. IGF1-uIONP significantly improved the targeted SN38 delivery to pancreatic cancer cells, holding the potential for in vivo theranostic applications.

A directed study for the undergraduate physical chemistry laboratory for determining the transference number of H+(aq) using a modified moving boundary method is presented. The laboratory study combines Faraday’s laws of electrolysis with mole ratios and the perfect gas equation. The volume of hydrogen gas produced at the cathode is monitored and the perfect gas equation is applied to determine the amount of H2(g) produced. The transference number of H+(aq) is then determined from the volume of HCl(aq) swept by the boundary, the molarity of HCl(aq), and the amount of H2(g) produced. The cell is directly powered by 9 V batteries and involves no electronic circuit or a milliammeter. Preparation of the electrochemical cell, experimental procedure, and results of the experiment are presented.