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Non-small cell lung cancer is a major sub-type of lung cancer that is associated with a poor diagnosis resulting in poor therapy for the disorder. In order to achieve a better prognosis, innovative multi-functional systems need to be developed which will aide in diagnosis as well as therapy for the disorder. One such multi-functional delivery system fabricated is Quantum Dots (QDs). QDs are photo-luminescent inorganic nanoparticles utilized for tumor detection, preclinically. Erlotinib hydrochloride, a tyrosine kinase inhibitor, is a first-generation drug developed to treat NSCLC. Its active metabolite, Desmethyl Erlotinib (OSI-420), exhibits similar anticancer activity as erlotinib. OSI-420 was conjugated to QDs to fabricate a delivery system and was then characterized by FT-IR, H NMR, UV-VIS, particle size, zeta potential, fluorescence spectroscopy and TEM. Drug loading was estimated using UV-VIS spectroscopy (52.2 ± 7.5%). A concentration-dependent release of OSI-420 was achieved using esterase enzymes, which was further confirmed using LC-MS. A cellular uptake study revealed the internalization potential of QDs and QD-OSI 420. A cellular recovery study was performed to confirm the internalization potential. Cell viability studies revealed that QD-OSI 420 conjugates had significantly better efficacy than pure drugs in all tested cell lines. QD conjugated OSI-420 demonstrated an IC60 of 2.5 μM in erlotinib-resistant A549 cell lines, where erlotinib or OSI-420 alone could not exhibit 60% inhibition when evaluated up to 20 μM. Similar cytotoxic enhancement of erlotinib was seen with QD-OSI 420 in other NSCLC cell lines as well. These results were strengthened by 3D-SCC model of A549 which revealed that QD-OSI 420 was significantly better in reducing in-vitro 3D tumor volume, as compared to pure drugs. This study, being one of its kind, explores the feasibility of conjugating OSI-420 with QDs as an alternative to traditional anti-cancer therapy, by improving intracellular drug delivery.

The CH 2 Cl 2 /MeOH (1:1) extract of the stem bark of Millettia oblata ssp. teitensis showed antiplasmodial activity (IC 50 = 10–12 μg/mL) against the chloroquine-sensitive (D6) and chloroquine-resistant (W2) strains of Plasmodium falciparum . Chromatographic separation of the extract led to the isolation of a new isoflavone, 4′-prenyloxyderrone ( 1 ), together with known isoflavones (8- O -methylretusin, durmillone, maximaisoflavone B, maximaisoflavone H and maximaisoflavone J), a rotenoid (tephrosin) and a triterpene (lupeol). Similar investigation of Millettia leucantha resulted in the identification of the isoflavones afrormosin and wistin, and the flavone chrysin. The identification of these compounds was based on their spectroscopic data. Five of the isoflavones isolated from these plants as well as 11 previously reported compounds from Millettia dura were tested and showed good to moderate antiplasmodial activities (IC 50 = 13–53 μM), with the new compound, 4′-prenyloxyderrone, being the most active (IC 50 = 13–15 μM).