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61.
Graphene nanoribbons are thin sheets of graphene showing exclusive characteristics such as better drug-loading capacity, adsorption on mammalian cells, greater surface area, and light-absorbing ability. The current research work is to develop metformin-adsorbed carboxyl-functionalized oxidized graphene nanoribbons and utilize drug repurposing for the treatment of oral cancer by activating photo-thermal radiation therapy. The nanoribbons are formulated by Hummer's method and evaluated for several characterization parameters like ATR- Fourier Transform Infrared (FTIR), Differential scanning calorimetry (DSC), topology, in vitro efficacy, ex vivo and in vitro cell line studies. The ATR-FTIR spectrum of formulated nanoribbons shows distinctive peak at 3370 cm−1 ( N H group) of metformin. The DSC specifies the incidence of steep endothermic crests at 235 °C ( C NH3). The in vitro and ex vivo drug release studies show enhanced drug release in acidic pH (6.4) than physiological pH (7.4) with photothermal radiation. The in vitro cell line studies are processed via two-way ANOVA that exhibits 67.74 ± 0.03% of % inhibition in presence of photothermal radiation. The study demonstrates higher inhibition of cancerous cells at lower concentration of drug and photothermal therapy in comparison to plain drug. The characteristic feature of graphene is used to develop targeted drug delivery system against the oral cancerous cells. 相似文献
62.
A quantitative method has been developed and validated for the determination of 2-arachidonoylglycerol (2-AG) in hairless guinea pig plasma by liquid chromatographic-electrospray ionization mass spectrometry. The analytes were extracted from the plasma samples of guinea pig by a single step liquid extraction technique using acetonitrile. The chromatographic separation was conducted on a C18 column using a gradient mobile phase consisting of methanol and water at a flow rate of 0.3 mL min?1. The analytes were quantified by positive electrospray ionization mass spectrometry with selected ion monitoring mode of m/z 401. The limit of detection for 2-AG was 0.5 ng mL?1. This method required only simple processing of the samples to prevent the isomerization of 2-AG during sampling and handling and could be applied to determine the plasma concentration profiles in hairless guinea pigs. The volume of distribution at steady state (V ss), total plasma clearance (CL) and half life (t 1/2β) of 2-AG in hairless guinea pigs were 0.21 ± 0.025 L kg?1, 9.2 ± 1.5 L h?1 kg?1, and 17.7 ± 3.8 min, respectively. 相似文献
63.
Werner S Iyer PS Fodor MD Coleman CM Twining LA Mitasev B Brummond KM 《Journal of combinatorial chemistry》2006,8(3):368-380
The solution-phase synthesis of a discovery library of 178 tricyclic pyrrole-2-carboxamides was accomplished in nine steps and seven purifications starting with three benzoyl-protected amino acid methyl esters. Further diversity was introduced by two glyoxaldehydes and 41 primary amines. The combination of Pauson-Khand, Stetter, and microwave-assisted Paal-Knorr reactions was applied as a key sequence. The discovery library was designed with the help of QikProp 2.1, and physicochemical data are presented for all pyrroles. Library members were synthesized and purified in parallel and analyzed by LC/MS. Selected compounds were fully characterized. 相似文献
64.
65.
The design and facile synthesis of a novel chiral six-membered PNA analogue (2S,5R )-1-(N-Boc-aminoethyl)-5-(thymin-1-yl)pipecolic acid, aepipPNA, that upon incorporation into PNA sequences effected stabilization of complexes with target complementary DNA. This is the first example where a six membered-PNA is shown to be capable of forming stable complexes with DNA and further expands the repertoire of cyclic PNA analogues. 相似文献
66.
Pravin C. Patil Dinesh S. Bhalerao Prasad S. Dangate Krishnacharya G. Akamanchi 《Tetrahedron letters》2009,50(42):5820-5822
Thioamides undergo oxidative dimerization on treatment with hypervalent iodine(V)-containing reagents, particularly o-iodoxybenzoic acid (IBX), in the presence of tetraethylammonium bromide (TEAB) to generate 3,5-disubstituted 1,2,4-thiadiazoles in excellent yield. 相似文献
67.
The limitations and factors affecting the hydride reduction of pyrrolo [1,4]benzodiazepine-5,10-diones to anthramycin-type analogs have been explored. 相似文献
68.
Pottabathula Srinivas Pravin R. Likhar Balsubramanian Sridhar Suresh Bhargava 《Journal of organometallic chemistry》2011,696(3):795-801
The synthesis and structure of palladium(II) complexes bearing uridato/pyridyl ligands as an anionic N-donor coordination sites are reported. The complexes have been shown to be highly active catalysts for the Heck reaction of aryl bromides (TON 4.0×104-9.1×104) and moderate activity for the activation of aryl chlorides under phosphine-free conditions. 相似文献
69.
An analysis is carried out to study the momentum, mass and heat transfer characteristics on the flow of visco-elastic fluid (Walter's liquid-B model) past a stretching sheet in the presence of a transverse magnetic field.In heat transfer, two cases are considered:
- 1.
- The sheet with prescribed surface temperature (PST case); and
- 2.
- The sheet with prescribed wall heat flux (PHF case).
70.
Paudel MK Putalun W Sritularak B Morinaga O Shoyama Y Tanaka H Morimoto S 《Analytica chimica acta》2011,(2):189-193
A colloidal gold conjugated anti-baicalin monoclonal antibody (anti-BA MAb) was prepared and used in an immunochromatographic assay (ICA) for BA in Scutellariae Radix and Kampo medicines. This competitive ICA uses an anti-BA MAb which shows a high specificity for BA and baicalein. Its advantages include a short assay time (15 min), no dependence on any instrumental systems, and it can detect BA in plant materials and Kampo medicines. The limit of detection for the ICA was found to be around 0.6 μg mL−1of baicalin. Moreover, the usefulness of the combination of indirect competitive ELISA and the ICA using anti-BA MAb as a quality control method was confirmed for analysis of BA in Scutellariae Radix and Kampo medicines with a sufficient sensitivity (200 ng mL−1 to 2 μg mL−1), obtainable in an easy and timely manner. 相似文献