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In this work, novel theranostic platforms based on graphene oxide and AuNP core polyaniline shell (GO-Au@PANI) nanocomposites are fabricated for simultaneous SERS imaging and chemo-photothermal therapy. PANI, a new NIR photothermal therapy agent with strong NIR absorption, outstanding stability and low cytotoxicity is decorated on AuNPs by one-pot oxidative polymerization, then the Au@PANI core-shell nanoparticles are attached to the graphene oxide (GO) sheet via π-π stacking and electrostatic interaction. The obtained GO-Au@PANI nanohybirds exhibit excellent NIR photothermal transduction efficiency and ultrahigh drug-loading capacity. The nanocomposites can also serve as novel NIR SERS probes utilizing the intense SERS signals of PANI. Rapid SERS imaging of cancer cells is achieved using this ultrasensitive nanoprobe. GO-Au@PANI also reveals good capability of drug delivery with the DOX-loading efficiency of 189.2% and sensitive NIR/pH-responsive DOX release. The intracellular real-time drug release dynamics from the nanocomposites is monitored by SERS-fluorescence dual mode imaging. Finally, chemo-photothermal ablation of cancer cells is carried out in vitro and in vivo using GO-Au@PANI as high-performance chemo-photothermal therapeutic nanoagent. The theranostic applications of GO-Au@PANI endow it with great potential for personalized and precise cancer medicine.

Current therapies for treating malignant glioma exhibit low therapeutic efficiency because of strong systemic side effects and poor transport across the blood brain barrier (BBB). Herein, we combined targeted chemo-photothermal glioma therapy with a novel multifunctional drug delivery system to overcome these issues. Drug carrier transferrin-conjugated PEGylated nanoscale graphene oxide (TPG) was successfully synthesized and characterized. When loaded on the proposed TPG-based drug delivery (TPGD) system, the anticancer drug doxorubicin could pass through the BBB and improve drug accumulation both in vitro and in vivo. TPGD was found to perform dual functions in chemotherapy and photothermal therapy. Targeted TPGD combination therapy showed higher rates of glioma cell death and prolonged survival of glioma-bearing rats compared with single doxorubicin or PGD therapy. In conclusion, we developed a potential nanoscale drug delivery system for combined therapy of glioma that can effectively decrease side effects and improve therapeutic effects.

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Confocal micro-Raman spectroscopy is employed to characterize various grades of human cataracts. Results show that the intensity ratio of the tyrosine doublet (I855/I833) changes from 1:1.07 ± 0.03 to 1:1.17 ± 0.05 with the aggravation of cataracts, which indicates that there are more tyrosine residues bound to strong H acceptors instead of bounding to water. The decrease of relative intensity at 880 cm−1 band suggests that the “buried” tryptophan residues become “exposed” during the course of lens opacification. A three-dimensional principal component analysis is used to classify the Raman spectra of opacity tissues, which show a one-to-one correspondence with different grades of cataracts.

The rapid development of near-infrared surface-enhanced Raman scattering (NIR SERS) imaging technology has attracted strong interest from scientists and clinicians due to its narrow spectral bandwidth, low background interference, and deep imaging depth. In this report, the graphene oxide (GO)-wrapped gold nanorods (GO@GNRs) were developed as a smart and robust nanoplatform for ultrafast NIR SERS bioimaging. The fabricated GO@ GNRs could efficiently load various NIR probes, and the in vitro evaluation indicated that the nanoplatform could exhibit a higher NIR SERS activity in comparison with traditional gold nanostructures. The GOs were prepared by directly pyrolyzing citric acid for greater convenience, and GO@GNRs were fabricated via a facile synthesis strategy. Higher NIR SERS activity, facile synthesis method, excellent biocompatibility, and superb stability make the GO@GNRs/probe complex promising nanoprobes for NIR SERS-based bioimaging applications.

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The main objective of matrix acidizing is to create deep channels(wormholes) that bypass the damaged zone around the wellbore, which eventually, will increase the productivity or injectivity of the well. HCl-diesel emulsified acid is used to achieve that goal as well as other objectives such as prevention of tubing corrosion. The cost of HCl-emulsified acid could be lower by reducing the cost of either the surfactant (emulsifier) or the continuous phase (diesel). Hence, in this study, a low-cost, more efficient emulsified acid is proposed, with cheaper solid stabilizer (nanoparticle) instead of surfactant, and less expensive continuous phase; waste oil instead of diesel. Rheology, stability and coreflooding experiments were performed at high-pressure high-temperature (HPHT) of a typical reservoir conditions in the Middle East. This study addresses the feasibility of a novel waste oil emulsified acid system in acid stimulation treatment. In particular, rheology and stability of the emulsion and reactivity with limestone reservoir rock at HPHT were investigated. The reactivity was carried out through a series of core flow experiments at HPHT and compared with the conventional diesel emulsified acid. Stability experiments were conducted at 375 °F. Coreflood experiments were conducted using Indiana limestone 12″ cores and 1.5 in diameter. The initial permeability of the cores was in the range of 2-4 md. The pressure and temperature were 3000 psi and 275 °F, respectively. Four injection rates were used 0.5, 2, 5, and 10 ml/min. For better comprehension for resulted wormhole characteristic from both stimulation fluids under investigation, the CT-scan image for the Indiana limestone cores after injection of both waste oil and diesel emulsified acids were performed and analyzed through a high resolution imaging and visualization software. From the laboratory results, the novel waste oil emulsified acid system showed a good potential as a stimulation fluid. For instance, it achieved lower pore volume of acid to break through (PVBT) compared to both conventional diesel emulsified acid and plain HCl. Moreover, diesel emulsion presented a better performance at lower injection rates whereas waste oil emulsion performed superiorly at higher rates. Thisindicates that, diesel emulsion is still better in terms of stimulation efficiency, however, waste oil emulsified acid still could be recommended in acid stimulation since it has low cost and acceptable performance. Furthermore, CT scan analysis shows that waste oil emulsified acid was capable of achieving narrow, branch-free, and deep wormhole which are the desired characteristic for any potential stimulation fluid. The novelty of this work comes from the fact that waste oil emulsified acid performance for carbonate acid stimulation has not been addressed before and hence this work to fill in the gap.