Exosomes have recently come into focus as “natural nanoparticles” for use as drug delivery vehicles. Our objective was to assess the feasibility of an exosome-based drug delivery platform for a potent chemotherapeutic agent, paclitaxel (PTX), to treat MDR cancer. Herein, we developed and compared different methods of loading exosomes released by macrophages with PTX (exoPTX), and characterized their size, stability, drug release, and in vitro antitumor efficacy. Reformation of the exosomal membrane upon sonication resulted in high loading efficiency and sustained drug release. Importantly, incorporation of PTX into exosomes increased cytotoxicity more than 50 times in drug resistant MDCKMDR1 (Pgp+) cells. Next, our studies demonstrated a nearly complete co-localization of airway-delivered exosomes with cancer cells in a model of murine Lewis Lung Carcinoma pulmonary metastases, and a potent anticancer effect in this mouse model. We conclude that exoPTX holds significant potential for the delivery of various chemotherapeutics to treat drug resistant cancers.

Exosomes offer distinct advantages that uniquely position them as highly effective drug carriers. Comprised of cellular membranes with multiple adhesive proteins on their surface, exosomes are known to specialize in cell–cell communications and provide an exclusive approach for the delivery of various therapeutic agents to target cells. In addition, exosomes can be amended through their parental cells to express a targeting moiety on their surface, or supplemented with desired biological activity. Development and validation of exosome-based drug delivery systems are the focus of this review. Different techniques of exosome isolation, characterization, drug loading, and applications in experimental disease models and clinic are discussed. Exosome-based drug formulations may be applied to a wide variety of disorders such as cancer, various infectious, cardiovascular, and neuro-degenerative disorders. Overall, exosomes combine benefits of both synthetic nanocarriers and cell-mediated drug delivery systems while avoiding their limitations.

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The surface-enhanced Raman scattering of benzenethiol was investigated in a silver sol. It was found that benzenethiol was chemisorbed dissociatively on the silver surface by rupture of its S-H bond and the benzenethiolate formed on adsorption was bound to silver via its sulphur atom. Using the electromagnetic surface selection rule, the orientation of the benzene ring with respect to the surface plane could not be determined conclusively. However, it seemed likely that benzenethiol was adsorbed face-on to the silver surface.

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Surface-enhanced Raman scattering (SERS) of lY4-benzenedithiol (1 ,4-BDT) has been investigated in aqueous silver sol. The vibrational assignment of 1,4-BDT and its dianion species has been made by referring to that of 1,4-dichlorobenzene. From the SER spectrum, the 1,4-BDT molecule was found to chemisorb on the silver surface via Ag-S bonds after deprotonation, assuming a flat orientation with respect to the surface. The definitive orientation allowed us to test the validity of some SERS selection rules. Although the direct surface-benzene ring n interaction should result in a substantial increase of the bandwidths of ring modes, peak shifts alone seemed not to secure the presence of such an interaction. The tactics to classify the ring modes into the so-called in-plane and out-of-plane modes seemed also not pertinent in determining the orientation of benzene derivatives adsorbed on metal surfaces by virtue of SER spectra. A more unequivocal SERS selection is expected to be established in the near future since even the symmetry-based electromagnetic selection rule did not work in the present system.

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This paper presents the realization of a wearable thermoelectric generator (TEG) in fabric for use in clothing. A TEG was fabricated by dispenser printing of Bi 0.5 Sb 1.5 Te 3 and Bi 2 Se 0.3 Te 2.7 in a polymer-based fabric. The prototype consisted of 12 thermocouples connected by conductive thread over an area of 6 × 25 mm 2 . The device generated a power of 224 nW for a temperature difference of 15 K. When the TEG was used on the human body, the measured output power was 224 nW in an ambient temperature of 5 °C. The power of the TEG was affected by the movement of the wearer. A higher voltage was maintained while walking than in a stationary state. In addition, the device did not deform after it was bent and stretched several times. The prospect of using the TEG in clothing applications was confirmed under realistic conditions.