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Rotating cylindrical stamp-based nanoimprint technique has many advantages, including the continuous fabrication of intriguing micro/nanostructures and rapid pattern transfer on a large scale. Despite these advantages, the previous nanoimprint lithography has rarely been used for producing sophisticated nanoscale patterns on a non-planar substrate that has many extended applications. Here, the simple integration of nanoimprinting process with a help of a transparent stamp wrapped on the cylindrical roll and UV optical source in the core to enable high-throughput pattern transfer, particularly on a fabric substrate is demonstrated. Moreover, as a functional resin material, this innovative strategy involves a synergistic approach on the synthesis of molecularly imprinted polymer, which are spatially organized free-standing perforated nanostructures such as nano/microscale lines, posts, and holes patterns on various woven or nonwoven blank substrates. The proposed materials can serve as a self-encoded filtration medium for selective separation of formaldehyde molecules. It is envisioned that the combinatorial fabrication process and attractive material paves the way for designing next-generation separation systems in use to capture industrial or household toxic substances.

Vaccines are commonly administered by injection using needles. Although transdermal microneedles are less-invasive promising alternatives, needle-free topical vaccination without involving physical damage to the natural skin barrier is still sought after as it can further reduce needle-induced anxiety and simply administration. However, this long-standing goal has been elusive since the intact skin is impermeable to most macromolecules. Here, we show an efficient, non-invasive transdermal vaccination in mice by employing two key innovations: first, the use of hyaluronan (HA) as vaccine carriers and, second, non-ablative laser adjuvants. Conjugates of a model vaccine ovalbumin (OVA) and HA—HA-OVA conjugates—induced more effective maturation of dendritic cells in vitro, compared to OVA or HA alone, through synergistic HA receptor-mediated effects. Following topical administration in the back skin, HA-OVA conjugates penetrated into the epidermis and dermis in murine and porcine skins up to 30% of the total applied quantity, as revealed by intravital microscopy and quantitative fluorescence assay. Topical administration of HA-OVA conjugates significantly elevated both anti-OVA IgG antibody levels in serum and IgA antibody levels in bronchioalveolar lavage, with peak levels at 4 weeks, while OVA alone had a negligible effect. An OVA challenge at week 8 elicited strong immune-recall humoral responses. With pre-treatment of the skin using non-ablative fractional laser beams (1410 nm wavelength, 10 ms pulse duration, 0.2 mJ/pulse) as laser adjuvant, strong immunization was achieved with much reduced doses of HA-OVA (1 mg/kg OVA). Our results demonstrate the potential of the non-invasive patch-type transdermal vaccination platform.

probes are detected via their fl uorescence, i.e., spontaneous emission. [ 9 ] However, here, we show that integrating these probes into an optical resonator turns them into an optical gain medium supporting effi cient stimulated emission with distinct spectral characteristics. Advantageously, this approach provides a fast and simple method to obtain lasing from normal cells within less than 1 h by using a biocompatible cell-tracker dye that becomes highly fl uorescent upon entering the cytoplasm, thus forming a localized gain volume. We demonstrate lasing with this approach from both spherical cells in suspension and from elongated, adherent cells grown and stained directly on one of the refl ectors forming the cavity. Fluorescent dyes offer a convenient method for transforming normal cells into biolasers for a variety of applications in cell-culture and lab-on-a-chip settings. In the present study, we have exploited 5-chloromethylfl uorescein diacetate (CMFDA, CellTracker Green CMFDA, Invitrogen) to investigate the feasibility of using fl uorescent probes for intracellular gain as a convenient alternative to fl uorescent proteins. The cell tracker dye CMFDA is widely used to stain cells for tracking and monitoring. [ 10 ] Besides bright fl uorescence and good photostability, it offers two further advantageous features in the context of providing optical gain in cells. First, CMFDA molecules are originally nonabsorbing and nonfl uorescent, but transform into a highly fl uorescent form once they enter the cytosol of a cell. This property is due to cleavage of the acetate groups from the molecular core by intracellular esterases, which produces a highly bright, fl uorescein derivative, 5-chloromethylfl uorescein (CMF) ( Figure 1 a). Second, a subsequent reaction of the chloromethyl group of CMF with the thiol groups of intracellular proteins yields a form that can no longer penetrate the cell membrane, thus confi ning the fl uorescent form of the dye to the inside of the cell. We confi rmed that CMF is well retained within the cytosol for over 72 h. By contrast, conventional dyes, such as fl uorescein, leak out of cells within 1 h (Figure 1 b). In terms of its spectral properties, the intracellular form of the dye is similar to the green fl uorescent protein that was previously used for cell lasers, its excitation and emission spectra peak at 493 and 522 nm, respectively (Figure 1 c). The dramatic shift in cell membrane permeability of CMDFA helps achieve high intracellular concentration (Figure S1, Supporting Information), which can provide high gain and, therefore, facilitate lasing. We incubated HeLa cells with 100 × 10 −6 M of CMFDA dye in serum-free medium containing 1% dimethyl sulfoxide (DMSO) for 30 min under standard culture conditions. This concentration is four times higher than the A Simple Approach to Biological Single-Cell Lasers Via Intracellular Dyes

The temperature-responsive poly(N-isopropylacrylamide) [PNIPAAm] has been exploited for various biomedical applications. In this work, poly(N-isopropylacrylamide-co-dopamine methacrylamide) [P(NIPAAm-co-DMAAm)] was synthesized for facile surface modification and application to cell sheets. 1H NMR, FT-IR, and GPC confirmed the successful synthesis of P(NIPAAm-co-DMAAm). The lower critical solution temperature was measured to be ca. 29.2 °C by UV–Vis spectroscopy. AFM imaging clearly visualized the transient phase transition of the temperature-responsive polymer bound on silicon substrate by coordination bond formation. Furthermore, the adhesive and temperature responsive P(NIPAAm-co-DMAAm) could be successfully applied to the facile preparation of NIH-3T3 fibroblast cell sheets.

Among various 2D nanomaterials, molybdenum disulfide (MoS2 ) exhibits unique visible photoluminescence with high absorption at the near-infrared (NIR) range. Despite these optical properties, the efforts to use MoS2 nanomaterials for optical imaging and photothermal therapy are hampered by their instability and low intracellular delivery efficiency. Multifunctional MoS2 conjugated with hyaluronate (HA) for cancer theranosis is reported herein. HA facilitates the delivery of MoS2 to tumor cells by the HA-receptor mediated endocytosis. In BALB/c nude mice inoculated with a colorectal cancer cell line of HCT116, HA-MoS2 conjugates appear to be accumulated in the primary tumor at a content more than that in the liver and kidney. The disulfide bonding between MoS2 and thiolated HA seems to degrade in the cytoplasm, releasing MoS2 sheets in stacks and enhancing luminescence efficiency. The HA-MoS2 conjugates are readily detected via photoacoustic imaging as well as upconversion and downconversion fluorescence imaging. With NIR light illumination, HA-MoS2 conjugates enable highly effective photothermal tumor ablation. All these results confirm the promising potential of HA-MoS2 conjugates for cancer theranosis.

The last decade has seen dramatic progress in the principle, design, and fabrication of photonic nanomaterials with various optical properties and functionalities. Light-emitting and light-responsive nanomaterials, such as semiconductor quantum dots, plasmonic metal nanoparticles, organic carbon, and polymeric nanomaterials, offer promising approaches to low-cost and effective diagnostic, therapeutic, and theranostic applications. Reasonable endeavors have begun to translate some of the promising photonic nanomaterials to the clinic. Here, current research on the state-of-the-art and emerging photonic nanomaterials for diverse biomedical applications is reviewed, and the remaining challenges and future perspectives are discussed.

The effect of chemical modification of hyaluronic acid (HA) on its distribution throughout the body was successfully visualized in nude mice through real-time bioimaging using quantum dots (QDots). Adipic acid dihydrazide modified HA (HA-ADH) was synthesized and conjugated with QDots having carboxyl terminal ligands activated with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysulfosuccinimide. The formation of HA-QDot conjugates could be confirmed by gel permeation chromatography, fluorometry, transmission electron microscopy, and ζ-size analysis. According to the real-time bioimaging of HA-QDot conjugates after subcutaneous injection to nude mice, the fluorescence of HA-QDot conjugates with a near infrared wavelength of 800 nm could be detected up to 2 months, whereas that with an emission wavelength of 655 nm disappeared almost completely within 5 days. The results can be ascribed to the fact that near-infrared light has a high penetration depth of about 5–6 cm in the body compared to that of about 7–10 mm for visible light. Thereby, using QDots with a near-infrared emission wavelength of 800 nm, the distribution of HA-QDot conjugates throughout the body was bioimaged in real-time after their tail-vein injection into nude mice. HA-QDot conjugates with 35 mol% ADH content maintaining enough binding sites for HA receptors were mainly accumulated in the liver, while those with 68 mol% ADH content losing much of HA characteristics were evenly distributed to the tissues in the body. The results are well matched with the fact that HA receptors are abundantly present in the liver with a high specificity to HA molecules. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 1144–1153, 2008. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com

The reactivity of 3,5-1H-diamino-1,2,4-triazole (DAT) in condensation reactions with acetic anhydride, aromatic dianhydrides and diacyl chlorides was investigated. In comparison to ordinary aromatic diamines. the primary amino groups of DAT were found to have relatively low reactivities so that they are partially involved in the reactions. In contrast, the secondary amino group of DAT was determined to be so reactive that it is always involved completely in the reactions. The reactivities of the amino groups in DAT were found to decrease in the order =NH(1) » -NH 2 (3) » -NH 2 (5). The low reactivites of the primary amino groups in DAT might be attributed to the relatively high electronegativity of the heterocyclic five-membered nitrogens, the imino characteristics of the primary amino groups via tautomerization, and the amidization of the reactive secondary amino group and the resultant steric hinderance. Because of the limited reactivities, polymers with high molecular weight could not be synthesized from DAT with diacyl chlorides and dianhydrides.