Lead halide perovskite nanocrystals (NCs) are promising optical materials in many fields. However, their poor moisture stability, significant toxicity, and difficulty to be further functionalized greatly hinder their applications in bioimaging. Here, a universal strategy is demonstrated by simply encapsulating CsPbX3 (X = Cl, Br, I) NCs into phospholipids to achieve CsPbX3–phospholipid micelles (CsPbX3@phospholipid) as probes for multiplex encoding cellular imaging or tumor-targeted imaging. The layer of phospholipids endows CsPbX3 NCs with superior water-resistant characteristics, the ability to be further biofunctionalized, and greatly improved biocompatibility. The CsPbX3@phospholipid micelles exhibited strong luminescence with narrow fwhm in water for more than four months. Specifically, even after being modified with folic acid, the bright fluorescence of the micelles was well retained, which were employed for the targeting of Hela cells. Finally, the greatly reduced toxicity of the CsPbX3@phospholipid micelles was verified using HeLa cells and zebrafish as in vitro and in vivo models, respectively.
As one of the novel two-dimensional nanomaterials, black phosphorus nanosheets (BP NS) have been proven to be excellent carrier materials for drugs, owing to their fine optical properties and biocompatibility. In this work, a composite drug nanocarrier based on BP NS is proposed, which can perform a synergetic and targeted chemophotothermal therapy of acute lymphoblastic leukemia (ALL). First, BP NS were prepared by an improved liquid exfoliation technique. Then, polyethylene glycol (PEG) was modified on the surfaces of BP NS through electrostatic adsorption. Drug molecules can also be loaded onto the BP NS via electrostatic adsorption. The PEG layer can effectively protect the interior BP NS from water and air to enhance their physiological stability. The obtained PEGylated BP NS (BP NS@PEG) not only demonstrated an excellent photothermal conversion efficiency and photothermal stability but also exhibited a good pH and photothermal dual-responsive drug release behavior. In addition, the BP NS@PEG were further modified with Sgc8 aptamers through covalent bonding. The aptamers provided an efficient specificity toward ALL cells (CCRF-CEM) and greatly increased the endocytosis of the nanocarriers through a receptor-mediated manner, which can further improve the therapeutic effect. Hence, the presented BP NS-based multifunctional nanocarrier can achieve a targeted and synergetic chemophotothermal therapy of ALL, which shows a promising potential in improving the curative efficiency.
Gas sensors lie at the heart of various fields ranging from medical to environmental sciences, and the demand of gas sensors is instantly expanding. However, in the face of complex gas samples, how to maintain high sensitivity while performing multiplex detection still puzzles the researchers. Here, by introducing Ti 3 C 2 T x MXene into a microfluidic gas sensor with a three-dimensional (3D) transferable SERS substrate, a powerful gas sensor having both multiplex detecting ability and high sensitivity is demonstrated. The employ of MXene endows the sensor with a universal high adsorption efficiency for various gases while the generation of in situ gas vortices in the sophisticated nanomicro structure extends the molecule residence time in SERS-active area, both leading to the increased sensitivity. In the proof-of-concept experiment, a limit of detection (LOD) of 10−50 ppb was achieved for three typical volatile organic compounds (VOCs) according to the intrinsic SERS signals of gas molecules. Besides, the welldesigned periodic 3D structure solves the general repeatability problem of SERS substrates. In addition, the detailed composition of gas mixture was revealed using classic least-square analysis (CLS) with an average accuracy of 90.6%. Further, a chromatic barcode was developed based on the results of CLS to read out the complex composition of samples visually. KEYWORDS: surface-enhanced Raman spectroscopy (SERS), volatile organic compounds (VOCs), self-assembly, MXene, Ti 3 C 2 T x , classic least-square analysis (CLS)
lightweight, portable, foldable, stretchable, and biocompatible are triggering the intense interests of researchers from multidisciplinary fields like biology, material science, and chemistry. [9][10][11] Nowadays, great attempts have been devoted to developing advanced flexible electronics by integrating various inorganic or organic traditional conductive functional materials with flexible electrochemically non-active elastic substrates. [12][13][14][15][16][17] Generally, traditional conductive functional materials encounter the shortcomings such as high price, inherent rigidity, weak biocompatibility, poor mechanical, and inferior interface bonding properties, which are employed to evaluate the performance of the flexible electronics materials. Therefore, pursuing these materials with practical applications is an emergent issue in the research field.Nevertheless, in numerous conductive functional materials, hydrogels with 3D network structures have been largely selected as the excellent candidates due to their high water content, excellent biocompatibility and biodegradability properties, high elasticity, and outstanding stimulus responsiveness. [18][19][20][21][22][23] Conductive hydrogels are generally constructed via integrating various conductive substances into the hydrogel matrix, which are comprised of carbon materials (carbon nanotubes (CNTs), graphite), metal oxides, metal sulfides, metal nanoparticles and conductive polymers (polyaniline (PANI), polypyrrole (PPy), poly (3,4-ethylenedioxythiophene) (PEDOT:PSS)). [24][25][26][27][28][29][30] For example, Han et al. fabricated a CNTs-based conductive hydrogel for strain sensors by in situ polymerization of acrylic acid and acrylamide in water/glycerol solutions in the presence of polydopamine-decorated CNTs. [28] Devaki et al. reported a 3D Ag nanoparticles-polyacrylic acid conductive hydrogel via combining in situ polymerization of acrylic acid and reduction of Ag + . [29] Duan et al. constructed a robust and force-sensitive conductive hydrogel employing synthesizing polyacrylamide and PANI in closely packed swollen chitosan microspheres. [30] According to the different configurations of hydrogels, conductive hydrogels are allowed to be processed into 3D bulk gels, 2D gel films, 1D gel fibers, and 0D microgels. [31][32][33][34][35][36] The mechanical flexibility of 1D fibrous configuration is superior to that of 3D bulk or 2D film configuration due to its well-oriented polymer chains, light weight, and low dimensions for flexible electronics. Moreover, ultra-flexible fibrous materials can be easily woven into diverse soft and breathable fabrics, which
detection of multiple biomarkers through rich spectral information. [8][9][10][11] However, most of these sensors use colorimetric signals, suffering from low sensitivity and photobleaching.Previous research results have demon strated that surfaceenhanced Raman scattering (SERS) spectroscopy is a powerful tool for the identification of trace analysts through their vibrational fingerprints, exhibiting high sensitivity, excellent multiplex detection ability, and photostability. [8,12,13] Especially, single mol ecule detection can be achieved when the biochemical molecules are confined at SERS "hotspots". [14][15][16] Although many plasmonic metamaterials generating fine "hotspots" have been designed, the appli cation of plasmonic sensors in wearable and inthefield SERS analysis is currently rare. Unlike the rigid sensors, a wearable one is usually a soft laminate to match the biointerfaces of arbitrary shapes (such as nose, epidermis, eye, and oral). Since SERS enhancement is sensitive to the excitation angles and the nanometerscale distributed "hotspots", the intensity of SERS signal is unstable during the bonding or stretching of the flexible sensors. [6,19] For instance, the SERS intensity of a monolayer of metal nano particles assembled on a flexible film decreased rapidly even when the film was slightly bent or stretched. [4,17,18] This problem also exists in most plasmonic sensors prepared by micro/nano fabrication technology. [17] Thus, for an accurate assessment of biomarkers, how to maintain the stability of SERS signal of a wearable sensor under a wide range of excitation angles, external mechanical wears, strains, or distortions during body movements is a great challenge.Here, inspired by the structure of a compound eye of Xenos Peckii that exhibits a wideangle detection ability (Figure 1a), [18,19] we proposed a wearable SERS sensor using omnidirectional plasmonic nanovoids array (OPNA) by a novel binary colloidal crystal (BCC) hotembossing method. Such an OPNA contains two parts in structure: 1) an artificial plasmonic compoundeye (APC) containing a microscale semisphere retina decorated with a "pockets" array in a honeycomb pattern; 2) a monolayer of metal nanoparticles assembled inside the "pockets" of APC, which can generate a plenty of SERSactive "hotspots". APC acts as an "armour" to protect the brittle nanoparticles array from mechanical strains or distortions, and endows OPNA with Surface-enhanced Raman spectroscopy (SERS) is a promising technology for wearable sensors due to its fingerprint spectrum and high detection sensitivity. However, since SERS-activity is sensitive to both the distribution of "hotspots" and excitation angle, it is profoundly challenging to develop a wearable SERS sensor with high stability under various deformations during movements. Herein, inspired by omnidirectional light-harvesting of the compound eye of Xenos Peckii, a wearable SERS sensor is developed using omnidirectional plasmonic nanovoids array (OPNA), which is prepared by assembling a monolayer of metal nanopa...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.