DNA hydrogels have received considerable attention in analytical science, however, some limitations still exist in the applications of intelligent hydrogels. In this paper, we describe a way to ...prepare gel film in a capillary tube based on the thermal reversible principle of DNA hydrogel and the principle of capillary action. Because of the slight change in the internal structure of gel, its permeability can be increased by the addition of some specific targets. The capillary behavior is thus changed due to the different permeability of the hydrogel film. The duration time of the target solution flowing through the capillary tube with a specified length is used to quantify this change. With this proposed method, ultra-trace DNA hydrogel (0.01 μL) is sufficient to realize the sensitive detection of cocaine without the aid of other instruments, which has a low detection limit (1.17 nM) and good selectivity.
Conductive patterns with line widths of 5–10 µm are successfully fabricated by utilizing the coffee‐ring effect in inkjet printing, resulting in transmittance values of up to 91.2% in the visible to ...near‐infrared region. This non‐lithographic approach broadens the range of fabrication procedures that can be used to create various nanoparticle‐based microstructures and electronic devices.
As a non-invasive visualization technique, photoluminescence imaging (PLI) has found its huge value in many biological applications associated with intracellular process monitoring and early and ...accurate diagnosis of diseases. PLI can also be combined with therapeutics to build imaging-guided theragnostic platforms for achieving early and precise treatment of diseases. Photodynamic therapy (PDT) as a quintessential phototheranostics technology has gained great benefits from the combination with PLI. Recently, aggregation-induced emission (AIE)-active materials have emerged as one of the most promising bioimaging and phototheranostic agents. Most of AIEgens, however, need to be chemically engineered to form versatile nanocomposites with improved their photophysical property, photochemical activity, biocompatibility, etc. In this review, we focus on three categories of AIE-active nanocomposites and highlight their application progresses in the intracellular biological process monitoring and PLI-guided PDT. We hope this review can guide further development of AIE-active nanocomposites and promote their practical applications for monitoring intracellular biological processes and imaging-guided PDT.
Thymol has been shown to be a safe and effective broad-spectrum antimicrobial agent that can be used as a food preservative. However, its volatile characteristics and strong odor limit its use in ...food products. The microencapsulation of this essential oil in biopolymers could overcome these disadvantages. In this work, thymol-loaded poly(lactide-co-glycolide) (PLGA) microparticles were successfully prepared and the optimal encapsulation efficiency was obtained at 20% (w/w) thymol. Microparticles containing thymol presented a spherical shape and smooth surface. Microencapsulation significantly improved the thermal and storage stability of thymol. In vitro release profiles demonstrated an initial fast release followed by a slow and sustained release. Thymol-loaded microparticles had strong antibacterial activity against
and
, and the effectiveness of their antibacterial properties was confirmed in a milk test. Therefore, the thymol-loaded microparticles show great potential for use as an antimicrobial and as preservation additives in food.
The study aimed to develop a nanofiber film for photocatalytic degradation of ethylene and slowing down the ripening of banana fruit. Nanofibers containing different amounts of TiO2 nanoparticles ...(1 wt%, 5 wt%, and 10 wt%) were prepared using electrospinning method. Nanofibers containing 5 wt% TiO2 exhibited a nano-scale structure, good nanoparticle uniformity, and an anatase phase as characterized by scanning electron microscopy, energy dispersive X-ray spectrometer, transmission electron microscopy, and X-ray diffraction. Nanofibers containing 5 wt% TiO2 were tested in a photocatalytic reactor and showed higher photocatalytic activity for the degradation of ethylene. The utility of the photocatalytic reaction was further confirmed via a banana fruit-ripening test. The TiO2 nanofiber successfully delayed the color change and softening of bananas during storage. The results suggest that the TiO2 nanofiber offers photocatalytic degradation of ethylene and could potentially be used as packaging material for delaying postharvest fruit ripening.
Baicalin is one of the most abundant flavonoids found in the dried roots of
Georgi (SBG) belonging to the genus
. While baicalin is demonstrated to have anti-inflammatory, antiviral, antitumor, ...antibacterial, anticonvulsant, antioxidant, hepatoprotective, and neuroprotective effects, its low hydrophilicity and lipophilicity limit the bioavailability and pharmacological functions. Therefore, an in-depth study of baicalin's bioavailability and pharmacokinetics contributes to laying the theoretical foundation for applied research in disease treatment. In this view, the physicochemical properties and anti-inflammatory activity of baicalin are summarized in terms of bioavailability, drug interaction, and inflammatory conditions.
This review (with 187 refs.) summarizes the progress that has been made in the design of lateral flow biosensors (LFBs) based on the use of micro- and nano-materials. Following a short introduction ...into the field, a first section covers features related to the design of LFBs, with subsections on strip-based, cotton thread-based and vertical flow- and syringe-based LFBs. The next chapter summarizes methods for sample pretreatment, from simple method to membrane-based methods, pretreatment by magnetic methods to device-integrated sample preparation. Advances in flow control are treated next, with subsections on cross-flow strategies, delayed and controlled release and various other strategies. Detection conditionst and mathematical modelling are briefly introduced in the following chapter. A further chapter covers methods for reliability improvement, for example by adding other validation lines or adopting different detection methods. Signal readouts are summarized next, with subsections on color-based, luminescent, smartphone-based and SERS-based methods. A concluding section summarizes the current status and addresses challenges in future perspectives.
Graphical abstract
Recent development and breakthrough points of lateral flow biosensors.
A sensitive nucleic acid detection platform based on superhydrophilic microwells spotted on a superhydrophobic substrate is fabricated. Due to the wettability differences, ultratrace DNA molecules ...are enriched and the fluorescent signals are amplified to allow more sensitive detection. The biosensing interface based on superwettable materials provides a simple and cost‐effective way for ultratrace DNA sensing.
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