A fluorometric and colorimetric approach for the rapid detection of berberine hydrochloride based on an anionic polythiophene derivative

Plasmon-enhanced fluorescence combined with aptamer sensor based on Ag nanocubes for signal-amplified detection of berberine hydrochloride

Plasmon enhanced fluorescent (PEF) with more "hot spots" play a critical role in signal amplified technology to avoid the intrinsic limitation of fluorophore which ascribed to a strong electromagnetic field at the tip structure. However, application of PEF technique to obtain a highly sensitive analysis of medicine was still at a very early stage. Herein, a simple but versatile Ag nanocubes (Agcubes)-based PEF sensor combined with aptamer (Agcubes@SiO2-QDs-Apt) was proposed for highly sensitive detection of berberine hydrochloride (BH). The distance between the plasma Agcubes and the red-emitted CdTe quantum dots (QDs) were regulated by the thickness of silica spacer. The three-dimensional finite-difference time-domain (3D-FDTD) simulation further revealed that Agcubes have a higher electromagnetic field than Ag nanospheres. Compared with PEF sensor, signal QDs-modified aptamer without Agcubes (QDs-Apt) showed a 10-fold higher detection limit. The linear range and detection limit of the Agcubes@SiO2-QDs-Apt were 0.1-100 μM, 87.3 nM, respectively. Furthermore, the PEF sensor was applied to analysis BH in the berberine hydrochloride tablets, compound berberine tablet and urine with good recoveries of 98.25-102.05%. These results demonstrated that the prepared PEF sensor has great potential for drug quality control and clinical analysis.

Preparation of chitosan/SiO2 coated silver nanoclusters and its application in enhanced fluorescence detection of berberine hydrochloride

Although the synthesis and applications of the metal nanoclusters and silica coated metal noclusters were widely explored, however, the fluorescence sensing application of silica coated metal nanoclusters are still challenges. In this work, the composite nanoparticles (PEI-Ag NCs/CSNPs) were synthesized by coating polyethyleneimine capped silver nanoclusters (PEI-Ag NCs) with chitosan/silica through a reverse microemulsion method, and then used for fluorescence enhancement detection of berberine hydrochloride (BRH). UV-vis absorption spectra, fluorescence spectra, IR spectra, transmission electron microscope (TEM) and X-ray Photoelectron Spectroscopy (XPS) technique were used to reveal the possible binding relationship between PEI-AgNCs and chitosan/silica and fluorescence sensing mechanism of PEI-Ag NCs/CSNPs to BRH. The results showed that PEI-Ag NCs/CSNPs possess better sensing ability as compared to the free PEI- Ag NCs and can be successfully applied to evaluate the BRH content in actual medicine.

One-pot hydrothermal synthesis of Si-doped carbon quantum dots with up-conversion fluorescence as fluorescent probes for dual-readout detection of berberine hydrochloride

Here, the high fluorescent silicon-doped carbon quantum dots (Si-CQDs) were prepared by a facile and one-pot hydrothermal assay using 3-aminopropyltrimethoxysilane as the carbon and silicon source. The prepared Si-CQDs exhibit favorable water-soluble, high-temperature resistance, acid resistance, alkali resistance, high ionic strength resistance, high photostability, film-forming ability and solid-state fluorescence. Compared to other Si-CQDs that have been reported, the prepared Si-CQDs show unique up-conversion fluorescence. Furthermore, it is found that berberine hydrochloride (BH) can effectively quench the down- and up-conversion fluorescence of the Si-CQDs, making it can be used as a highly sensitive and specific probe for BH dual-mode sensing. Meanwhile, the linear range of down-conversion fluorescence detection for BH is 0.5-30.0 µmol/L with a limit of detection (LOD) of 50 nmol/L, and the linear range of up-conversion fluorescence assay for BH is 0-25.0 µmol/L. The mechanism of down-conversion fluorescence quenching by BH was investigated through a series of studies. The results show the quenching mechanism is the inner filter effect (IFE). Moreover, this proposed strategy has been well used to analyze BH in urine samples with satisfactory results.

A dual-mode optical assay for iron (II) and gallic acid based on Fenton reaction

The hydroxyl radicals (·OH) produced by the Fenton reaction of iron (II) and hydrogen peroxide (H₂ O₂ ) can oxidize the colorless 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized TMB (Ox-TMB), resulting in a decrease in the fluorescence intensity of the reaction system and an increase in ultraviolet absorption. Ox-TMB had a visible absorption peak at 625 nm and a fluorescence peak around 420 nm. When gallic acid (GA) was added to the system, Ox-TMB was reduced to TMB, which made the color of the system disappear and the fluorescence recover. The linear ranges for determination of iron (II) were 0.5-10 μM (fluorometric) and 0.5-20 μM (colorimetric), and the detection limits were 0.25 μM (fluorometric) and 0.28 μM (colorimetric). The linear ranges for determination of GA were 0-80 μM (fluorometric) and 0-60 μM (colorimetric), and the detection limits were 0.31 μM (fluorometric) and 0.8 μM (colorimetric). The results of anti-interference experiments shew that this dual-mode assay had very good selectivity for the determination of iron (II) and GA.

Smart Materials Enabled with Artificial Intelligence for Healthcare Wearables

Contemporary medicine suffers from many shortcomings in terms of successful disease diagnosis and treatment, both of which rely on detection capacity and timing. The lack of effective, reliable, and affordable detection and real‐time monitoring limits the affordability of timely diagnosis and treatment. A new frontier that overcomes these challenges relies on smart health monitoring systems that combine wearable sensors and an analytical modulus. This review presents the latest advances in smart materials for the development of multifunctional wearable sensors while providing a bird's eye‐view of their characteristics, functions, and applications. The review also presents the state‐of‐the‐art on wearables fitted with artificial intelligence (AI) and support systems for clinical decision in early detection and accurate diagnosis of disorders. The ongoing challenges and future prospects for providing personal healthcare with AI‐assisted support systems relating to clinical decisions are presented and discussed.

A cationic quantum dot-based ratiometric fluorescent probe to visually detect berberine hydrochloride in human blood serums

Berberine hydrochloride (BH) is an isoquinoline alkaloid normally used as drug to treat diseases. Compared with the traditional detection methods, the carbon quantum dots (CQDs) have better selectivity, high sensitivity, easy operation, and is inexpensive which could be widely utilized as fluorescent nanoprobes to detect various compounds quantificationally. And ratiometric fluorescent sensors conspicuously increase sensitivity and precision detection and improve quantification. In this work, we use water-soluble and fluorescent cationic carbon dots cetylpyridinium chloride monohydrate (CPC)-CQDs to connect with pinacyanol chloride (PC) and sodium tetraphenylborate (ST) as the ratiometric fluorescent probe to detect BH. The ratiometric fluorescent probe has high sensitivity towards alkaloids and metal ions, photochemical stability (60 min), and pH stability (from 6.0 to 8.0), with the detection range from 0 to 200 μM, and limit was as low as 57.35 nM. The accuracy of the method was verified by spiked recovery experiment in different human blood serums which were drawn from healthy adult volunteers to explore the practicability. The recoveries were in the range 94.34 to 105.48% with relative standard deviations (RSD) of 0.80 to 2.92%. In addition, we could observe that the fluorescence was gradually darkened, and the color turned yellow to realize the visual detection. It is expected that this work would open up a new strategy for detecting BH in the environment and human blood serums.