Themed collection Analytical Methods HOT Articles 2021

In this minireview, we have comprehensively discussed recent advances in the design principles and sensing mechanisms of developed probes and their biological/environmental applications in selective formaldehyde detection.

3D-printing enables the rapid prototyping of ion mobility (IMS) and mass spectrometry (MS) gadgets. The RepRap components are suitable for building cost-efficient robots and MS imaging systems. In this review, we present current trends.

Principal components analysis (PCA) is widely used in analytical chemistry, but is only one type of broader range of factor analysis tools that are described in this article.

Observations of band broadening under well-controlled laminar flow enable absolute, calibration-free determinations of diffusion coefficient.

This review highlights recent examples of point-of-care (POC) diagnostics for detecting nucleic acids, proteins, bacteria, and other biomarkers, all focused on highlighting the positive impact of POC on society and human health.

As the COVID-19 pandemic continues to escalate globally and acquires new mutations, accurate diagnostic technologies continue to play a vital role in controlling and understanding the epidemiology of this disease.

Real-world applications of single-particle ICP-MS are comprehensively and critically reviewed.

Metal–organic frameworks (MOFs) are highly ordered framework systems composed of metal centers and organic linkers formed through coordination bonds.

We report here the preparation of an activation-free Ni electrode through enrichment of hydroxyl functional groups via a base-catalyzed hydrolysis reaction on a “preanodized” screen printed carbon electrode.

The solid–liquid extraction capabilities of open port sampling interface mass spectrometry enabled rapid and sensitive detection of military-grade explosives, homemade explosive oxidizers, and narcotics, critical to screening applications.

A Hill-type FRET-based ratiometric pH probe (PHHF) was designed and synthesized for sensitively detecting minor pH variations of lysosomes.

Analysis of antioxidants in Chrysanthemum indici flos by online gradient extraction and HPLC-FRAP.

A simple method for determining total inorganic mercury (Hg) in solution using an enclosed quartz cell applying cold vapour-atomic absorption spectrometry (CV-AAS) can reduce sample volume, reductant, and cost compared with those of official methods.

A dual-wavelength excitation ratiometric fluorescent probe, HABA, was prepared to detect H₂S. HABA had excellent localization abilities toward mitochondria and lysosomes. HABA can not only detect exogenous H₂S, but it can also detect endogenous H₂S.

The assay based on Au NPs-Cu NCs showed selective response toward kanamycin within 2 minutes with a low LOD of 1.9/1.2 nM. The sensor possesses good reliability and accuracy, and can be applied for kanamycin detection in environmental water samples.

A dual signal amplification method has been developed for direct miRNA detection by combining the duplex-specific nuclease (DSN)-assisted recycling amplification and the nicking enzyme (NEase)-powered three dimensional (3D) DNA walker.

A novel Zn-LMOF was synthesized and exfoliated into ultrathin nanosheets to construct a stable sol–gel sensing system. It can sensitively sense pesticides such as imidacloprid, nitenpyram and dinotefuran via fluorescence quenching effect with very low detection limit (LOD).

A rapid and reliable UHPLC-Q-TOF-MS/MS method was successfully established to analyze the complex compounds in Yaobitong capsule and analyze their absorption states in biological samples, including urine, feces, and bile, after the oral administration of Yaobitong capsule.

Extraction based fluorometric method for high sensitive faecal pigment detection.

Level 3 details play essential roles in practical latent fingerprint (LFP) identification.

Here, simultaneous extraction and SERS detection of nicotine for rapid and reliable identification of nicotine release of snus products were performed based on nano-Au assembly hierarchy structure in the capillary.

A direct competitive nanozyme-linked immunosorbent assay (dcNLISA) based on MnO₂ nanosheets (MnO₂ NSs) as a nanozyme label was developed for the highly sensitive determination of fumonisin B₁ (FB₁).

A single reaction chamber microwave-assisted wet digestion system using O₂ as an auxiliary reagent and diluted HNO₃ for multisample digestion and metal determination.

A KPLS method combined with LIBS data reflects the non-linear relationships between LIBS spectra and the fuel property index being predicted.

The quality evaluation of hawthorn leaves in different geographical regions derived from the dried leaves of Crataegus pinnatifida Bge.

An NH₂-surface-coated wooden-tip electrospray ionization mass spectrometry method was developed for naphthenic acid analysis in water samples.

The metabolic change of patients (Crohn's disease (CD)/active CD (aCD)/inactive CD (iCD)) and healthy controls (HC) could be identified by measuring urine with surface-enhanced Raman spectroscopy (SERS).

FA-Poly-dA-ssDNA was attached to the 673 nm-dominated ECL nanomaterial GO/PTCDA-An to fabricate nuclease-free ultrasensitive FR sensors.

A highly emissive Zn(II)-pyridyl-benzimidazolyl-phenolato-based chemosensor is used in the solution-state and cost-effective ‘on-site’ solid-state contact mode detection of H₂PO₄⁻.

A novel photoelectrochemical biosensor based on SnO₂ nanoparticles was developed for detection of phosphatidylcholine in soybean oil.

New HPLC method to quantify levothyroxine in plasma samples was developed as per ICH and FDA, and was successfully applied in the determination of pharmacokinetic profiles after the administration of long-acting delivery systems in rats.

Protox inhibiting herbicides such as nitrofen have detrimental effects on the environment and human health.

An algebraic weighted library least squares method for gamma spectrum analysis is proven to make the analytical results more stable.

A new amorphous carbon-based dispersive micro solid-phase extraction method was developed for the extraction and preconcentration of several mycotoxins from soymilk samples.

The use of colorimetric sensors is encouraged by their simple operation, but limited by the lack of standardization. This article reports on a smartphone application to precisely readout urine strips via color mapping and RGB-to-HSV transposition.

This paper describes the development of a test kit for the naked-eye detection of glyphosate (GlyP) using a copper(II)-pyrocatechol violet complex immobilized on a C18 solid support.

Thiourea as a sulfur-containing compound accelerates the etching rate of gold nanorods (AuNRs) leading to a wide color change from brown to light brown, green, blue, purple, pink, and colorless.

The aim of the study is to develop a handheld device based on the colorimetric detection of Ba²⁺ metal in gunshot residue using gold nanoparticles capped with sodium malonate with great sensitivity and selectivity.

The mechanism for detecting H₂O₂ and glucose in the system of the NH₂-MIL-53(Al)-HRP enzymatic reaction.

CRISPR-Cas12a assisted rolling circle amplification for sensitive osteosarcoma diagnosis.

A report on a palm-sized dot blot-based device that allows simultaneous semi-quantitative comparison of up to five antibodies from different suppliers regarding their affinity/avidity, cross-reactivity, and batch-to-batch reliability.

The probe has excellent sensitivity, fast response and low limit of detection to HSO₃⁻. The mechanism was verified by density functional theory (DFT) and time-dependent DFT. The sensor has been successfully imaged in RAW264.7 cells.

For the first time, a InAlGaN based HEMT has been used for biosensing applications. Also, machine learning techniques are introduced in the modelling of the physics of a semiconductor device.

Improved propidium monoazide (PMAxx) and loop-mediated isothermal amplification (LAMP) were used to distinguish between viable and dead C. albicans. A portable microfluidic chip system was developed to detect multiple viable pathogens in parallel.

N-doped blue-fluorescence carbon dots (N-CDs) were fabricated via a one-pot hydrothermal method using folic acid and p-phenylenediamine.

Integrating capillary electrophoresis fingerprints and UV overall components dissolution consistency to give the overall quality control of Flos Chrysanthemi Indici preparation.

We present the first reported quantification of trace elements in plutonium via a portable laser-induced breakdown spectroscopy (LIBS) device and demonstrate the use of chemometric analysis to enhance the handheld device's sensitivity and precision.

A simple and immobilization-free homogeneous electrochemical biosensor for the detection of human papillomavirus (HPV-16) has been fabricated by combining with methylene blue (MB)-labeled probes toward the negatively-charged indium tin oxide (ITO) electrode.

Thermo-responsive nanogels, poly(NIPAM–AAM) were prepared by a facile method of free radical one-pot precipitation based on monomeric N-isopropylacrylamide (NIPAM).

Obesity is a key component of metabolic syndrome and is precipitated by complex interactions between multiple environmental and genetic factors.

LC-MS/MS and guest-host chemistry is a viable approach for the dual detection of organic and inorganic gunshot residue.

A quantitative immunochromatographic strip assay has been developed for rapid screening of lambda-cyhalothrin in foods.

Three new asymmetric BODIPY-based fluorescent probes were designed and synthesized for highly selective and sensitive detection of cysteine. These probes were able to image exogenous and endogenous Cys through green or red channels in living cells.

Bacitracin was immobilized on the surface of Fe₃O₄@PDA magnetic nanoparticles for the rapid enrichment and sensitive detection of Staphylococcus aureus (G⁺) and Klebsiella pneumoniae (G⁻) in biological samples combined with MALDI-TOF MS.

A schematic diagram of sensing cartap using the IFE between GSH-Cu NCs and Au NPs.

A new analytical method for combined separation of chiral and chiral antifungal agents in the environment has been developed.

Magnetic LF assay for rapid quantification of HBsAg in serum.

A sensitive fluorescent chiral sensor is developed based on the inner filter effect of chiral Au nanoparticles on MoS₂ quantum dots, which can be used for the discrimination of tyrosine isomers.

An effective turn-on ER-targeting fluorescent probe ER-DTT was designed to image DTT of endoplasmic reticulum for the first time.

Highly selective and rapid detection of silver ions by using a “turn on” non-fluorescent gold nanocluster probe.

We proposed an idea of separation-interrupted sequential injections (Sisi) to substantially increase the throughput of CE together with theory and experimental demonstration. The separation time of Sisi-CE-C⁴D/C⁴D is only 21% of that of normal CE.

In this paper, a ratiometric fluorescent probe for NAD(P)H derived from coumarin and hemicyanine was synthesized. The ratiometric fluorescent probe provided an important theoretical basis for sensing NAD(P)H.

Immunoassay of ionophore antibiotics, salinomycin and narasin, was first developed for milk analysis. Good recovery was promoted by the absence of Na⁺–K⁺ ions in tested samples.

Environmental water quality monitoring plays an important role in human health risk assessments for pharmaceuticals in water and pollutant source control.

In vitro fish gill model to study the branchial efflux of emerging contaminants at ever lower concentrations in freshwater.

A homo-FRET enhanced ratiometric fluorescence method has been developed successfully for the detection of Exo III activity.

A fully 3D-printed microfluidic thread-based device containing an embedded electrochemical detector is first reported. A green method based on microflow injection analysis for sensing of nitrite ions in environmental samples is also first presented.

The mathematical expression for the real-time current of the SECM tip and the imaging resolution has been derived, which revealed the effects of tip electrode size and tip–substrate distance on imaging resolution.

This study provided a new application of deep eutectic solvents (DESs) in the simultaneous extraction of phenolic acids and polysaccharides from the bulbs of Lilium lancifolium Thunb.

A separation method using pH-ZRCCC combined with HSCCC was proposed to separate the crude sample of Perillae Folium with different constituents and polarity, and three phenolic acids and four flavonoid glycosides were isolated successfully.