Screening of Acrylamide of Par-Fried Frozen French Fries Using Portable FT-IR Spectroscopy

Current assays for acrylamide screening rely heavily on LC-MS/MS or GC-MS, techniques that are not suitable to support point of manufacturing verification because it can take several weeks to receive results from a laboratory. A portable sensor that can detect acrylamide levels in real-time would enable in-house testing to safeguard both the safety of the consumer and the economic security of the agricultural supplier. Our objective was to develop a rapid, accurate, and real-time screening technique to detect the acrylamide content in par-fried frozen French fries based on a portable infrared device. Par-fried French fries (n = 70) were manufactured at times ranging from 1 to 5.5 min at 180 °C to yield a wide range of acrylamide levels. Spectra of samples were collected using a portable FT-IR device operating from 4000 to 700 cm⁻¹. Acrylamide was extracted using QuEChERS and quantified using uHPLC-MS/MS. Predictive algorithms were generated using partial least squares regression (PLSR). Acrylamide levels in French fries ranged from 52.0 to 812.8 µg/kg. The best performance of the prediction algorithms required transformation of the acrylamide levels using a logarithm function with models giving a coefficient of correlation (Rcv) of 0.93 and RPD as 3.8, which means the mid-IR model can be used for process control applications. Our data corroborate the potential of portable infrared devices for acrylamide screening of high-risk foods.     

磷光软盐配合物及其光电应用研究

磷光软盐配合物是一种通过静电力和范德华力结合的带有相反电荷金属配合物的光电材料,它们的发射光谱通常由两个独立部分组成.与单组分磷光金属配合物相比,磷光软盐配合物含有更丰富的激发态,不同组分之间还存在能量传递过程.最近几年,磷光软盐配合物作为一类新兴的光电材料,在不同的光电领域表现出潜在的应用前景,并取得了一定的进展.本综述详细介绍了磷光软盐的合成与光物理性质,并对它们在有机发光二极管、生物成像、光动力治疗、电致发光变色等领域的应用进行了总结.     

Development of Ultrahigh Permeance Hollow Fiber Membranes via Simple Surface Coating for CO2/CH4 Separation

Most researchers focused on developing highly selective membranes for CO₂/CH₄ separation, but their developed membranes often suffered from low permeance. In this present work, we aimed to develop an ultrahigh permeance membrane using a simple coating technique to overcome the trade-off between membrane permeance and selectivity. A commercial silicone membrane with superior permeance but low CO₂/CH₄ selectivity (in the range of 2–3) was selected as the host for surface modification. Our results revealed that out of the three silane agents tested, only tetraethyl orthosilicate (TEOS) improved the control membrane’s permeance and selectivity. This can be due to its short structural chain and better compatibility with the silicone substrate. Further investigation revealed that higher CO₂ permeance and selectivity could be attained by coating the membrane with two layers of TEOS. The surface integrity of the TEOS-coated membrane was further improved when an additional polyether block amide (Pebax) layer was established atop the TEOS layer. This additional layer sealed the pin holes of the TEOS layer and enhanced the resultant membrane’s performance, achieving CO₂/CH₄ selectivity of ~19 at CO₂ permeance of ~2.3 × 10⁵ barrer. This performance placed our developed membrane to surpass the 2008 Robeson Upper Boundary.     

Induction of Apoptosis via Inactivating PI3K/AKT Pathway in Colorectal Cancer Cells Using Aged Chinese Hakka Stir-Fried Green Tea Extract

Food extract supplements, with high functional activity and low side effects, play a recognized role in the adjunctive therapy of human colorectal cancer. The present study reported a new functional beverage, which is a type of Chinese Hakka stir-fried green tea (HSGT) aged for several years. The extracts of the lyophilized powder of five HSGT samples with different aging periods were analyzed with high-performance liquid chromatography. The major components of the extract were found to include polyphenols, catechins, amino acids, catechins, gallic acid and caffeine. The tea extracts were also investigated for their therapeutic activity against human colorectal cancer cells, HT-29, an epithelial cell isolated from the primary tumor. The effect of different aging time of the tea on the anticancer potency was compared. Our results showed that, at the cellular level, all the extracts of the aged teas significantly inhibited the proliferation of HT-29 in a concentration-dependent manner. In particular, two samples prepared in 2015 (15Y, aged for 6 years) and 2019 (19Y, aged for 2 years) exhibited the highest inhibition rate for 48 h treatment (cell viability was 50% at 0.2 mg/mL). Further, all the aged tea extracts examined were able to enhance the apoptosis of HT-29 cells (apoptosis rate > 25%) and block the transition of G1/S phase (cell-cycle distribution (CSD) from <20% to >30%) population to G2/M phase (CSD from nearly 30% to nearly 10%) at 0.2 mg/mL for 24 h or 48 h. Western blotting results also showed that the tea extracts inhibited cyclin-dependent kinases 2/4 (CDK2, CDK4) and CylinB1 protein expression, as well as increased poly ADP-ribose polymerase (PRAP) expression and Bcl2-associated X (Bax)/B-cell lymphoma-2 (Bcl2) ratio. In addition, an upstream signal of one of the above proteins, phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signalling, was found to be involved in the regulation, as evidenced by the inhibition of phosphorylated PI3K and AKT by the extracts of the aged tea. Therefore, our study reveals that traditional Chinese aged tea (HSGT) may inhibit colon cancer cell proliferation, cell-cycle progression and promoted apoptosis of colon cancer cells by inactivating PI3K/AKT signalling.     

Qualitative and Quantitative Analysis of Ejiao-Related Animal Gelatins through Peptide Markers Using LC-QTOF-MS/MS and Scheduled Multiple Reaction Monitoring (MRM) by LC-QQQ-MS/MS

Donkey-hide gelatin, also called Ejiao (colla corii asini), is commonly used as a food health supplement and valuable Chinese medicine. Its growing popular demand and short supply make it a target for fraud, and many other animal gelatins can be found as adulterants. Authentication remains a quality concern. Peptide markers were developed by searching the protein database. However, donkeys and horses share the same database, and there is no specific marker for donkeys. Here, solutions are sought following a database-independent strategy. The peptide profiles of authentic samples of different animal gelatins were compared using LC-QTOF-MS/MS. Fourteen specific markers, including four donkey-specific, one horse-specific, three cattle-specific, and six pig-specific peptides, were successfully found. As these donkey-specific peptides are not included in the current proteomics database, their sequences were determined by de novo sequencing. A quantitative LC-QQQ multiple reaction monitoring (MRM) method was further developed to achieve highly sensitive and selective analysis. The specificity and applicability of these markers were confirmed by testing multiple authentic samples and 110 batches of commercial Ejiao products, 57 of which were found to be unqualified. These results suggest that these markers are specific and accurate for authentication purposes.     

Synthesis of Mixed Arylalkyl Tertiary Phosphines via the Grignard Approach

Trialkyl and triaryl phosphines are important classes of ligands in the field of catalysis and materials research. The wide usability of these low-valent phosphines has led to the design and development of new synthesis routes for a variety of phosphines. In the present work, we report the synthesis and characterization of some mixed arylalkyl tertiary phosphines via the Grignard approach. A new asymmetric phosphine is characterized extensively by multi-spectroscopic techniques. IR and UV–Vis spectra of some selected compounds are also compared and discussed. Density functional theory (DFT)-calculated results support the formation of the new compounds.     

Photochemical Degradation of the UV Filter Octyl Methoxy Cinnamate Probed via Laser-Interfaced Mass Spectrometry

Octyl methoxycinnamate (OMC) is a common UVA and UVB filter molecule that is widely used in commercial sunscreens. Here, we used gas-phase laser photodissociation spectroscopy to characterise the intrinsic photostability and photodegradation products of OMC by studying the system in its protonated form, i.e., [OMC·H]⁺. The major photofragments observed were m/z 179, 161, and 133, corresponding to fragmentation on either side of the ether oxygen of the ester group (m/z 179 and 161) or the C–C bond adjacent to the ester carbonyl group. Additional measurements were obtained using higher-energy collisional dissociation mass spectrometry (HCD-MS) to identify fragments that resulted from the breakdown of the vibrationally hot electronic ground state. We found that the m/z 179 and 161 ions were the main fragments produced by this route. Notably, the m/z 133 ion was not observed through HCD-MS, revealing that this product ion is only produced through a photochemical route. Our results demonstrate that UV photoexcitation of OMC is able to access a dissociative excited-state surface that uniquely leads to the rupture of the C–C bond adjacent to the key ester carbonyl group.     

An efficient and convenient transformation of α-haloketones to α-hydroxyketones using cesium formate

A new safe and convenient transformation has been developed. In the presence of cesium formate in dry MeOH solution, α-haloketones underwent direct conversion reaction to afford α-hydroxyketone in excellent yields. Furthermore, this methodology can be extended and applied in 2-chloro-N-(1,3-diphenyl-1H-pyrazol-5-yl)acetamide, 2-chloro-N-(2,6-dimethylphen-yl)acetamide, 1-(bromomethylsulfonyl)benzene, and N-(bromomethyl)phthalimide to give the corresponding products in moderate to excellent yields.     

Optimal conditions and sample storage for the determination of H2O2 in marine waters by the scopoletin-horseradish peroxidase fluorometric method

The conditions presently in use for the fluorometric determination of H₂O₂ in marine waters, by reacting H₂O₂ with scopoletin in the presence of horseradish peroxidase (HRP) and measuring the quenching of the fluorescence intensity of scopoletin, are not the optimal conditions. Under the optimized conditions of a pH of 8.5–9.5, an excitation wavelength of 390 nm and an emission wavelength of 460, the sensitivity of the method can be increased significantly, by up to more than a factor of 3 and the variations in the sensitivity from sample to sample can be significantly reduced. Furthermore, the samples need not be analyzed immediately after sample collection as presently prescribed. After scopoletin and HRP have been added to a sample immediately after sample collection, the sample may be stored at room temperature in the dark for up to four days before the quenched fluorescence intensity of scopoletin is read.