1.Key Issues and Research Ideas of Traditional Chinese Medicine Anti-aging Guided by Essence-Qi-spirit Theory of Qiluo Doctrine
Peipei JIN ; Liping CHANG ; Cong WEI ; Mengnan LI ; Hui QI ; Hongrong LI ; Yunlong HOU ; Zhenhua JIA
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(9):240-246
Aging has emerged as a cutting edge and hotspot in global life science field, with anti-aging and geriatric disease prevention and treatment becoming critical issues urgently demanding solutions in international medical communities. In the face of the challenge of accelerating global population aging, in-depth exploration of aging mechanisms and the development of effective intervention strategies hold significant scientific and clinical value. This study supported by the national key research and development program of China, employed the essence-Qi-spirit theory of Qiluo doctrine as its guiding framework, focusing on the key scientific issue of the core traditional Chinese pathogenesis of aging, namely "depletion of kidney essence, deficiency of primordial Qi, and impairment of body and spirit". The treatment principle of "tonifying the kidney to replenish essence, harmonizing Yin and Yang, warming and invigorating primordial Qi, and nourishing the body and spirit" was established. Centered on holistic aging, systemic aging, and aging-related diseases, the research integrated multidisciplinary research approaches to construct multi-modal aging models and a multi-dimensional evaluation system, and it utilized multi-omics technologies to deeply analyze aging mechanisms. By systematically reviewing historical kidney-tonifying and anti-aging formulas and combining big data with artificial intelligence technologies, an information database of anti-aging traditional Chinese medicine substance was developed to reveal the differences and synergistic effects of various treatment methods and formulas on anti-aging. Based on this treatment method, the research integrated two millennia of kidney-tonifying medicinal experience to develop the innovative anti-aging traditional Chinese medicine, namely Bazhi Bushen capsules. It was validated that this capsule can delay holistic and systemic aging through multiple targets and mechanisms, thereby elucidating the scientific connotation of the essence-Qi-spirit theory of Qiluo doctrine in guiding anti-aging research from multiple dimensions and providing robust support for leveraging the advantages of traditional Chinese medicine to occupy the commanding heights of international anti-aging research.
2.The Role and Molecular Mechanism of N⁶-methyladenosine Modification in Spermatogenesis
Shi-Qi MENG ; Wen-Ting LU ; Xu CHENG ; Fan YANG ; Chang-Min NIU ; Ying ZHEGN
Progress in Biochemistry and Biophysics 2026;53(5):1297-1312
Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N6-methyladenosine (m6A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m6A methyltransferases (“writers”) catalyze the addition of a methyl group to the N6 position of adenosine, m6A demethylases (“erasers”) remove the modification, and m6A-binding proteins (“readers”) recognize m6A-modified transcripts. Through the coordinated actions of these factors, m6A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m6A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m6A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m6A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m6A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m6A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m6A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m6A-related proteins can function through noncanonical mechanisms independent of m6A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m6A regulatory system. Dysregulation of m6A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m6A-dependent and -independent mechanisms, the spatiotemporal dynamics of m6A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m6A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.
3.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.
4.The Role and Molecular Mechanism of N⁶-methyladenosine Modification in Spermatogenesis
Shi-Qi MENG ; Wen-Ting LU ; Xu CHENG ; Fan YANG ; Chang-Min NIU ; Ying ZHEGN
Progress in Biochemistry and Biophysics 2026;53(5):1297-1312
Spermatogenesis is a highly ordered and spatiotemporally regulated developmental process in the male reproductive system, during which spermatogonial stem cells (SSCs), supported by the seminiferous tubule microenvironment, sequentially undergo mitosis, meiosis, and spermiogenesis to ultimately generate structurally intact spermatozoa. This complex process is accompanied by extensive transcriptional reprogramming, chromatin remodeling, and finely tuned post-transcriptional regulation. Precise control of RNA fate is therefore essential for maintaining the continuity and fidelity of spermatogenesis, and its disruption represents a major molecular basis of male infertility. N6-methyladenosine (m6A), the most abundant internal RNA modification in eukaryotes, has emerged as a critical regulator of post-transcriptional gene expression. m6A methyltransferases (“writers”) catalyze the addition of a methyl group to the N6 position of adenosine, m6A demethylases (“erasers”) remove the modification, and m6A-binding proteins (“readers”) recognize m6A-modified transcripts. Through the coordinated actions of these factors, m6A regulates transcript fate at multiple levels, including RNA splicing, nuclear export, stability, translation, and decay. Emerging evidence indicates that m6A-mediated regulation is essential across multiple stages of spermatogenesis, including SSC self-renewal and differentiation, meiotic progression, maintenance of chromosomal stability, and sperm morphogenesis. Beyond its intrinsic functions in germ cells, m6A also contributes to the regulation of the testicular microenvironment. In sertoli cells, m6A is involved in maintaining blood-testis barrier integrity, RNA processing, and paracrine signaling, thereby providing structural and metabolic support for germ cell development. In Leydig cells, m6A regulates steroidogenesis, particularly testosterone synthesis, and participates in cellular stress responses and metabolic homeostasis. Through these mechanisms, m6A indirectly influences spermatogenesis by modulating the functional state of testicular somatic cells, highlighting an integrated regulatory mode that combines cell-intrinsic and microenvironment-mediated effects. Notably, distinct classes of m6A regulators exhibit pronounced stage-specific functions and coordinated division of labor, collectively forming a multilayered and dynamic regulatory network. Writers often display dosage- and temporal window-dependent effects; erasers contribute to stage-specific demethylation and functional compensation; while readers function through a “switch-buffer” dual-layer architecture, and RNA-binding proteins (RBPs) participate in substrate selection and post-transcriptional regulation. Importantly, emerging evidence suggests that some m6A-related proteins can function through noncanonical mechanisms independent of m6A recognition, such as intrinsic RNA-binding activity, helicase function, or ribonucleoprotein complex assembly, thereby expanding the functional landscape of the m6A regulatory system. Dysregulation of m6A machinery can lead to multiple spermatogenic defects, including impaired SSC self-renewal, meiotic arrest, abnormal chromatin remodeling, and defective sperm formation, ultimately resulting in male infertility. Despite substantial advances, several critical questions remain unresolved, including the distinction between m6A-dependent and -independent mechanisms, the spatiotemporal dynamics of m6A modifications at single-cell resolution, and the coordination and antagonism among different regulatory factors. In this review, we systematically summarize the dual regulation of spermatogenesis by germ cell-intrinsic mechanisms and the testicular microenvironment, and delineate the molecular mechanisms and stage-specific functions of the dynamic m6A regulatory network. We further discuss the current limitations in the field and propose feasible experimental strategies for future investigation. Collectively, this work aims to provide a comprehensive framework for understanding the epitranscriptomic regulation of spermatogenesis and to offer theoretical insights into the pathogenesis and clinical management of male infertility.
5.The Diversity of Filamentous Morphologies and Magnetic Sensitivity Modulated by Diverse MagR Expression in Bacteria
Ya-Fei CHANG ; Jing ZHANG ; Peng ZHANG ; Xiu-Juan ZHOU ; Meng-Ke WEI ; Tian-Tian CAI ; Pei-Qi HE ; Jun-Feng WANG ; Can XIE
Progress in Biochemistry and Biophysics 2026;53(5):1439-1456
Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe2+), whereas clMagR favors ferric iron (Fe3+) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe2+-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe2+/Fe3+ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.
6.Clinical Efficacy of Modified Huangqi Chifengtang in Treatment of IgA Nephropathy Patients and Exploration of Dose-effect Relationship of Astragali Radix
Xiujie SHI ; Meiying CHANG ; Yue SHI ; Ziyan ZHANG ; Yifan ZHANG ; Qi ZHANG ; Hangyu DUAN ; Jing LIU ; Mingming ZHAO ; Yuan SI ; Yu ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(2):9-16
ObjectiveTo explore the dose-effect relationship and safety of high, medium, and low doses of raw Astragali Radix in the modified Huangqi Chifengtang (MHCD) for treating proteinuria in immunoglobulin A (IgA) nephropathy, and to provide scientific evidence for the clinical use of high-dose Astragali Radix in the treatment of proteinuria in IgA nephropathy. MethodsA total of 120 patients with IgA nephropathy, diagnosed with Qi deficiency and blood stasis combined with wind pathogen and heat toxicity, were randomly divided into a control group and three treatment groups. The control group received telmisartan combined with a Chinese medicine placebo, while the treatment groups were given telmisartan combined with MHCD containing different doses of raw Astragali Radix (60, 30, 15 g). Each group contained 30 patients, and the treatment period was 12 weeks. Changes in 24-hour urinary protein (24 hUTP), traditional Chinese medicine (TCM) syndrome scores, effective rate, and renal function were observed before and after treatment. Safety was assessed by monitoring liver function and blood routine. ResultsAfter 12 weeks of treatment, 24 hUTP significantly decreased in the high, medium, and low-dose groups, as well as the control group (P<0.05, P<0.01). The TCM syndrome scores in the high, medium, and low-dose groups also significantly decreased (P<0.01). Comparisons between groups showed that the 24 hUTP in the high-dose group was significantly lower than in the medium, low-dose, and control groups (P<0.05, P<0.01), and the 24 hUTP in the medium-dose group was significantly lower than in the control group (P<0.05). The TCM syndrome scores in the high and medium-dose groups were significantly lower than in the low-dose and control groups (P<0.05, P<0.01). The total effective rates for proteinuria in the high, medium, low-dose, and control groups were 92.59% (25/27), 85.19% (23/27), 60.71% (17/28), and 57.14% (16/28), respectively. The effective rates in the high and medium-dose groups were significantly higher than in the low-dose and control groups (χ2=13.185, P<0.05, P<0.01). The effective rates for TCM syndrome scores in the high, medium, low-dose, and control groups were 88.89% (24/27), 81.48% (22/27), 71.43% (20/28), and 46.43% (13/28), respectively. The efficacy of TCM syndrome scores in the high and medium-dose groups was significantly higher than in the control group (χ2=14.053, P<0.01). Compared with pre-treatment values, there was no statistically significant difference in eGFR and serum creatinine in the high and medium-dose groups. However, eGFR significantly decreased in the low-dose and control groups after treatment (P<0.05), and serum creatinine levels increased significantly in the control group (P<0.05). No statistically significant differences were observed in urea nitrogen, uric acid, albumin, total cholesterol, triglycerides, liver function, and blood routine before and after treatment in any group. ConclusionThere is a dose-effect relationship in the treatment of IgA nephropathy with high, medium, and low doses of raw Astragali Radix in MHCD. The high-dose group exhibited the best therapeutic effect and good safety profile.
7.Development of A High-performance Rectangular Ion Trap for Multi-reflection Time-of-Flight Mass Spectrometer
Xiao-Xia CHEN ; Yi REN ; Qi HUANG ; Da-Jun XIANG ; Chang-Wei LI ; Yi HONG ; Lei LI ; Zheng-Xu HUANG ; Mei LI ; Jing-Wei XU ; Zhen ZHOU
Chinese Journal of Analytical Chemistry 2025;53(1):38-46
As a new generation of time-of-flight mass spectrometry,multiple-reflection time-of-flight mass spectrometry(MR-TOF-MS)has been increasingly applied in the fields such as nuclear physics,chemistry,and biology due to its ultra-high resolution and rapid analysis capabilities.However,the analytical performance of MR-TOF-MS largely depends on the ion bunch state entering the mass analyzer.In this study,a rectangular ion trap(RIT)was developed,designed and processed using printed circuit board technology,as an ion accumulating and focusing device for MR-TOF mass analyzer.Compared to traditional ion traps composed of two sets of planar electrodes,this RIT had higher voltage utilization efficiency,resulting in more efficient ion collection and focusing.The ions were cooled to a sufficiently small bunch for precise mass measurement with MR-TOF-MS mass spectrometry in only 1 ms of cooling time in the RIT,then orthogonally ejected to the MR-TOF mass spectrometer for mass analysis.Experimental results indicated that the working cycle,ion flux,and ion focusing state of the RIT fully met the requirements of the MR-TOF mass analyzer.When coupled with the MR-TOF mass analyzer,the RIT enabled MR-TOF-MS to achieve a mass resolution of 1.5×105.
8.In Situ Analysis of Per-and Polyfluoroalkyl Substances Distribution Characteristics in Water-Sediment System Using Diffusive Gradients in Thin Films Probe
Qi-Si CAI ; Xing-Ying LI ; Fang ZHANG ; Jun-Wei YANG ; Si-Si LIU ; Chang-Er CHEN
Chinese Journal of Analytical Chemistry 2025;53(2):300-310,后插1-后插9
The water-sediment interface is an important zone for the migration and transformation of chemical substances,but traditional sampling methods make in situ sampling challenging,thus it is difficult to capture information on environmental processes at the micro-scale.In this study,diffusive gradients in thin films(DGT)probe technique was used as in situ tool to detect 18 kinds of typical per-and polyfluoroalkyl substances(PFAS)in the water-sediment system,elucidating their vertical distribution characteristics and patterns.The results showed that different PFAS exhibited distinct variation patterns with depth in water and sediment.Short-chain PFAS exhibited greater mobility,while the migration of long-chain PFAS was restricted in sediment and pore water due to their strong hydrophobicity and adsorption capacity,resulting in relatively small concentration changes in the sediment column.The PFAS concentrations measured by DGT ranged from 11.2 μg/L to 1305 μg/L.For long-chain PFAS,the concentrations measured by DGT were higher than those obtained from direct measurement of water and pore water,while the opposite results were obtained for short-chain PFAS.The DGT results indicated that although long-chain PFAS exhibited strong adsorption to sediment particles,the adsorbed PFAS were still bioavailable.DGT probe technique,with its advantages of in situ sampling and high spatial resolution,provides deep insights into the complex environmental processes occurring at the microscale in the water-sediment systems.DGT offers important technical support and scientific evidence for assessing the adsorption-desorption behavior,bioavailability,and ecological risks of these emerging pollutants in aquatic environment.
9.An RNA-cleaving DNAzyme and G-Quadruplex DNAzyme-Cascade System for Sensing of Small Molecules in Organic Cosolvent
Su-Hui LI ; Shuai-Qi ZHANG ; Yi-Bo ZHANG ; Quan ZHENG ; Tian-Jun CHANG
Chinese Journal of Analytical Chemistry 2025;53(6):914-923
Detection of poor-water-soluble substances typically requires an organic solvent containing solution,and therefore,the biosensors that can operate in such conditions are highly promising for practical applications.However,most existing biosensors have been developed in aqueous solution and it is hard to work effectively in organic solvent systems.In this work,we uncovered that the G-quadruplex(G4)/hemin DNAzyme(G4HD)could be strongly reactivated by NH4 in organic solvents at concentration up to 30%,and the activity was significantly higher than that in aqueous solutions containing K+.Based on this discovery,a biosensing system was developed for small molecule in 40%methanol by coupling G4HD with our previously identified RNA-cleaving DNAzyme(E3).This system comprised an ATP-activated aptazyme that was made of E3 and a G4HD that was activated by the cleavage product of the aptazyme.By using a manmade pipette tip filter to separate the reaction products,the subsequent colorimetric reaction of the G4HD could be triggered.This biosensing system enabled the visualization of target molecules in organic cosolvents without any other instruments.The activable DNAzyme-cascade sensing system had potential in point-of-care detection of poor-water-soluble pollutants,thereby enhancing the practical values of functional nucleic acid-based biosensors in real-world detection conditions.
10.Determination of Dilauryl Thiodipropionate in Fried Foods by Reverse Phase Liquid Chromatography-Tandem Mass Spectrometry
Jin-Can SHEN ; Yao LUO ; Feng-Qi WU ; Bei-Bei XIONG ; Zhang-Jie WU ; Ya-Mei LI ; Jun-Fa ZENG ; Chang-Xiong HUANG
Chinese Journal of Analytical Chemistry 2025;53(11):1860-1869
A method was developed for determination of dilauryl thiodipropionate(DLTDP)in fried foods by coupling solid-phase extraction(SPE)pretreatment with reverse-phase liquid chromatography-tandem mass spectrometry(RPLC-MS/MS)detection.Samples were extracted with n-hexane as the solvent,purified using a neutral alumina SPE cartridge,and finally analyzed by RPLC-MS/MS.Quantitative analysis was performed using matrix-matched calibration curves combined with an external standard method under optimal experimental conditions.The results showed that DLTDP exhibited good linearity in the range of 2.0-50.0 μg/L,with a correlation coefficient(R2)≥0.999.The limit of detection(LOD)and the limit of quantification(LOQ)of the method were 0.15 mg/kg and 0.5 mg/kg,respectively.The mean recoveries at three fortification levels(0.5,1.0,and 200 mg/kg)in different samples ranged from 84.8%to 96.8%,with the relative standard deviations(RSDs)all less than 8.0%.The developed method was highly sensitive,accurate and reliable,and easy to operate,making it well suited for the routine quantitative analysis of DLTDP in fried foods.

Result Analysis
Print
Save
E-mail