Discovery of a Highly Potent and Selective Inhibitor Targeting Protein Lysine Methyltransferase NSD2.

The histone lysine methyltransferase NSD2 has been recognized as an attractive target for cancer treatment, due to the functional implication of its dysregulation in the initiation and progression of many cancers. Although considerable efforts have been made to develop NSD2 small-molecule inhibitors, highly potent and selective ones are still rarely available till now. Here, we report the discovery of a series of novel NSD2 inhibitors via an extensive SAR exploration of the privileged quinazoline scaffold within compound 8. The most promising compound 42 showed excellent NSD2 enzymatic inhibitory activity and good antiproliferative activity in cells. In addition, it demonstrated favorable pharmacokinetic properties and significantly inhibited the tumor growth in a RS411 tumor xenograft model with good safety. Taken together, compound 42 could be a promising NSD2 inhibitor and deserves further investigation.

Rhodium(III) Complex Noncanonically Potentiates Antitumor Immune Responses by Inhibiting Wnt/ß-Catenin Signaling.

Metal-based chemoimmunotherapy has recently garnered significant attention for its capacity to stimulate tumor-specific immunity beyond direct cytotoxic effects. Such effects are usually caused by ICD via the activation of DAMP signals. However, metal complexes that can elicit antitumor immune responses other than ICD have not yet been described. Herein, we report that a rhodium complex (Rh-1) triggers potent antitumor immune responses by downregulating Wnt/ß-catenin signaling with subsequent activation of T lymphocyte infiltration to the tumor site. The results of mechanistic experiments suggest that ROS accumulation following Rh-1 treatment is a critical trigger of a decrease in ß-catenin and enhanced secretion of CCL4, a key mediator of T cell infiltration. Through these properties, Rh-1 exerts a synergistic effect in combination with PD-1 inhibitors against tumor growth in vivo. Taken together, our work describes a promising metal-based antitumor agent with a noncanonical mode of action to sensitize tumor tissues to ICB therapy.

Targeting undruggable phosphatase overcomes trastuzumab resistance by inhibiting multi-oncogenic kinases.

AIMS: Resistance to targeted therapy is one of the critical obstacles in cancer management. Resistance to trastuzumab frequently develops in the treatment for HER2+ cancers. The role of protein tyrosine phosphatases (PTPs) in trastuzumab resistance is not well understood. In this study, we aim to identify pivotal PTPs affecting trastuzumab resistance and devise a novel counteracting strategy. METHODS: Four public datasets were used to screen PTP candidates in relation to trastuzumab responsiveness in HER2+ breast cancer. Tyrosine kinase (TK) arrays were used to identify kinases that linked to protein tyrosine phosphate receptor type O (PTPRO)-enhanced trastuzumab sensitivity. The efficacy of small activating RNA (saRNA) in trastuzumab-conjugated silica nanoparticles was tested for PTPRO upregulation and resistance mitigation in cell models, a transgenic mouse model, and human cancer cell line-derived xenograft models. RESULTS: PTPRO was identified as the key PTP which influences trastuzumab responsiveness and patient survival. PTPRO de-phosphorated several TKs, including the previously overlooked substrate ERBB3, thereby inhibiting multiple oncogenic pathways associated with drug resistance. Notably, PTPRO, previously deemed "undruggable," was effectively upregulated by saRNA-loaded nanoparticles. The upregulated PTPRO simultaneously inhibited ERBB3, ERBB2, and downstream SRC signaling pathways, thereby counteracting trastuzumab resistance. CONCLUSIONS: Antibody-conjugated saRNA represents an innovative approach for targeting "undruggable" PTPs.

Meta-analysis of the accuracy for RASSF1A methylation in bronchial aspirates for the diagnosis of lung cancer.

OBJECTIVE: To establish the diagnostic accuracy of RASSF1A (Ras association domain family 1 isoform) methylation using bronchial aspirates as an auxiliary method for diagnosing lung cancer through a systematic review and meta-analysis. METHODS: Studies published prior to October 30, 2022, were retrieved from the Embase, PubMed, Web of Science, and Wan Fang databases using the keywords "lung cancer", "RASSF1A", "methylation", and "bronchial aspirates". A fixed or random effect model was used to calculate the combined sensitivity, specificity, positive likelihood ratios (LR), negative LR, diagnostic odds ratio (DOR), along with the respective 95% confidence intervals (CIs) and the area under the curve (AUC) with Q index. The threshold effect was defined by using the Spearman correlation coefficient, and the Deeks funnel plot was generated to evaluate publication bias. RESULTS: Among the 12 trials that met the inclusion criteria, a total of 2388 participants were involved. The pooled results for the diagnosis of lung cancer were as follows, when compared to the pathological diagnosis: sensitivity of 0.47 (95% CI: 0.45-0.50), specificity of 0.96 (95% CI: 0.95-0.97), positive LR of 12.18 (95% CI: 8.96-16.55), negative LR of 0.56 (95% CI: 0.52-0.61), DOR of 24.05 (95% CI: 17.29-33.47), and AUC of 0.78 (Q index = 0.72), respectively. The sensitivity of the RASSF1A methylation assay was relatively low in a detailed subgroup analysis, fluctuating between 0.39 and 0.90, indicating a limitation in its diagnostic value for lung cancer. The RASSF1A methylation assay, on the other hand, demonstrated excellent specificity, suggesting a high exclusion value. Of note, the diagnostic sensitivity, specificity, DOR, and AUC for small cell lung cancer were 0.90 (0.84-0.94), 0.95 (0.94-0.97), 249.5 (103.94-598.8), and 0.98, respectively, showing that RASSF1A methylation was a promising biomarker for diagnosing small cell lung cancer with both high diagnostic and exclusion value. Furthermore, RASSF1A methylation using bronchial washings and bronchial aspirates showed a high AUC of 0.998 and 0.93, respectively, indicating excellent diagnostic performance. CONCLUSIONS: The methylation of RASSF1A in bronchial aspirates demonstrated a high level of diagnostic accuracy and has the potential to be a valuable supplementary diagnostic method, especially for identifying small cell lung cancer.

Dahuang Zhechong Pill Alleviates Liver Fibrosis Progression by Regulating p38 MAPK/NF-κ B/TGF-ß1 Pathway.

OBJECTIVE: To explore the effect and mechanism of Dahuang Zhechong Pill (DHZCP) on liver fibrosis. METHODS: Liver fibrosis cell model was induced by transforming growth factor-ß (TGF-ß) in hepatic stellate cells (HSC-T6). DHZCP medicated serum (DMS) was prepared in rats. HSC-T6 cells were divided into the control (15% normal blank serum culture), TGF-ß (15% normal blank serum + 5 ng/mL TGF-ß), DHZCP (15% DMS + 5 ng/mL TGF-ß), DHZCP+PDTC [15% DMS + 4 mmol/L ammonium pyrrolidine dithiocarbamate (PDTC)+ 5 ng/mL TGF-ß], and PDTC groups (4 mmol/L PDTC + 5 ng/mL TGF-ß). Cell activity was detected by cell counting kit 8 and levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1ß, IL-6, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the cell supernatant were determined by enzyme-linked immunosorbnent assay. Western blot was used to measure the expressions of p38 mitogen-activated protein kinase/nuclear factor kappa B/transforming growth factor-ß1 (p38 MAPK/NF-κ B/TGF-ß1) pathway related proteins, and the localization and expressions of these proteins were observed by immunofluorescence staining. RESULTS: DHZCP improves the viability of cells damaged by TGF-ß and reduces inflammatory cytokines and ALT and AST levels in the supernatant of HSC-T6 cells induced with TGF-ß (P<0.05 or P<0.01). Compared with the TGF-ß group, NF-κ B p65 levels in the DHZCP group were decreased (P<0.05). p38 MAPK and NF-κ B p65 levels in the DHZCP+PDTC were also reduced (P<0.01). Compared with the TGF-ß group, the protein expression of Smad2 showed a downward trend in the DHZCP, DHZCP+PDTC, and PDTC groups (all P<0.01), and the decreasing trend of Samd3 was statistically significant only in DHZCP+PDTC group (P<0.01), whereas Smad7 was increased (P<0.05 or P<0.01). CONCLUSION: DHZCP can inhibit the process of HSC-T6 cell fibrosis by down-regulating the expression of p38 MAPK/NF-κ B/TGF-ß1 pathway.

Construction of Dual-Active Sites by Interfacing with Polyhydroxy Fullerene on Nickel Hydroxide Surfaces to Promote CO2 Deep Photoreduction to CH4.

Due to the complex series of elementary steps involved, achieving deep photoreduction of CO2 to multielectron products such as CH4 remains a challenging task. Therefore, it is crucial to strategically design catalysts that facilitate the controlled formation of the crucial intermediates and provide precise control over the reaction pathway. Herein, we present a pioneering approach by employing polyhydroxy fullerene (PHF) molecules to modify the surface of Ni(OH)2, creating stable and effective synergistic sites to enhance the formation of CH4 from CO2 under light irradiation. As a result, the optimized PHF-modified Ni(OH)2 cocatalyst achieves a CH4 production rate of 455 µmol g-1 h-1, with an electron-based selectivity of approximately 60%. The combination of in situ characterizations and theoretical calculations reveals that the hydroxyl species on the surface of PHF can participate in stabilizing crucial intermediates and facilitating water activation, thereby altering the reaction pathway to form CH4 instead of CO. This study provides a novel approach to regulating the selectivity of photocatalytic CO2 reduction by exploring molecular surface modification through interfacing with functionalized carbon clusters.

Discovery of the First-in-Class RORγ Covalent Inhibitors for Treatment of Castration-Resistant Prostate Cancer.

Nuclear receptor receptor-related orphan receptor γ (RORγ) is a ligand-dependent transcription factor and has been established as a key player in castration-resistant prostate cancers (CRPC) by driving androgen receptor (AR) overexpression, representing a potential therapeutical target for advanced prostate cancers. Here, we report the identification of the first-in-class RORγ covalent inhibitor 29 via the structure-based drug design approach following structure-activity relationship (SAR) exploration. Mass spectrometry assay validated its covalent inhibition mechanism. Compound 29 significantly inhibited RORγ transcriptional activity and remarkably suppressed the expression levels of AR and AR-targeted genes. Compound 29 also exhibited much superior activity in inhibiting the proliferation and colony formation and inducing apoptosis of the CRPC cell lines relative to the positive control 2 and noncovalent control 33. Importantly, it markedly suppressed the tumor growth in a 22Rv1 mouse tumor xenograft model with good safety. These results clearly demonstrate that 29 is a highly potent and selective RORγ covalent inhibitor.

DZ2002 alleviates corneal angiogenesis and inflammation in rodent models of dry eye disease via regulating STAT3-PI3K-Akt-NF-κB pathway.

Dry eye disease (DED) is a prevalent ocular disorder with a multifactorial etiology. The pre-angiogenic and pre-inflammatory milieu of the ocular surface plays a critical role in its pathogenesis. DZ2002 is a reversible type III S-adenosyl-L-homocysteine hydrolase (SAHH) inhibitor, which has shown excellent anti-inflammatory and immunosuppressive activities in vivo and in vitro. In this study, we evaluated the therapeutic potential of DZ2002 in rodent models of DED. SCOP-induced dry eye models were established in female rats and mice, while BAC-induced dry eye model was established in female rats. DZ2002 was administered as eye drops (0.25%, 1%) four times daily (20 µL per eye) for 7 or 14 consecutive days. We showed that topical application of DZ2002 concentration-dependently reduced corneal neovascularization and corneal opacity, as well as alleviated conjunctival irritation in both DED models. Furthermore, we observed that DZ2002 treatment decreased the expression of genes associated with angiogenesis and the levels of inflammation in the cornea and conjunctiva. Moreover, DZ2002 treatment in the BAC-induced DED model abolished the activation of the STAT3-PI3K-Akt-NF-κB pathways in corneal tissues. We also found that DZ2002 significantly inhibited the proliferation, migration, and tube formation of human umbilical endothelial cells (HUVECs) while downregulating the activation of the STAT3-PI3K-Akt-NF-κB pathway. These results suggest that DZ2002 exerts a therapeutic effect on corneal angiogenesis in DED, potentially by preventing the upregulation of the STAT3-PI3K-Akt-NF-κB pathways. Collectively, DZ2002 is a promising candidate for ophthalmic therapy, particularly in treating DED.

Reversible SAHH inhibitor ameliorates MIA-induced osteoarthritis of rats through suppressing MEK/ERK pathway.

Osteoarthritis (OA) is characterized by gradual articular cartilage degradation, accompanied by persistent low-grade joint inflammation, correlating with radiographic and pain-related progression. The latent therapeutic potential of DZ2002, a reversible inhibitor of S-adenosyl-L-homocysteine hydrolase (SAHH), holds promise for OA intervention. This study endeavored to examine the therapeutic efficacy of DZ2002 within the milieu of OA. The cytotoxicity of DZ2002 was evaluated using the MTT assay on bone marrow-derived macrophages. The inhibitory impact of DZ2002 during the process of osteoclastogenesis was assessed using TRAP staining, analysis of bone resorption pits, and F-actin ring formation. Mechanistic insights were derived from qPCR and Western blot analyses. Through the intra-articular injection of monosodium iodoacetate (MIA), an experimental rat model of OA was successfully instituted. This was subsequently accompanied by a series of assessments including Von Frey filament testing, analysis of weight-bearing behaviors, and micro-CT imaging, all aimed at assessing the effectiveness of DZ2002. The findings emphasized the effectiveness of DZ2002 in mitigating osteoclastogenesis induced by M-CSF/RANKL, evident through a reduction in TRAP-positive OCs and bone resorption. Moreover, DZ2002 modulated bone resorption-associated gene and protein expression (CTSK, CTR, Integrin ß3) via the MEK/ERK pathway. Encouragingly, DZ2002 also alleviates MIA-induced pain, cartilage degradation, and bone loss. In conclusion, DZ2002 emerges as a potential therapeutic contender for OA, as evidenced by its capacity to hinder in vitro M-CSF/RANKL-induced osteoclastogenesis and mitigate in vivo osteoarthritis progression. This newfound perspective provides substantial support for considering DZ2002 as a compelling agent for osteoarthritis intervention.

Design, synthesis and evaluation of quinazoline derivatives as Gαq/11 proteins inhibitors against uveal melanoma.

Uveal melanoma (UM) represents the predominant ocular malignancy among adults, exhibiting high malignancy and proclivity for liver metastasis. GNAQ and GNA11 encoding Gαq and Gα11 proteins are key genes to drive UM, making the selective inhibition of Gαq/11 proteins to be a potential therapeutic approach for combating UM. In this study, forty-six quinazoline derivatives were designed, synthesized, and assessed for their ability to inhibit Gαq/11 proteins and UM cells. Compound F33 emerged as the most favorable candidate, and displayed moderate inhibitory activity against Gαq/11 proteins (IC50 = 9.4 µM) and two UM cell lines MP41 (IC50 = 6.7 µM) and 92.1 (IC50 = 3.7 µM). Being a small molecule inhibitor of Gαq/11 proteins, F33 could effectively suppress the activation of downstream signaling pathways in a dose-dependent manner, and significantly inhibits UM in vitro.F33 represents a promising lead compound for developing therapeutics for UM by targeting Gαq/11 proteins.

Eccrine Poroma with Concurrent Basal Cell Carcinoma: A Rare Combination.

Eccrine poroma (EP) is a benign skin appendicular tumor that differentiates into the terminal sweat duct and is often differentiated from basal cell carcinoma (BCC) and seborrheic keratosis. This report describes a 58-year-old woman who presented with left occipital plaque. Histopathological analysis showed that the tumor cells were located in the lower part of the epidermis. The tumor cells were cuboidal or circular basal-like cells of the same size. The surrounding cells were not arranged in a palisade shape. Scattered tumor clusters composed of basal-like cells were also seen in the dermis, staining basophilic, and the surrounding cells were arranged in a palisade pattern. Immunohistochemistry showed that BerEP4, epithelial membrane antigen EMA, carcinoembryonic antigen CEA, Bcl-2, CD10, CK7 were positive, AR, PAS were negative. According to the pathological examination and immunohistochemical results, a case of eccrine poroma with concurrent basal cell carcinoma was diagnosed.

Discovery of novel indazole derivatives as SOS1 agonists that activate KRAS signaling.

KRAS serves as a vital regulator for cellular signaling and drives tumor pathogenesis after mutation. Despite extensive research efforts spanning several decades, targeting KRAS is still challenging due to the multiple KRAS mutations and the emergence of drug resistance. Interfering the interactions between KRAS and SOS1 is one of the promising approaches for modulating KRAS functions. Herein, we discovered small-molecule SOS1 agonists with novel indazole scaffold. Through structure-based optimization, compound 11 was identified with high SOS1 activation potency (p-ERK EC50 = 1.53 µM). In HeLa cells, compound 11 enhances cellular RAS-GTP levels and exhibits biphasic modulation of ERK1/2 phosphorylation through an on-target mechanism and presents the therapeutic potential to modulate RAS signaling by activating SOS1.

Bispecific antibody CD73xEGFR more selectively inhibits the CD73/adenosine immune checkpoint on cancer cells and concurrently counteracts pro-oncogenic activities of CD73 and EGFR.

BACKGROUND: CD73 is an ecto-enzyme that is involved in the conversion of pro-inflammatory extracellular ATP (eATP) excreted by cancer cells under stress to anti-inflammatory adenosine (ADO). A broad variety of solid cancer types was shown to exploit CD73 overexpression as a suppressive immune checkpoint. Consequently, CD73-antagonistic antibodies, most notably oleclumab, are currently evaluated in several multicenter trials for clinical applicability. However, the efficacy of conventional monospecific CD73-inhibiting antibodies may be limited due to on-target/off-tumor binding to CD73 on normal cells. Therefore, a novel approach that more selectively directs CD73 immune checkpoint inhibition towards cancer cells is warranted. METHODS: To address this issue, we constructed a novel tetravalent bispecific antibody (bsAb), designated bsAb CD73xEGFR. Subsequently, the anticancer activities of bsAb CD73xEGFR were evaluated using in vitro and in vivo tumor models. RESULTS: In vitro treatment of various carcinoma cell types with bsAb CD73xEGFR potently inhibited the enzyme activity of CD73 (~71%) in an EGFR-directed manner. In this process, bsAb CD73xEGFR induced rapid internalization of antigen/antibody complexes, which resulted in a prolonged concurrent displacement of both CD73 and EGFR from the cancer cell surface. In addition, bsAb CD73xEGFR sensitized cancer to the cytotoxic activity of various chemotherapeutic agents and potently inhibited the proliferative/migratory capacity (~40%) of cancer cells. Unexpectedly, we uncovered that treatment of carcinoma cells with oleclumab appeared to enhance several pro-oncogenic features, including upregulation and phosphorylation of EGFR, tumor cell proliferation (~20%), and resistance towards cytotoxic agents and ionizing radiation (~39%). Importantly, in a tumor model using immunocompetent BALB/c mice inoculated with syngeneic CD73pos/EGFRpos CT26 cancer cells, treatment with bsAb CD73xEGFR outperformed oleclumab (65% vs 31% tumor volume reduction). Compared with oleclumab, treatment with bsAb CD73xEGFR enhanced the intratumoral presence of CD8pos T cells and M1 macrophages. CONCLUSIONS: BsAb CD73xEGFR outperforms oleclumab as it inhibits the CD73/ADO immune checkpoint in an EGFR-directed manner and concurrently counteracts several oncogenic activities of EGFR and CD73. Therefore, bsAb CD73xEGFR may be of significant clinical potential for various forms of difficult-to-treat solid cancer types.

Indocyanine green-based fluorescence imaging improved by deep learning.

Intraoperative identification of malignancies using indocyanine green (ICG)-based fluorescence imaging could provide real-time guidance for surgeons. Existing ICG-based fluorescence imaging mostly operates in the near-infrared (NIR)-I (700-1000 nm) or the NIR-IIa' windows (1000-1300 nm), which is not optimal in terms of spatial resolution and contrast as their light scattering is higher than the NIR-IIb window (1500-1700 nm). It is highly desired to achieve ICG-based fluorescence imaging in the NIR-IIb window, but it is hindered by its ultra-low NIR-IIb emission tail of ICG. Herein, we employ a generative adversarial network to generate NIR-IIb ICG images directly from the acquired NIR-I ICG images. This approach was investigated by in vivo imaging of sub-surface vascular, intestine structure, and tumors, and their results demonstrated significant improvement in spatial resolution and contrast for ICG-based fluorescence imaging. It is potential for deep learning to improve ICG-based fluorescence imaging in clinical diagnostics and image-guided surgery in clinics.

Novel acridine-based LSD1 inhibitors enhance immune response in gastric cancer.

Recently, histone lysine specific demethylase 1 (LSD1) has become an emerging and promising target for cancer immunotherapy. Herein, based on our previously reported LSD1 inhibitor DXJ-1 (also called 6x), a series of novel acridine-based LSD1 inhibitors were identified via structure optimizations. Among them, compound 5ac demonstrated significantly enhanced inhibitory activity against LSD1 with an IC50 value of 13 nM, about 4.6-fold more potent than DXJ-1 (IC50 = 73 nM). Molecular docking studies revealed that compound 5ac could dock well into the active site of LSD1. Further mechanism studies showed that compound 5ac inhibited the stemness and migration of gastric cancer cells, and reduced the expression of PD-L1 in BGC-823 and MFC cells. More importantly, BGC-823 cells were more sensitive to T cell killing when treated with compound 5ac. Besides, the tumor growth was also suppressed by compound 5ac in mice. Together, 5ac could serve as a promising candidate to enhance immune response in gastric cancer.

Salivary Extracellular MicroRNAs for Early Detection and Prognostication of Esophageal Cancer: A Clinical Study.

BACKGROUND & AIMS: Early detection of esophageal squamous cell carcinoma (ESCC) will facilitate curative treatment. We aimed to establish a microRNA (miRNA) signature derived from salivary extracellular vesicles and particles (EVPs) for early ESCC detection and prognostication. METHODS: Salivary EVP miRNA expression was profiled in a pilot cohort (n = 54) using microarray. Area under the receiver operator characteristic curve (AUROC) and least absolute shrinkage and selector operation regression analyses were used to prioritize miRNAs that discriminated patients with ESCC from controls. Using quantitative reverse transcription polymerase chain reaction, the candidates were measured in a discovery cohort (n = 72) and cell lines. The prediction models for the biomarkers were derived from a training cohort (n = 342) and validated in an internal cohort (n = 207) and an external cohort (n = 226). RESULTS: The microarray analysis identified 7 miRNAs for distinguishing patients with ESCC from control subjects. Because 1 was not always detectable in the discovery cohort and cell lines, the other 6 miRNAs formed a panel. A signature of this panel accurately identified patients with all-stage ESCC in the training cohort (AUROC = 0.968) and was successfully validated in 2 independent cohorts. Importantly, this signature could distinguish patients with early-stage (stage Ⅰ/Ⅱ) ESCC from control subjects in the training cohort (AUROC = 0.969, sensitivity = 92.00%, specificity = 89.17%) and internal (sensitivity = 90.32%, specificity = 91.04%) and external (sensitivity = 91.07%, specificity = 88.06%) validation cohorts. Moreover, a prognostic signature based on the panel was established and efficiently predicted the high-risk cases with poor progression-free survival and overall survival. CONCLUSIONS: The salivary EVP-based 6-miRNA signature can serve as noninvasive biomarkers for early detection and risk stratification of ESCC. Chinese Clinical Trial Registry, ChiCTR2000031507.

Scalable and Depurative Zirconium Metal-Organic Framework for Deep Flue-Gas Desulfurization and SO2 Recovery.

Deep SO2 removal and recovery as industrial feedstock are of importance in flue-gas desulfurization and natural-gas purification, yet developing low-cost and scalable physisorbents with high efficiency and recyclability remains a challenge. Herein, we develop a viable synthetic protocol to produce DUT-67 with a controllable MOF structure, excellent crystallinity, adjustable shape/size, milli-to-kilogram scale, and consecutive production by recycling the solvent/modulator. Furthermore, simple HCl post-treatment affords depurated DUT-67-HCl featuring ultrahigh purity, excellent chemical stability, fully reversible SO2 uptake, high separation selectivity (SO2/CO2 and SO2/N2), greatly enhanced SO2 capture capacity, and good reusability. The SO2 binding mechanism has been elucidated by in situ X-ray diffraction/infrared spectroscopy and DFT/GCMC calculations. The single-step SO2 separation from a real quaternary N2/CO2/O2/SO2 flue gas containing trace SO2 is implementable under dry and 50% humid conditions, thus recovering 96% purity. This work may pave the way for future SO2 capture-and-recovery technology by pushing MOF syntheses toward economic cost, scale-up production, and improved physiochemical properties.

"UV-Driven Self-Cleaning" Magnetic Molecularly Imprinted Absorbents Coupled with LTP-MS and LC-TQ-MS for Rapid High-Throughput Screening and Quantification of Organophosphorus Pesticides in Agro-products.

Organophosphorus magnetic molecularly imprinted polymers (OMMIPs) with high adsorption capacities (13.5-83.8 mg g-1) and good applicability were developed for efficient extraction and pre-concentration of multiple organophosphorus pesticides (OPPs) from foodstuffs. The OMMIP-based sample pretreatment coupled with low-temperature plasma ambient ionization mass spectrometry achieved rapid screening for 90 kinds of pesticides at default maximum residue limits of National Standard (GB 2763-2021) in nine types of agro-products. The OMMIP-based liquid chromatography coupled with triple quadrupole mass spectroscopy assay demonstrated rapid magneto-actuated isolation, efficient removal of matrix interference, and reduced signal suppression, resulting in a short detection time (30 min), compliant recoveries (60.1-127.5%), low detection limits (0.0001-0.073 µg g-1), and simultaneous quantification of multi-pesticides. The yolk-shell-structured OMMIPs (Fe3O4@mTiO2@MIPs) demonstrated additional benefits of excellent ultraviolet light-driven catalytic degradation activity toward OPPs, making them eco-friendly for self-cleaning regeneration and reducing laboratory pesticide discharge. This work highlights the potential of OMMIPs for high-throughput and in situ pesticide monitoring in modern large-scale agricultural markets.