{
  "abstract": "Background Necrotizing enterocolitis (NEC) remains a leading cause of mortality in preterm infants, with an insidious onset and rapid progression. Current diagnostic approaches primarily identify late-stage structural damage, such as pneumatosis intestinalis, missing the critical early molecular phase. Hypochlorous acid (HClO), generated via the MPO–H 2O2–Cl− system in activated neutrophils, serves as an early oxidative stress biomarker in NEC. This study aims to evaluate a newly developed dual-modal near-infrared fluorescence and photoacoustic probe, GSS-CO2, for real-time, in vivo detection of intestinal HClO to enable earlier diagnosis (IDDF2026-ABS-0451 Figure 1. Reaction mechanism of GSS-CO2 with HCLO generating fluorescence and photoacoustic signals).Methods GSS-CO 2 was synthesized and characterized by NMR and HR-MS. Its responsiveness to HClO was assessed by UV–vis absorption, fluorescence spectroscopy, and photoacoustic (PA) imaging in vitro. Cellular HClO detection was evaluated in IEC-6 intestinal epithelial cells under exogenous and lipopolysaccharide (LPS)-induced endogenous conditions. In vivo performance was investigated in a neonatal rat NEC model following enema or intraperitoneal administration of GSS-CO2. Fluorescence imaging was performed at multiple time points (0–120 min), and PA imaging was conducted to assess deep-tissue lesion localization. Biosafety was evaluated by H&E staining of major organs.Results Upon HClO activation, GSS-CO 2 exhibited a significant near-infrared fluorescence turn-on at 780 nm under 685 nm excitation, along with a distinct PA signal at 710 nm. In IEC-6 cells, the probe effectively detected both exogenous and LPS-induced endogenous HClO with minimal background fluorescence. In NEC rats, strong fluorescence signals were observed immediately after probe administration, peaking at 30 min (enema) or 60 min (intraperitoneal) and diminishing by 120 min, whereas control rats showed no significant signal. PA imaging further revealed robust signal enhancement in the intestinal region of NEC rats, enabling precise localization of inflamed tissue (IDDF2026-ABS-0451 Figure 2. (A) Linear correlation between PA intensity of GSS-CO2 and NaClO concentration; inset: PA images. (B) Fluorescence imaging in cells. (C) In vivo fluorescence and (D) photoacoustic imaging of HClO in NEC rats after GSS-CO2 administration). H&E staining confirmed no probe-related toxicity in major organs.Conclusions GSS-CO 2 enables rapid, sensitive, and dual-modal imaging of intestinal HClO in vivo, combining the high molecular sensitivity of fluorescence with the deep-tissue resolution of photoacoustic imaging. This dual-signal strategy reduces false-positive risks and allows concurrent visualization of molecular inflammation and structural damage. These findings support the potential of GSS-CO2 as a promising imaging tool for early NEC diagnosis and image-guided intervention.Abstract IDDF2026-ABS-0451 Figure 1Abstract IDDF2026-ABS-0451 Figure 2",
  "authors": [
    {
      "affiliations": [
        "Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child and Adolescent Health, Zhejiang Key Laboratory of Neonatal Diseases, China"
      ],
      "name": "Lijia Wang"
    },
    {
      "affiliations": [
        "Department of Thoracic Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, China"
      ],
      "name": "Boyou Zhang"
    },
    {
      "affiliations": [
        "Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child and Adolescent Health, Zhejiang Key Laboratory of Neonatal Diseases, China"
      ],
      "name": "Yongjie Liu"
    },
    {
      "affiliations": [
        "Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child and Adolescent Health, Zhejiang Key Laboratory of Neonatal Diseases, China"
      ],
      "name": "Mingming Zhou"
    },
    {
      "affiliations": [
        "Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child and Adolescent Health, Zhejiang Key Laboratory of Neonatal Diseases, China"
      ],
      "name": "Zefeng Zheng"
    },
    {
      "affiliations": [
        "Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child and Adolescent Health, Zhejiang Key Laboratory of Neonatal Diseases, China"
      ],
      "name": "Qiang Shu"
    },
    {
      "affiliations": [
        "College of Chemistry and Materials Science, Hengyang Normal University, China"
      ],
      "name": "Biao Gu"
    }
  ],
  "title": "IDDF2026-ABS-0451 Early diagnosis of necrotizing enterocolitis using a novel dual-modal nir fluorescence and photoacoustic probe activated by HCLO",
  "uid": "ed7483de-2b56-5472-b58d-d7aa2c6e2342"
}