Drug Delivery and Translational Research最新文献

{"title":"Imaging of intranasal drug delivery to the brain: updated review 2.0.","authors":"Hannah E Beaven, Marina R Schinker, Thura Tun Oo, Kylie R Smith, Mosa Alhamami, Michael C Veronesi","doi":"10.1007/s13346-026-02204-8","DOIUrl":"https://doi.org/10.1007/s13346-026-02204-8","url":null,"abstract":"<p><p>Since the first review on imaging of intranasal drug delivery (INDD) was published in 2020, interest in the topic has increased, necessitating an update, which is the basis of the current review. INDD is a promising alternative for treating central nervous system (CNS) diseases. In vivo imaging is also important for therapy assessment, both clinically and preclinically. This review details studies that further our understanding of INDD and the fate of these therapies in the CNS using in vivo imaging. We performed a literature search using the keywords \"Intranasal delivery\" and \"Imaging\" from 2020 to 2025 and summarized these findings in the current updated review. This review is not comprehensive but provides examples of recent publications that explore the various treatments under development for nose-to-brain (N2B) therapeutic delivery through imaging. Imaging will include magnetic resonance imaging (MRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), gamma scintigraphy, and computed tomography (CT) for both humans and animals. Additional specialty topics pursued experimentally in animals include in vivo optical imaging techniques, including bioluminescence and fluorescence imaging. Finally, we discuss image-guided therapeutic techniques such as focused ultrasound and conclude with future directions. In this review, we introduce each imaging modality, describe its utilization, and outline its strengths and weaknesses, specifically in the context of N2B therapeutics.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148789452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Endothelial progenitor cells-derived exosomes reduce ferroptosis and promote neovascularization after intracranial atherosclerosis in association with the NCOA4/FTH1 cascade modulation.","authors":"Lihong Zhang, Cui Wang, Zhanjun Wu, Hong Qu, Jitong Ma, Di Li","doi":"10.1007/s13346-026-02198-3","DOIUrl":"https://doi.org/10.1007/s13346-026-02198-3","url":null,"abstract":"<p><p>Intracranial atherosclerosis (ICAS) is a leading cause of ischemic stroke. This study explored the mechanism of endothelial progenitor cells-derived exosomes (EPCs-exos) in ICAS. Rat EPCs were isolated, EPCs-exos were extracted and identified. A rat model of ICAS was established, and EPCs and EPCs-exos or lentiviral si-NCOA4 were injected into rats to observe the histopathological changes in cerebral microvessels, ferroptosis, angiogenesis, inflammatory indexes, and the NCOA4/FTH1 pathway. Hematoxylin and eosin staining was performed to observe the histopathology of cerebral microvascular tissue. EPCs were successfully isolated from rats and EPCs-exos were identified. EPC treatment inhibited the NCOA4/FTH1 pathway, hindered inflammatory responses and ferroptosis in ICAS rats, promoted neovascularization, and improved histopathology. EPCs-exos similarly reduced inflammatory responses and ferroptosis and promoted neovascularization in ICAS rats. In conclusion, EPCs‑exos reduce ferroptosis, attenuate inflammatory responses, and enhance cerebral neovascularization in ICAS rats in association with the NCOA4/FTH1 pathway modulation.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148758163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Repositioning pentoxifylline via inhalable novasomes for pulmonary fibrosis: from statistical optimization to in-vivo evaluation.","authors":"Mohamed Mahmoud Ali, Nesma Ahmed Shiha, Raguia Aly Shoukri, Carol Yousry","doi":"10.1007/s13346-026-02200-y","DOIUrl":"https://doi.org/10.1007/s13346-026-02200-y","url":null,"abstract":"<p><p>Pulmonary fibrosis (PF) represents the final stage of lung injuries, triggered mainly by viral infections. Pentoxifylline (PTX) is a hemorheologic drug that has been recently repurposed for the prophylaxis of PF. Nevertheless, it exhibits low oral bioavailability. This study aims to develop inhalable PTX-loaded novasomes with enhanced pulmonary deposition and improved therapeutic efficiency. PTX-novasomal nanovesicles were prepared using ethanol injection technique and characterized for particle size, zeta potential, and entrapment efficiency, adopting a central composite statistical design for optimization. The optimized PTX-novasomes were subsequently evaluated for in-vitro drug release and aerodynamic size characterization using Andersen Cascade Impactor. Furthermore, the optimized PTX-novasomes were characterized using transmission electron microscopy, Fourier-transform infrared spectroscopy, and differential scanning calorimetry. Finally, an in-vivo pharmacodynamic study was performed in a bleomycin-induced PF rat model to assess the effects of inhaled PTX-novasomes on the inflammatory and fibrotic biomarkers, and fibrosis scoring via Masson's trichrome stain. Results showed that the optimized Novasomes were successfully prepared as spheroidal nanosized vesicles (239.80 nm) with high PTX encapsulation (59.22%), and a biphasic release profile. Moreover, the optimized novasomes demonstrated significantly higher fine particle fraction (43.819%) and smaller mass median aerodynamic diameter (1.612 μm) than free PTX. Furthermore, the in-vivo studies revealed a marked reduction in the levels of inflammatory and fibrotic biomarkers following inhalation of PTX-novasomes, outperforming the conventional oral formulation. These findings signify the impact of integrating novasomal formulation with inhalational delivery in enhancing aerodynamic performance and pulmonary deposition of PTX, supporting the potential repositioning of PTX inhalable novasomes for PF prophylaxis.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148762032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Advances in stimuli-responsive hydrogels for liver disease therapy: mechanisms, applications, and translational perspectives.","authors":"Yilin Kuang, Yuhang Li, Chang Xu, Jinyan Chen, Huigang Li, Chenghao Cao, Peiru Zhang, Zhu Li, Rongsen Wang, Jinxin Xu, Hantian Yin, Jianyong Zhuo, Xiao Xu, Di Lu","doi":"10.1007/s13346-026-02201-x","DOIUrl":"https://doi.org/10.1007/s13346-026-02201-x","url":null,"abstract":"<p><p>The liver is a pivotal organ for metabolic and immune homeostasis, playing an essential role in maintaining physiological balance. Globally, the increasing incidence and mortality of liver diseases constitute a critical public health issue. However, conventional therapies are often limited by their inability to precisely target the pathological microenvironment of the liver, frequently resulting in either insufficient efficacy or excessive tissue damage. With notable biocompatibility, a tunable porous architecture, and smart responsive capabilities, hydrogels hold considerable promise as drug carriers for treating liver diseases. This review evaluates the core design principles and therapeutic value of stimuli-responsive hydrogels in liver disease, compares hydrogel systems, details their responsive modes, and highlights recent progress in antitumor, antioxidant, anti-fibrotic, and immunomodulatory therapy. Ultimately, the present review examines the key challenges and future directions for translating stimuli-responsive hydrogels into more precise, safe, and personalized therapies for liver diseases.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148697262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Brain-targeted intranasal aripiprazole via modified chitosan nanoparticles: controlled release, pharmacokinetics, and pharmacodynamics.","authors":"Rabab M Ibrahim, Mahmoud H Teaima, Mohamed A El-Nabarawi, Noha M Badawi","doi":"10.1007/s13346-026-02193-8","DOIUrl":"https://doi.org/10.1007/s13346-026-02193-8","url":null,"abstract":"<p><p>Schizophrenia remains one of the most disabling mental disorders, and effective therapy is still limited by the difficulty of delivering drugs across the blood-brain barrier. Aripiprazole (Ari), a first-line atypical antipsychotic, exhibits restricted clinical performance due to poor solubility, extensive hepatic metabolism, and limited brain exposure. Herein, a novel intranasal nanocarrier system was developed to enable direct and sustained delivery of Ari to the brain. Chitosan nanoparticles (Cs-NPs) surface-modified with sodium dodecyl sulfate (SDS) were prepared by the ionic gelation method and optimized using a Box-Behnken design to evaluate the effects of SDS concentration, pH, and chitosan-to-tripolyphosphate ratio on particle size, zeta potential, and drug entrapment. The optimized formulation showed a mean particle size of ~ 200 nm, a positive surface charge, and an entrapment efficiency of 76.98 ± 7.6%. Transmission electron microscopy confirmed spherical morphology, while the in vitro release profile exhibited an initial burst followed by a sustained phase, indicating controlled-release behavior. Pharmacokinetic evaluation using LC-MS/MS revealed significantly enhanced Ari bioavailability and brain uptake following intranasal administration of the optimized Cs-NPs compared with oral, intravenous, and intranasal solutions. Pharmacodynamic testing in a ketamine-induced psychosis rat model (open-field and forced-swim tests) demonstrated improved antipsychotic efficacy. Neurochemical analysis showed restoration of dopamine and γ-aminobutyric acid levels, while histopathological findings confirmed structural improvement in hippocampal and cortical regions. Collectively, these results highlight the potential of modified Cs-NPs as a controlled-release, nose-to-brain delivery platform that enhances the therapeutic performance of Ari for the management of schizophrenia.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148697307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-component microneedle drug delivery system of sanfu herbal patch for allergic asthma in rats.","authors":"Ying Lv, Xiaoshuang Li, Yu Wang, Xinxin Qin, Ye Tang, Meng Li, Yufei Feng","doi":"10.1007/s13346-026-02194-7","DOIUrl":"https://doi.org/10.1007/s13346-026-02194-7","url":null,"abstract":"<p><p>A dissolvable microneedle system (SFP-MNs) loaded with seven principal Sanfu Herbal Patch components was developed to assess transdermal delivery feasibility and therapeutic efficacy in a rat model of allergic asthma. SFP-MNs were fabricated using a two-step centrifugation-assisted template molding method and characterized in terms of morphology, mechanical strength, skin penetration capability, and in vitro drug release behavior. An ovalbumin (OVA)-induced allergic asthma model was established in Sprague-Dawley (SD) rats to investigate the in vivo performance of the microneedles. Pulmonary interstitial fluid was continuously sampled by microdialysis following transdermal administration, and drug concentrations were quantified using UPLC-MS/MS. Pharmacodynamic responses were evaluated by measuring histamine (HIS), immunoglobulin E (IgE), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α) levels using ELISA, together with histopathological examination by hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) staining. A pharmacokinetic-pharmacodynamic (PK-PD) model was subsequently established to characterize the relationship between drug exposure and therapeutic response. The prepared SFP-MNs exhibited excellent mechanical properties, efficient skin penetration, and sustained drug release. In vivo, SFP-MNs achieved effective transdermal delivery of the encapsulated components and produced superior therapeutic outcomes compared with an equivalent-dose conventional Sanfu Herbal Patch gel. Specifically, high-dose SFP-MNs markedly alleviated airway inflammation, reduced inflammatory biomarker levels, and attenuated pulmonary histopathological injury in allergic asthmatic rats. These findings demonstrate that SFP-MNs represent a promising transdermal drug delivery platform with the potential to replace conventional Sanfu Herbal Patch for the treatment of allergic asthma while providing sustained drug release and improved therapeutic efficacy.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148697325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dissecting corneal drug permeability under experimental variability and drug cold-start challenges via hybrid machine learning.","authors":"Shuya Xu, Nannan Wang, Yong Tao, Chihua Li, He Song, Defang Ouyang","doi":"10.1007/s13346-026-02195-6","DOIUrl":"https://doi.org/10.1007/s13346-026-02195-6","url":null,"abstract":"<p><p>Corneal drug permeability is a key determinant of topical ocular drug delivery efficiency, yet its quantitative prediction remains challenging due to experimental noise and limited generalizability across drugs. Herein, we systematically integrated ex vivo drug and formulation corneal permeability data and developed a hybrid machine learning framework that jointly incorporates intrinsic and formulation-level information to quantitatively characterize corneal drug permeation under high-noise and drug cold-start conditions. We curated the first comprehensive ex vivo corneal apparent permeability coefficient (P_app) dataset containing 575 formulation records covering 65 active pharmaceutical ingredients (APIs), 85 penetration enhancers, and 4 animal species. We also curated a molecular dataset of 205 drugs representing intrinsic permeation potential, which was used as prior information for formulation-level prediction. Systematic comparison across multiple machine learning algorithms showed that Tabular Prior-data Fitted Network (TabPFN) achieved the best performance, with R² values of 0.54 for molecular permeability and 0.88 for formulation-level prediction. However, performance degraded in scenarios involving unseen drugs. Incorporating molecular permeability as a prior feature reduced cold-start error by 14.6% and achieved an MAE of 0.42 for logP_app, approaching the empirical upper bound of experimental reproducibility (MAE = 0.33) as estimated from cross-source measurements. These results demonstrate that molecular-level information substantially improves model generalization under drug cold-start scenarios. Interpretability analyses indicate that intrinsic molecular permeation establishes a baseline permeability, while formulation components introduce nonlinear, mechanism-specific modulation. Simulation results further demonstrated efficient few-shot generalization across unseen drugs and rapidly improved predictive performance using only limited additional experimental data. Overall, this study establishes an interpretable, hybrid corneal permeability modeling framework for the rational design of ophthalmic formulations. By offering a generalizable paradigm for predicting formulation performance under cross-drug conditions, this framework is poised to benefit the field by enhancing animal welfare and improving drug development efficiency.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148677676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Focused ultrasound-mediated opening of the blood brain barrier for non-invasive drug delivery to the murine cerebellum.","authors":"Stefanyda Maslova, Thomas Sherlock, Andrew T Thede, Zehra E F Demir, Owen Brown, Beyzanur G Ak, Sarah E Duclos, Alec J Batts, Mary Eleanor Hermes, Matthew McCord, Natasha D Sheybani","doi":"10.1007/s13346-026-02196-5","DOIUrl":"10.1007/s13346-026-02196-5","url":null,"abstract":"<p><strong>Background: </strong>The blood brain barrier (BBB) limits effective treatment for cerebellar diseases. Region-specific parameterization and safety data for MRI-guided focused ultrasound (MRgFUS) BBB opening (BBBO) in the cerebellum are scarce. The goal of this study is to establish safety and feasibility of cerebellar BBBO for antibody delivery.</p><p><strong>Methods: </strong>Mice received i.v. AF680 IgG and microbubbles immediately prior to sonication at 0.30 or 0.45 MPa peak negative pressure (1.15 MHz, 10 ms bursts, 2 s burst period, 60 bursts). BBBO was quantified by contrast-enhanced T1-weighted MRI (9.4T) and assessed for recovery at 12 h. Radiologic safety was evaluated by T2-weighted MRI. Acoustic emissions were analyzed via real-time passive cavitation detection, and acoustic simulations estimated the derated pressure caused by skull incidence angle. IgG delivery was quantified by ex vivo IVIS epifluorescence imaging and immunofluorescence analysis. Safety assessments included cardio-respiratory monitoring, body weight, motor function, and neuropathology assessment of endpoint H&E.</p><p><strong>Results: </strong>Both regimens yielded cerebellar BBBO without radiologic evidence of injury. BBB integrity was restored by 12 h. While the higher pressure increased MRI and cavitation signals, IgG delivery was similarly enhanced (> 2-fold vs. sham) by FUS, irrespective of peak negative pressure. Heart rate, respiratory rate, body weight, and motor function were unchanged by FUS, and neuropathologic evaluation revealed no hemorrhage, inflammation, vacuolation, or architectural abnormalities.</p><p><strong>Conclusions: </strong>FUS enables safe, transient BBBO in the cerebellum and significantly enhances antibody delivery without measurable physiologic, functional, radiologic, or histologic injury. These findings establish a foundation for expansion of pharmacologic and theranostic delivery strategies directed to the cerebellum.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148668604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Harnessing synergistic SN38/quercetin nanomicelles via nebulized inhalation for enhanced lung cancer treatment.","authors":"Xudong Fan, Jingming Luo, XiaoQian Tang, Jie Zhang, Ruoying Zhang, Xinjun Cai","doi":"10.1007/s13346-026-02197-4","DOIUrl":"https://doi.org/10.1007/s13346-026-02197-4","url":null,"abstract":"<p><p>Lung cancer remains a leading cause of cancer-related mortality worldwide, while the clinical utility of irinotecan-derived therapies is often constrained by poor drug solubility, suboptimal biodistribution, and systemic toxicity. To overcome these limitations, we developed polymeric nanomicelles co-loading 7-Ethyl-10-hydroxycamptothecin (SN38), the active metabolite of irinotecan, and quercetin, a naturally occurring flavonoid with intrinsic antitumor activity, for nebulized inhalation delivery. The dual-drug nanomicelles (SN38/QU-PPM) were prepared by nanoprecipitation and exhibited a uniform particle size distribution, excellent stability, and pH-responsive drug release under acidic conditions. In vitro studies demonstrated that quercetin co-loading enhanced cellular uptake of the nanomicelles and promoted intracellular accumulation of SN38, resulting in significantly greater cytotoxicity against LLC-Luc lung cancer cells compared with SN38-loaded nanomicelles alone. In an orthotopic lung cancer model, nebulized inhalation of SN38/QU-PPM achieved a 3.33-fold higher pulmonary SN38 concentration than intravenous administration at 24 h. Nebulized SN38/QU-PPM also exhibited superior antitumor efficacy, achieving a tumor inhibition rate of 80.7%, accompanied by increased apoptosis, reduced tumor cell proliferation. Histopathological examination and serum biochemical analyses indicated no apparent treatment-related abnormalities following inhalation administration. Collectively, SN38/QU-PPM delivered via nebulized inhalation represents an effective lung-targeted drug delivery strategy that enhances local drug exposure and potentiates the antitumor efficacy of SN38. This dual-drug nanomicelle platform holds considerable promise for the treatment of lung cancer through nebulized inhalation therapy.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":""},"PeriodicalIF":6.9,"publicationDate":"2026-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148668617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of microneedle array insertion into skin using Raman spectroscopic techniques.","authors":"Rezvan Jamaledin, Panagiota Zarmpi, Adrián M Alambiaga-Caravaca, Vasundhara Tyagi, Qonita Kurnia Anjani, Eneko Larrañeta, Ryan F Donnelly, Natalie A Belsey, Richard H Guy, M Begoña Delgado-Charro","doi":"10.1007/s13346-025-02041-1","DOIUrl":"10.1007/s13346-025-02041-1","url":null,"abstract":"<p><p>Microneedle (MN) arrays bypass the skin's stratum corneum barrier to deliver drugs directly into the viable tissue. The skin disposition of three types of MNs-dissolvable, degradable and hydrogel-forming, fabricated using different polymers-have been evaluated post-treatment with examples of these MN arrays and then examined by confocal Raman spectroscopy and stimulated Raman scattering (SRS) microscopy. The presence of the polymers was assessed from their characteristic Raman signals. SRS image mosaics were acquired to survey and visualise larger areas of the skin surface. After MN insertion, the skin's spectrum was acquired using confocal Raman spectroscopy at the surface, and at nominal depths of 50 µm, 100 µm, and 150 µm. For dissolvable and degradable MNs, Raman signals from the constituent polymers were detectable in the skin. However, the polymer used to form the hydrogel MNs was not detectable under the experimental conditions used. SRS confirmed that the MN arrays penetrated the skin in a reasonably uniform manner. In summary, polymeric MN insertion into the skin has been visualised using confocal Raman spectroscopy and SRS microscopy. Together, these techniques have the potential to shed light on the spatial and temporal skin disposition of the constituent MN polymers used.</p>","PeriodicalId":11357,"journal":{"name":"Drug Delivery and Translational Research","volume":" ","pages":"2976-2989"},"PeriodicalIF":6.9,"publicationDate":"2026-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13346314/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145959149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}