Journal of Medical and Biological Engineering最新文献

{"title":"A New Method for Predicting the Porosity of an Interbody Fusion Cage by the Equivalent Material Method","authors":"","doi":"10.1007/s40846-024-00847-x","DOIUrl":"https://doi.org/10.1007/s40846-024-00847-x","url":null,"abstract":"<h3>Abstract</h3> <span> <h3>Purpose</h3> <p>The interbody fusion cage will cause stress shielding problems due to its material characteristics. This paper aims to find out the change in biomechanical characteristics of porous interbody fusion cages under different conditions and provide a theoretical basis for solving the stress shielding problem.</p> </span> <span> <h3>Methods</h3> <p>The properties of microscopic cells with different porosities are obtained by conducting virtual experiments to demonstrate the material strength of the macroscopic model. Based on the obtained equivalent material properties, the mechanical properties of the porous Ti6Al4V interbody fusion cage in the spine were investigated, and the stress reduction rate under different porosities was analyzed by changing the shape of the fusion cage.</p> </span> <span> <h3>Results</h3> <p>The elastic modulus of the porous fusion cage can be approximately expressed as “<em>E</em> ≈ <em>E</em>₀ (1 − 1.62<em>P </em>− 1.41<em>P</em>² + 4.22<em>P</em>³ − 2.22<em>P</em>⁴).” When <em>P</em> = 90%, the Von Mises stress is reduced by more than 70%, but it approaches the yield strength (85 MPa), and the compressive stress approaches 45 MPa. The two stress reduction rates on the fusion cage with 55% &lt; <em>P</em> &lt; 90% can be approximately expressed in the form of “<em>A</em> + <em>Bx</em> + <em>Cx</em>² + <em>Dx</em>³.”</p> </span> <span> <h3>Conclusion</h3> <p>The relationship between elastic modulus and porosity of equivalent materials is obtained, which provides a theoretical basis for predicting the porosity of fusion cages. Under the osteotomy scheme of this model, two expressions of “<em>P</em>–<em>μ</em>” are obtained, and the applicability of the formulas is verified, which lays a theoretical foundation for further research on the stress problem of the fusion cage.</p> </span>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"42 5","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Integrated Framework for Assessing the Quality of Non-invasive Fetal Electrocardiography Signals","authors":"Yuwei Zhang, Aihua Gu, Zhijun Xiao, Caiyun Ma, Zhongyu Wang, Lina Zhao, Chenxi Yang, Jianqing Li, Chengyu Liu","doi":"10.1007/s40846-024-00852-0","DOIUrl":"https://doi.org/10.1007/s40846-024-00852-0","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Non-invasive fetal electrocardiography (fECG) offers crucial information for assessing early diagnosis of fetal distress and morbidity. However, the non-invasive fECG signals probably contain various non-stationary noises, which may generate a bad influence on signal processing. Signal quality assessment plays a crucial role in accurate feature estimation for obtaining high-quality signals.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>This study develops a comprehensive framework for the assessment of signal quality for non-invasive fECG signals. Firstly, the ECG collection equipment is employed to gather abdominal ECG signal data from eight pregnant women in the hospital. Secondly, signal preprocessing is operated including signal segmentation and data normalization process. Subsequently, a total of thirty-seven signal quality indexes (SQIs) are extracted which consist of the amplitude-based SQI, R-wave-based SQI, statistical-based SQI, fractal dimension SQI, power spectrum distribution-based SQI, and entropy domain-based SQI. Then, in order to reduce the dimensionality of features and improve the experimental performance, information gain is carried out to identify the subset of the optimal features. At last, the classifier combines different feature numbers to classify the quality of the non-invasive fECG signal.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>Ten classifiers are selected to perform a classification task between good-quality and bad-quality abdominal signals. The experimental results show that the combination of twenty-four effective features and random forest achieved the highest classification outcome, which in terms of the ACC, and F1 scores are 0.9508, and 0.9510, respectively.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>The experimental results indicate that our work can reliably assess the signal quality for non-invasive fECG signals and filter out good-quality signals. This proposed algorithm can help to improve the accuracy of fetal signal extraction and fetal heart rate estimation for further analysis, which is beneficial to promoting fetal health monitoring.</p>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"8 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preliminary Study of Dental Caries Detection by Deep Neural Network Applying Domain-Specific Transfer Learning","authors":"Toshiyuki Kawazu, Yohei Takeshita, Mamiko Fujikura, Shunsuke Okada, Miki Hisatomi, Junichi Asaumi","doi":"10.1007/s40846-024-00848-w","DOIUrl":"https://doi.org/10.1007/s40846-024-00848-w","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The purpose of this study is to confirm whether it is possible to acquire a certain degree of diagnostic ability even with a small dataset using domain-specific transfer learning. In this study, we constructed a simulated caries detection model on panoramic tomography using transfer learning.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>A simulated caries model was trained and validated using 1094 trimmed intraoral images. A convolutional neural network (CNN) with three convolution and three max pooling layers was developed. We applied this caries detection model to 50 panoramic images and evaluated its diagnostic performance.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>The diagnostic performance of the CNN model on the intraoral film was as follows: C0 84.6%; C1 90.6%; C2 88.6%. Finally, we tested 50 panoramic images with simulated caries insertion. The diagnostic performance of the CNN model on the panoramic image was as follows: C0 75.0%, C1 80.0%, C2 80.0%, and overall diagnostic accuracy was 78.0%. The diagnostic performance of the caries detection model constructed only with panoramic images was much lower than that of the intraoral film.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>Domain-specific transfer learning methods may be useful for saving datasets and training time (179/250).</p>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"1 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139760043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Effective Integrated Framework for Fetal QRS Complex Detection Based on Abdominal ECG Signal","authors":"","doi":"10.1007/s40846-024-00850-2","DOIUrl":"https://doi.org/10.1007/s40846-024-00850-2","url":null,"abstract":"<h3>Abstract</h3> <span> <h3>Purpose</h3> <p>Non-invasive fetal electrocardiography (fECG) has a promising application prospect in offering crucial information for assessing early diagnosis and intervention of fetal distress and morbidity during pregnancy. Nevertheless, the detection and extraction of fetal ECG signals are still challenging since fetal ECG signals are exceedingly weak, and liability is affected by maternal ECG and other noises.</p> </span> <span> <h3>Methods</h3> <p>In this study, a comprehensive framework is developed for fECG signal extraction and fetal QRS complex location. A negative entropy-based blind source separation (BSS) method combined with a template subtraction (TS) method is exploited to obtain fECG signals from abdominal ECG (aECG) recordings. It effectively combines the arithmetic characteristics of fixed-point iteration and the effectiveness of template filtering, making the algorithm simple and fast to obtain clearer fetal ECG signals. Additionally, the combination of filter transformation and adaptive threshold algorithm is adopted for fetal QRS wave location. The filtering operation makes the fECG signal into single peaks. The design of low threshold and high threshold ensures that R waves can be located and detected more accurately.</p> </span> <span> <h3>Results</h3> <p>The performance results in terms of diagnostic sensitivity (Se), positive predictive value (PPV), accuracy (ACC), and harmonic mean (F1) scores are 96.12%, 96.20%, 92.60%, and 95.94% for the PCDB database, respectively, and 99.78%, 99.10%, 98.88%, and 99.44% for the ADFECGDB database. In addition, the results in terms of Se, PPV, ACC, and F1 scores are 99.46%, 97.89%, 97.37%, and 98.67% for the AECGDB database, respectively.</p> </span> <span> <h3>Conclusion</h3> <p>This study demonstrates that the proposed framework exhibits superior performance, which can improve the accuracy of fetal QRS complex detection.</p> </span>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"35 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Attribute-Enhanced Capsule Network for Pulmonary Nodule Classification","authors":"Yang Xu, Qingshan She, Songkai Sun, Xugang Xi, Shengzhi Du","doi":"10.1007/s40846-024-00846-y","DOIUrl":"https://doi.org/10.1007/s40846-024-00846-y","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Most pulmonary nodule classification methods solely rely on nodule images without considering the corresponding attribute information. Additionally, conventional convolutional structures often fail to capture the relative spatial relationships among different parts of the lung nodule.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>This paper proposes a pulmonary nodule classification method based on attribute privilege and capsule networks. In this approach, eight attribute characteristics of pulmonary nodules are utilized as privileged information during the identification of benign and malignant cases. This additional information empowers the network to distinguish between benign and malignant aspects of pulmonary nodules more accurately. The capsule structure is introduced to help extract and understand the spatial relationships between different parts of the lung nodule images, the Res2net structure is adopted to extract multi-scale information from lung nodules, and an attention mechanism is incorporated into the backbone network to enhance the efficiency of feature extraction. The proposed classification method was thoroughly evaluated through a series of experiments using the LIDC-IDRI dataset.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>The mean identification accuracy of pulmonary nodules reaches 91.6%. This outcome demonstrates that the proposed method is capable of identifying benign and malignant pulmonary nodules with high accuracy.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>The novel lung nodule recognition method based on attribute privilege and capsule network contributes to achieving better feature extraction and addressing the challenge of small training datasets for pulmonary nodules.</p>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"19 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating Ratio Indices Based on Electroencephalogram Brainwaves in Schizophrenia Detection","authors":"","doi":"10.1007/s40846-024-00851-1","DOIUrl":"https://doi.org/10.1007/s40846-024-00851-1","url":null,"abstract":"<h3>Abstract</h3> <span> <h3>Purpose</h3> <p>Extensive research has been conducted by neurocognitive and psychological scientists to diagnose mental and neurological diseases intelligently. Recently, researchers have shown interest in Electroencephalogram (EEG) analysis, a non-invasive method of recording the brain’s electrical activity from the scalp surface. EEG signals contain different frequency bands, each indicating specific brain activities. Although the relative powers of single EEG waves are not all-inclusive indicators to consistently imitate mental involvement, ratio indices should be considered. These indices calculate the ratio of powers (summations) with more than a single frequency band.</p> </span> <span> <h3>Methods</h3> <p>This study quantifies the EEG signals of healthy control and schizophrenic groups using thirty-seven ratio indices based on EEG brainwaves. These indicators are examined for the first time in schizophrenia. The study evaluates which index is more suitable and efficient for solving a classification problem.</p> </span> <span> <h3>Results</h3> <p>The results show the potential of (delta + theta)/alpha in the schizophrenia classification with an average accuracy of 97.92%. Additionally, the study investigates the effectiveness of different EEG electrodes in the problem of schizophrenia diagnosis while utilizing the above indicators. T5, the left posterior temporal region, yields a maximum average accuracy of 92.92%.</p> </span> <span> <h3>Conclusion</h3> <p>In conclusion, the fusion of EEG frequency ratio indices and machine learning algorithms provides a potential avenue for improving the detection and diagnosis of schizophrenia.</p> </span>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"31 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139759757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Carbon Fiber Reinforced Peek on Stabilization of Sagittal Split Ramus Osteotomy Fixation and Stresses on Temporomandibular Joint: 3d Finite Element Analysis Study","authors":"Musa Erdem, Mehmet Zahit BAŞ","doi":"10.1007/s40846-023-00843-7","DOIUrl":"https://doi.org/10.1007/s40846-023-00843-7","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>This study aimed to compare carbon fiber-reinforced polyetheretherketone (CFR-PEEK) plates and screws with conventional titanium plates and screws for mandibular orthognathic surgery models.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>Sagittal split ramus osteotomy (SSRO) was simulated in a 3D finite element model of the mandible. Eight fixation groups with 3 different designs (miniplate, hybrid, and inverted-L) were created using titanium and CFR-PEEK materials. The displacement values in the osteotomy lines, the von Mises stress values on the fixation devices, and the maximum tensile and compressive stress values on the bone in contact with the screws and the temporomandibular joints (TMJ) were compared.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>The displacement in the osteotomy line in the models using the CFR-PEEK polymer was higher than in the titanium models. The stress on the miniplate and screws in the CFR-PEEK models was lower than that in the titanium models. The maximum stress on the miniplates was found close to the fracture line in the distal segment. The stress on the TMJ of the CFR-PEEK models was higher than that of the titanium models.</p><p>When the fixation designs were compared regardless of the material, the lowest displacement value (CFR-PEEK: 0.268 mm; Titanium: 0.253 mm), the highest screw stress (CFR-PEEK: 372.9 MPa; Titanium: 1185.5 MPa), and the lowest bone stress (CFR-PEEK: 57.216 MPa; Titanium:64.022 MPa) were observed in the models using the inverted-L technique for fixation.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>The results suggest that CFR-PEEK plates and screws reduce stress on the fixation systems and the associated bone while increasing stress on the TMJ.</p>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"7 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139508239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Short Implant, Angled Implant, Distal Extension and Grafting Methods for Atrophic Maxillary Posterior Region: a Finite Element Study","authors":"","doi":"10.1007/s40846-023-00844-6","DOIUrl":"https://doi.org/10.1007/s40846-023-00844-6","url":null,"abstract":"<h3>Abstract</h3> <span> <h3>Purpose</h3> <p>The objective of the study was to determine the most ideal of four different implant-prosthesis treatment combinations that can be used for the posterior maxilla by using the finite element method.</p> </span> <span> <h3>Methods</h3> <p>Among the four models representing the posterior region of the atrophic maxilla, in the first model, a standard implant was installed in the place of tooth 4, while a short implant was inserted in the place of tooth 6 due to increased sinus pneumatization. In the second model, standard implants were placed in tooth 4 and 5 and the implant in tooth 5 was installed with 30° distal inclination so as to tangentially cross the sinus region. In the third model, a graft application was designed for the area with increased sinus pneumatization, and standard implants were inserted in the places of tooth 4 and 6. In the fourth model, two standard implants were placed at teeth 4 and 5 and a distal extension was made in between.</p> </span> <span> <h3>Results</h3> <p>The maximum and minimum principal strain values in cortical bone were obtained as 2594 µε and 5478 µε in Model 4, respectively, and in trabecular bone as 4733 µε and 3761 µε in Model 1. Among the implants and abutments, the highest von Mises stress value of 709 MPa occurred in Model 4.</p> </span> <span> <h3>Conclusions</h3> <p>The third model that features a graft was the most successful model and the fourth model that featured distal extension had the highest likelihood of damage.</p> </span>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"35 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2024-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139373886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing Pulmonary Function Parameters Non-invasively by Electrical Bioimpedance Tomography","authors":"F. M. Vargas-Luna, M. I. Delgadillo-Cano, J. P. Riu-Costa, S. Kashina, J. M. Balleza-Ordaz","doi":"10.1007/s40846-023-00842-8","DOIUrl":"https://doi.org/10.1007/s40846-023-00842-8","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Electrical Impedance Tomography (EIT) holds promise as a non-invasive method for measuring lung airflow, particularly in patients diagnosed with Chronic Obstructive Pulmonary Disease (COPD). Nonetheless, there are challenges regarding the clinical relevance of EIT. The main purpose of the present research was to identify the primary frequency components of impedance changes recorded by EIT and correlate them with pulmonary function parameters.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>20 COPD patients were analyzed. Each volunteer was connected to a pneumotachometer and an EIT device. They performed three respiratory exercises, and pulmonary function parameters for each volunteer were acquired. The three impedance signals were convolved to simulate the behavior of the thorax as a black box with a single output signal. The convolved impedance signal was analyzed using FFT spectra. Subsequently, it was divided into seven frequency ranges, estimating the area under the curve and quartiles at 25%, 50%, and 75%. Each segment of the FFT spectrum was correlated with each pulmonary function test parameter.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>A significant correlation of over 60% between pulmonary function test parameters and the determinations from the FFT spectrum within seven distinct frequency ranges was observed. However, the determination coefficient (<i>R</i>²) ranged from approximately 10–66% due to data points that did not fit well, particularly in patients with severe pulmonary dysfunction.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>To address the dispersion of data and enhance the correlation between determinations, it is imperative to adjust impedance determinations using anthropometric parameters or employ a mathematical equation that facilitates the characterization of limitations in lung airflow.</p>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"65 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139055541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Influence of Surface Modification on the Shortwave Infrared Emission of Rare-Earth-Doped Nanoparticles","authors":"Mohd Yaqub Khan, Jen-Kun Chen, Vivek Jain, Lokesh Agrawal, Cheng-An J. Lin, Min-Hua Chen","doi":"10.1007/s40846-023-00841-9","DOIUrl":"https://doi.org/10.1007/s40846-023-00841-9","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Deep tissue imaging can be achieved using shortwave infrared (SWIR) light, ranging from 900 to 2500 nm in wavelength. SWIR light has several advantages, such as low scattering, reduced photobleaching and autofluorescence, and high sensitivity for biological samples. One of the most efficient materials for SWIR emission is rare-earth-doped nanoparticles (RENP), but they are hydrophobic and incompatible with biological systems. Therefore, we use common surface modifiers, such as polyethylene glycol (PEG) and Tween 20 (Tw), to improve the biocompatibility and dispersibility of RENP in aqueous media. This study aims to evaluate the effects of PEG and Tw as surface modifiers on the stability and SWIR emission intensity of RENP.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>Using the thermal decomposition method, we prepared RENP (NaYF₄: Yb, Er) and modified their surface with PEG and Tw. RENP were modified with PEG and Tw using simple phase inversion and sonication-assisted methods, respectively. We characterized the RENP-PEG and RENP-Tw by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FTIR) spectroscopy, zeta potential, and thermogravimetric analysis (TGA). We also measured the SWIR emission and spectra of the RENP-PEG and RENP-Tw using a Ninox 640 VIS-SWIR InGaAs camera with a 980 nm NIR laser excitation. To assess the biocompatibility of RENP-Tw, we performed an MTT assay with L929 cells.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>The XRD and FTIR analyses confirmed the successful surface modification of RENP and the formation of the hexagonal phase β-NaYF₄. The FTIR spectra showed the characteristic peaks of the functional groups associated with PEG and Tw. The surface modification also changed the zeta potential values of RENP, indicating different surface charges. The stability studies revealed that RENP-Tw remained well-dispersed in aqueous media after 24 h, while RENP-PEG aggregated over time. The RENP-Tw showed bright SWIR emission and a prominent peak at 1385 nm. The biocompatibility assay revealed that RENP-Tw did not cause significant cytotoxicity even at high concentrations (400 μg/mL) for 24 h.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>Based on our findings, we propose that Tw is a suitable modifier for rare-earth-doped nanoparticles' performance as a SWIR agent, as it improves their stability properties in aqueous media, biocompatibility, and luminescence emissions.</p>","PeriodicalId":50133,"journal":{"name":"Journal of Medical and Biological Engineering","volume":"77 1","pages":""},"PeriodicalIF":2.0,"publicationDate":"2023-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139051330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}