polylactic acid

聚乳酸
  • 文章类型: Journal Article
    与其他蒽环类药物相比,吡柔比星具有较高的治疗效果和降低的毒性,因此在临床研究中引起了广泛的关注。然而,~30%接受PIRA治疗的患者仍经历复发和转移。临床进展揭示了存在于肿瘤中的癌症干细胞(CSC)构成了这种限制的主要因素,并且随后是治疗失败的原因。因此,与大块肿瘤一起根除CSC是获得最大治疗效果的关键任务。然而,目前正在检查的大多数CSC抑制剂缺乏特异性,与其他主要治疗方法表现出不同步的生物利用度,并在其治疗应用中表现出明显的毒性,这主要归因于它们的肿瘤靶向能力不足。因此,我们开发了一种可生物降解的聚乳酸基共混嵌段共聚物NP,用于同时递送CSC抑制剂盐霉素(SAL)和化疗药物吡柔比星(PIRA),旨在提高治疗疗效和预防癌症复发.制备的NP显示<100nm的尺寸和优异的负载,这两种药物持续释放。此外,PIRA:SAL共负载的NP表现出协同增强的针对癌细胞以及CSC的细胞毒性。最重要的是,NPs介导的药物共同递送显示肿瘤完全根除,在整个监测期间没有任何复发。此外,NPs治疗未显示重要器官的任何组织病理学改变,证实其无毒性质。总之,本研究得出结论,开发的PIRA:SALNP对肿瘤消退以及预防癌症复发具有优异的疗效,因此可用作癌症治疗的潜在联合疗法。
    Pirarubicin attracted considerable attention in clinical studies because of its high therapeutic efficacy and reduced toxicity in comparison with other anthracyclines. Nevertheless, ~ 30% patients undergoing PIRA treatment still experience relapse and metastasis. Clinical advancements unveiled that cancer stem cells (CSCs) residing in the tumor constitutes a major factor for such limitations and subsequently are the reason for treatment failure. Consequently, eradicating CSCs alongside bulk tumor is a crucial undertaking to attain utmost therapeutic efficacy of the treatment. Nevertheless, majority of the CSCs inhibitors currently under examination lack specificity, show unsynchronized bioavailability with other primary treatments and exhibit notable toxicity in their therapeutic applications, which is primarily attributable to their inadequate tumor-targeting capabilities. Therefore, we have developed a biodegradable polylactic acid based blend block copolymeric NPs for concomitant delivery of CSCs inhibitor Salinomycin (SAL) & chemotherapeutic drug Pirarubicin (PIRA) with an aim to improve the efficacy of treatment and prevent cancer relapse. Prepared NPs showed < 100 nm size and excellent loading with sustained release for both the drugs. Also, PIRA:SAL co-loaded NPs exhibits synergistically enhanced cytotoxicity against cancer cell as well as CSCs. Most importantly, NPs mediated co-delivery of the drugs showed complete tumor eradication, without any reoccurrence throughout the surveillance period. Additionally, NPs treatment didn\'t show any histopathological alteration in vital organs confirming their non-toxic nature. Altogether, present study concludes that the developed PIRA:SAL NPs have excellent efficacy for tumor regression as well as prevention of cancer relapse, hence can be used as a potential combination therapy for cancer treatment.
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  • 文章类型: Journal Article
    骨损伤是一个紧迫的临床问题,和可植入的生物支架为替换和再生受损组织提供了合适的手段。本文提出了一种采用材料挤出增材制造技术和物理发泡法制备聚乳酸/甲壳素纳米晶体(CHNC)微孔复合支架的原位发泡印刷方法,具有孔径范围为9±5μm。该方法为制备具有良好生物相容性的基于聚乳酸的支架提供了新的策略。材料表征和力学性能测试表明,原位发泡印刷PLA支架具有优异的泡沫适印性,通过改变CHNC浓度和打印速度,可以调节支架的膨胀比和压缩性能,压缩模量在39.2MPa和54.3MPa之间。此外,在等效发泡倍数(1.5-2.6倍)下,与先前报道的基于PLA的泡沫支架相比,压缩模量增加了近100%。重要的是,与直接打印的PLA支架相比,通过原位发泡生产的PLA/CHNC支架表现出优异的生物相容性。这种PLA/CHNC复合支架为解决和修复骨缺损提供了一种有前途的方法。
    Bone injury represents an urgent clinical problem, and implantable bioscaffolds offer suitable means for replacing and regenerating damaged tissues. This paper proposes an in-situ foaming printing method employing material extrusion additive manufacturing technology and physical foaming to prepared poly(lactic acid)/chitin nanocrystals (CHNCs) microporous composite scaffolds, featuring pore sizes ranging from 9 ± 5 μm. This method offers a novel strategy for the preparation of poly(lactic acid)-based scaffolds with good biocompatibility. Material characterization and mechanical property testing demonstrated that the in-situ foaming printed PLA scaffolds exhibited excellent foam printability, and the expansion ratio and compression properties of the scaffolds could be adjusted by modifying the CHNCs concentration and the printing speed, achieving a compression modulus between 39.2 MPa and 54.3 MPa. Furthermore, at equivalent foaming multiplicity (1.5-2.6 times), the compression modulus increased by nearly 100 % compared to previously reported PLA-based foam scaffolds. Importantly, the PLA/CHNCs scaffolds produced via in-situ foaming exhibited superior biocompatibility compared to directly printed PLA scaffolds. This PLA/CHNCs composite scaffold provides a promising approach to addressing and repairing bone defects.
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  • 文章类型: Journal Article
    聚乳酸(PLA)木塑复合材料由于其可生物降解性,与传统的石油基塑料相比具有显着优势。然而,解放军有几个缺点,包括高脆性,低耐热性,缓慢结晶,与生物质材料的相容性差,这限制了其潜在的应用。在本文中,我们研究了羧基封端的超支化聚酯(CHBP)对机械,结晶,聚乳酸/秸秆粉(SF)共混物通过挤出注塑成型的热性能。此外,我们加入传统增塑剂聚乙二醇(PEG)与CHBP协同增强PLA/SF复合材料的韧性。我们的结果表明,适当添加CHBP可以有效地改善PLA与秸秆粉之间的界面结合。CHBP的掺入也提高了拉伸强度,弯曲强度,冲击强度,断裂伸长率,热稳定性,和复合材料的结晶速率。此外,与单独使用PEG相比,CHBP和PEG的加入显著提高了复合材料的冲击强度。该方法还提高了材料的耐热性,减少了增塑剂的迁移。我们的研究证明了使用超支化聚合物和增塑剂来增强韧性的可行性,热稳定性,聚乳酸木塑复合材料的结晶性能,为提高这些复合材料的性能提供了新的途径。
    Polylactic acid (PLA) wood-plastic composites have a significant advantage over traditional petroleum-based plastics due to their biodegradability. However, PLA has several shortcomings, including high brittleness, low heat resistance, slow crystallization, and poor compatibility with biomass materials, which have limited its potential applications. In this paper, we investigated the effects of carboxy-terminated hyperbranched polyester (CHBP) on the mechanical, crystalline, and thermal properties of PLA/straw flour (SF) blends through extrusion injection molding. Additionally, we added the traditional plasticizer polyethylene glycol (PEG) to synergize with CHBP to enhance the toughness of PLA/SF composites. Our results showed that the appropriate addition of CHBP effectively improved the interfacial bonding between PLA and straw flour. The incorporation of CHBP also improved the tensile strength, bending strength, impact strength, elongation at break, thermal stability, and crystallization rate of the composites. Furthermore, the addition of both CHBP and PEG significantly improved the impact strength of the composites compared to using PEG alone. This method also improved the heat resistance of the material and reduced the migration of plasticizers. Our study demonstrates the feasibility of using hyperbranched polymers and plasticizers to enhance the toughness, thermal stability, and crystalline properties of PLA wood-plastic composites, providing a new approach to improving the properties of these composites.
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  • 文章类型: Journal Article
    这项研究提出了一个全面的分析,包括熔融共混,表征,生命周期评估(LCA)以及一系列聚乳酸(PLA)/淀粉生物复合材料的3D打印,淀粉含量从0到50重量%变化。为了增强淀粉颗粒和PLA基质之间的相容性,我们利用无溶剂的方法将N-十八烷基异氰酸酯(ODI)分子接枝到淀粉颗粒的表面上,产生ODI-g-淀粉,这产生了几个改进的性能。值得注意的是,韧性和断裂伸长率提高了约170%和300%,分别。此外,结晶度从普通PLA的11.6%增加到30.1%,表明ODI-g-淀粉颗粒的均匀分散充当PLA链结晶的成核位点。此外,随着ODI-g-淀粉颗粒的引入,粘度显着降低,表明它们的塑化效果,从而提高生物复合材料的加工性能和制造的容易性。至关重要的是,我们的LCA分析显示这些生物复合材料的碳足迹显着减少,高达18%和63%,与普通聚乳酸和精选的化石基塑料相比,分别,在掺入ODI-g-淀粉后。总之,我们的研究介绍了新开发的PLA/淀粉生物复合材料作为一种可持续和生态友好的替代商用普通PLA和特定的化石基塑料。
    This study presents a comprehensive analysis encompassing melt blending, characterization, life cycle assessment (LCA), and 3D printing of a range of polylactic acid (PLA)/starch biocomposites, with starch content varying from 0 to 50 wt%. To enhance compatibility between the starch particles and the PLA matrix, we utilized a solvent-free method to graft N-octadecyl isocyanate (ODI) molecules onto the surface of the starch particles, resulting in ODI-g-starch, which yielded several improved properties. Notably, toughness and elongation at break improved by approximately 170 % and 300 %, respectively. Moreover, the crystallinity increased from 11.6 % in plain PLA to 30.1 %, suggesting that the uniform dispersion of ODI-g-starch particles acted as nucleating sites for the crystallization of PLA chains. Additionally, viscosity decreased significantly with the introduction of ODI-g-starch particles, indicating their plasticizing effect, thereby enhancing the processability and ease of fabrication of the biocomposite. Crucially, our LCA analysis revealed a significant reduction in the carbon footprint of these biocomposites, up to 18 % and 63 %, compared to plain PLA and selected fossil-based plastics, respectively, upon the incorporation of ODI-g-starch. In summary, our research introduces the newly developed PLA/starch biocomposites as a sustainable and eco-friendly alternative to commercially available plain PLA and specific fossil-based plastics.
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  • 文章类型: Journal Article
    正确的废物分类对于生物降解塑料(BDP)回收至关重要,其全球产量正在动态增长。BDP可以使用近红外(NIR)分选,但是关于表面污染对其近红外光谱的影响的研究很少,这影响了它们的可分选性。由于BDP经常受到食物垃圾的严重污染,了解表面污染的影响是必要的。本文报道了一项关于使用食物垃圾人工诱导的表面污染和包装垃圾污染的影响的研究,生物废弃物,和BDP光谱上的残余废物。在人工污染的样本中,吸收带(AD)由于水分(1352-1424nm)和脂肪酸(1223nm)的存在而改变。在现实世界的污染样本中,生物废弃物样品受污染影响最大,其次是残留废物,均在1352-1424nm(水分)处具有改变的AD。包装废物污染的样品光谱紧跟清洁和洗涤样品的光谱,随着广告强度的变化。因此,在分类中可以遵循两种方法:(I)可以省略受影响的波长范围,或(ii)污染样品可用于优化NIR数据库。因此,表面污染影响光谱,并且知道包含这种效应的波长范围可用于优化NIR数据库并改善BDP分选。
    Proper waste sorting is crucial for biodegradable plastics (BDPs) recycling, whose global production is increasing dynamically. BDPs can be sorted using near-infrared (NIR) sorting, but little research is available about the effect of surface contamination on their NIR spectrum, which affects their sortability. As BDPs are often heavily contaminated with food waste, understanding the effect of surface contamination is necessary. This paper reports on a study on the influence of artificially induced surface contamination using food waste and contamination from packaging waste, biowaste, and residual waste on the BDP spectra. In artificially contaminated samples, the absorption bands (ADs) changed due to the presence of moisture (1352-1424 nm) and fatty acids (1223 nm). In real-world contaminated samples, biowaste samples were most affected by contamination followed by residual waste, both having altered ADs at 1352-1424 nm (moisture). The packaging waste-contaminated sample spectra closely followed those of clean and washed samples, with a change in the intensity of ADs. Accordingly, two approaches could be followed in sorting: (i) affected wavelength ranges could be omitted, or (ii) contaminated samples could be used for optimizing the NIR database. Thus, surface contamination affected the spectra, and knowing the wavelength ranges containing this effect could be used to optimize the NIR database and improve BDP sorting.
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  • 文章类型: Journal Article
    结直肠癌(CRC)是最常见和最具挑战性的恶性肿瘤之一,需要一些有效和更安全的化疗药物来治疗。在这项研究中,抗癌剂表柔比星(Epi)被装载在聚合物聚乙二醇-聚乳酸-纳米颗粒(mPEG-PLA-NP)包被的海洋抗癌无毒多糖岩藻依聚糖(FC),以实现针对CRC的协同活性。NPs的表征显示它们是球形的,单分散,稳定,具有负的zeta电位,并表现出良好的生物相容性和控制释放。发现NPs对HCT116细胞系的体外抗癌活性是有希望的,并与注射C26鼠癌细胞的BALB/C小鼠的体内研究得到了很好的证实。MTT测定结果表明游离Epi的IC50值为3.72µM,未涂覆和涂覆的Epi纳米制剂的含量为33.67和10.19µM,分别。较高的肿瘤消退,当这种新型NP制剂用于治疗荷瘤小鼠时,观察到更好的存活率和降低的场外心脏毒性。游离FC和Epi处理的小鼠显示肿瘤大小的37.73%和61.49%消退,而有79.76%和90.34%肿瘤消退的小鼠用无涂层EpiNP和有涂层EpiNP治疗,分别。因此,mPEG-PLA-FC-Epi-NP具有作为抗CRC的有效化疗制剂的潜力,因为它表现出更好的疗效和更低的毒性。
    Colorectal cancer (CRC) is one of the most common and challenging malignancy that needs some effective and safer chemotherapeutic agents for the treatment. In this study, anticancer agent epirubicin (Epi) was loaded in polymeric polyethylene glycol-polylactic acid-nanoparticles (mPEG-PLA-NPs) coated with a marine anti-cancer non-toxic polysaccharide fucoidan (FC), to achieve a synergistic activity against CRC. The characterization of the NPs revealed that they were spherical, monodispersed, stable, with a negative zeta potential, and exhibited good biocompatibility and controlled release. In vitro anti-cancer activity of the NPs on HCT116 cell line was found to be promising, and corroborated well with in vivo studies involving BALB/C mice injected with C26 murine cancer cells. The outcome of MTT assay demonstrated that IC50 value of free Epi was 3.72 µM, and that of non-coated and coated Epi nano-formulations was 33.67 and 10.19 µM, respectively. Higher tumor regression, better survival and reduced off-side cardiotoxicity were observed when this novel NPs formulation was used to treat tumor-bearing mice. Free FC and Epi treated mice showed 37.73 % and 61.49 % regression in tumor size, whereas there was 79.76 % and 90.34 % tumor regression in mice treated with non-coated Epi NPs and coated Epi NPs, respectively. Therefore, mPEG-PLA-FC-Epi-NPs hold a potential to be used as an effective chemotherapeutic formulation against CRC, since it exhibited better efficacy and lower toxicity.
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  • 文章类型: Journal Article
    微塑料和重金属污染经常在海洋环境中同时发生,引起人们对它们对海洋鱼类的潜在有害影响的担忧。这项研究对聚乳酸微塑料(PLA-MPs)和铬(Cr)对海洋medaka幼虫的单独和联合应力效应进行了综合评估。在暴露于PLA-MPs(100μg/L)和Cr(50μg/L)14天后,无论是单独还是组合,观察到心率和体长显着增加。值得注意的是,PLA-MPs和Cr的联合暴露导致了明显的组织病理学改变,包括脱落,萎缩,和肠组织的裂解。此外,个体和联合暴露都会引起鱼幼虫的氧化应激,导致各种酶活性指数的变化。个体暴露于PLA-MPs或Cr导致幼虫的焦虑行为,而联合暴露不仅会导致焦虑行为,还会改变游泳模式。这些发现表明,联合暴露于PLA-MPs和Cr会加剧对海洋medaka幼虫的毒性作用。
    Microplastics and heavy metal pollution frequently co-occur in the marine environment, raising concerns about their potentially harmful impacts on marine fish. This study undertook a comprehensive evaluation of the individual and combined stress effects of polylactide microplastics (PLA-MPs) and chromium (Cr) on marine medaka larvae. Following a 14-day exposure to PLA-MPs (100 μg/L) and Cr (50 μg/L), both individually and in combination, significant increases in heart rate and body length were observed. Notably, the combined exposure to PLA-MPs and Cr caused marked histopathological alterations, including shedding, atrophy, and lysis of the intestinal tissues. Furthermore, both individual and combined exposure induced oxidative stress in fish larvae, leading to changes in various enzyme activity indices. Individual exposure to either PLA-MPs or Cr led to anxious behavior in the larvae, whereas combined exposure not only caused anxious behavior but also altered swimming patterns. These findings suggest that combined exposure to PLA-MPs and Cr can exacerbate the toxic effects on marine medaka larvae.
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  • 文章类型: Journal Article
    一种新颖的稀土络合物,Eu(IAA)2(phen)2(EuIP),采用基于溶液的合成方法合成。然后,将EuIP和聚乳酸(PLA)在190°C下熔融共混以获得多功能PLA/EuIP复合材料。EuIP的掺入为PLA/EuIP复合材料提供了良好的光转换能力。在紫外线照射下,PLA/EuIP复合材料将吸收的紫外光转化为红光。此外,PLA/1.0EuIP复合材料在可见光区域表现出88%的优异透光率,并在紫外光下表现出强烈的红色发射。紫外线照射96小时后,纯PLA的分子量和力学性能急剧下降。有趣的是,UV辐照96h后,PLA/EuIP复合材料的分子量和力学性能没有下降。原因是EuIP可以吸收紫外光并利用吸收的能量发出红色荧光。此外,PLA/EuIP复合材料对大肠杆菌和金黄色葡萄球菌具有良好的抗菌活性。此外,体外细胞实验表明,PLA/EuIP复合材料适用于小鼠乳腺癌(4T1)细胞的生长。此外,酶降解试验也证明了PLA/EuIP复合材料具有良好的生物降解性。这项工作为制备具有光转换能力的PLA/EuIP复合材料提供了一种巧妙的设计策略,抗紫外线,和抗菌性能。
    A novel rare earth complex, Eu(IAA)2(phen)2 (EuIP), was synthesized by solution-based synthesis method. Then, EuIP and polylactic acid (PLA) were melt-blended at 190 °C to obtain a multifunctional PLA/EuIP composite. The incorporation of EuIP provided PLA/EuIP composites with good light conversion ability. Under UV irradiation, PLA/EuIP composites converted the absorbed UV light into red light. Moreover, the PLA/1.0EuIP composite exhibited excellent light transmittance of 88 % in the visible region and showed strong red emission under UV light. After UV irradiation for 96 h, the molecular weights and mechanical properties of neat PLA decreased dramatically. Interestingly, the molecular weights and mechanical properties of PLA/EuIP composites did not deteriorate after 96 h of UV irradiation. The reason was that EuIP could absorb UV light and utilize the absorbed energy to emit red fluorescence. Furthermore, PLA/EuIP composites showed good antibacterial activities against E. coli and S. aureus. In addition, in vitro cell experiments showed that PLA/EuIP composites was suitable for the growth of murine breast cancer (4 T1) cells. Besides, enzymatic degradation testing also proved that PLA/EuIP composites had good biodegradability. This work provides an ingenious design strategy for the preparation of PLA/EuIP composites possessing light conversion ability, UV resistance, and antibacterial properties.
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  • 文章类型: Journal Article
    越来越多的证据强调了微塑料(MPs)对作物的负面影响,生物基塑料提供了传统塑料的替代品。然而,关于生物基MP对作物生理学的影响和机制的知识有限。在这项研究中,将生物基聚乳酸(PLA)和石油基MP[聚酰胺(PA)和聚丙烯(PP)]添加到种植水稻(OryzasativaL.)幼苗的水培培养物中,以评估其毒性。与PA和PPMPs相比,解放军国会议员在接触28天后经历了更大的衰老,它们的表面装载了更多具有潜在塑料降解能力的杆状微生物,比如变形杆菌和类杆菌,与水稻幼苗竞争碳源和氮源进行自我繁殖,从而改变水稻幼苗生长过程中的碳固定和氮循环过程。PLA处理中氨基酸和脂质代谢的下调抑制了水稻幼苗叶片中叶绿素的正常合成。因此,在PLAMP处理中观察到水稻幼苗根和芽的生物量和高度降低。这项研究提供了证据,表明生物基MP可能比石油基MP对作物生长产生更严重的影响。
    Increasing evidence highlights the negative effects of microplastics (MPs) on crops and bio-based plastics offer an alternative to conventional plastics. However, there is limited knowledge on the impacts and mechanisms of bio-based MPs on crop physiology. In this study, bio-based polylactic acid (PLA) and petroleum-based MPs [polyamide (PA) and polypropylene (PP)] were added to hydroponic cultures planted with rice (Oryza sativa L.) seedlings to assess their toxicity. Compared to PA and PP MPs, PLA MPs experienced greater aging after 28 days of exposure, and their surfaces were loaded with more rod-shaped microorganisms with potential plastic degradation ability, such as Proteobacteria and Bacteroidota, which competed with rice seedlings for carbon and nitrogen sources for self-multiplication, thus altering the carbon fixation and nitrogen cycling processes during rice seedling growth. Down-regulation of amino acid and lipid metabolisms in the PLA treatment inhibited the normal synthesis of chlorophyll in rice seedling leaves. Consequently, decreases in the biomass and height of rice seedling roots and shoots were observed in the PLA MP treatment. This study provides evidence that bio-based MPs may have a more severe impact on crop growth than petroleum-based MPs.
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  • 文章类型: Journal Article
    聚乳酸(PLA)秸秆具有环保潜力;然而,用于增强机械强度的残留二异氰酸酯会产生致癌的伯芳胺(PAAs),构成健康风险。在这里,我们提出了一个快速的,在18个品牌的食品级PLA吸管中检测PAA并评估其迁移到各种食品模拟物中的综合策略。进行表面增强拉曼光谱以快速筛选秸秆中的PAAs。随后,定性测定将PAAs迁移到各种食品模拟物中(4%乙酸,10%乙醇,50%乙醇)在70°C下使用液相色谱-质谱法进行2小时。三种PAA,包括4,4'-亚甲基二苯胺,2,4'-亚甲基二苯胺,在所有秸秆中均检测到2,4-二氨基甲苯。具体来说,50%乙醇中的2,4-二氨基甲苯超过2μg/kg的特定迁移极限,引发安全担忧。值得注意的是,在短短2小时内,PAAs向10%和50%乙醇的迁移超过了4%乙酸。此外,PLA秸秆在迁移前后发生了不同程度的形状变化。与没有聚(丁二酸丁二醇酯)的秸秆相比,具有抗变形性,表明增强的耐热性,而聚(己二酸丁二醇酯-共对苯二甲酸酯)改善了耐水解性。重要的是,溶胀研究表明,溶胀作用不是导致乙醇食品模拟物中PAAs迁移增加的主要因素,因为不同食物模拟物的肿胀程度没有显着差异。FT-IR和DSC分析显示,50%乙醇中较高的PAA含量是由于高浓度的极性乙醇破坏了氢键和将PLA分子保持在一起的范德华力。总的来说,减少聚乳酸吸管和酒精食品之间的接触对于避免PAA带来的潜在安全风险至关重要。
    Polylactic acid (PLA) straws hold eco-friendly potential; however, residual diisocyanates used to enhance the mechanical strength can generate carcinogenic primary aromatic amines (PAAs), posing health risks. Herein, we present a rapid, comprehensive strategy to detecting PAAs in 18 brands of food-grade PLA straws and assessing their migration into diverse food simulants. Surface-enhanced Raman spectroscopy was conducted to rapidly screen straws for PAAs. Subsequently, qualitative determination of migrating PAAs into various food simulants (4 % acetic acid, 10 % ethanol, 50 % ethanol) occurred at 70 °C for 2 h using liquid chromatography-mass spectrometry. Three PAAs including 4,4\'-methylenedianiline, 2,4\'-methylenedianiline, and 2,4-diaminotoluene were detected in all straws. Specifically, 2,4-diaminotoluene in 50 % ethanol exceeded specific migration limit of 2 μg/kg, raising safety concerns. Notably, PAAs migration to 10 % and 50 % ethanol surpassed that to 4 % acetic acid within a short 2-hour period. Moreover, PLA straws underwent varying degrees of shape changes before and after migration. Straws with poly(butylene succinate) resisted deformation compared to those without, indicating enhanced heat resistance, while poly(butyleneadipate-co-terephthalate) improved hydrolysis resistance. Importantly, swelling study unveiled swelling effect wasn\'t the primary factor contributing to the increased PAAs migration in ethanol food simulant, as there was no significant disparity in swelling degrees across different food simulants. FT-IR and DSC analysis revealed higher PAAs content in 50 % ethanol were due to highly concentrated polar ethanol disrupting hydrogen bonds and van der Waal forces holding PLA molecules together. Overall, minimizing contact between PLA straws and alcoholic foods is crucial to avoid potential safety risks posed by PAAs.
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