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材料化学英文Materials Chemistry。
Materials chemistry is a branch of chemistry that focuses on the study of the properties and applications of materials. It involves the synthesis, characterization, and manipulation of materials to create new and improved products. The field of materials chemistry is interdisciplinary, drawing on principles from chemistry, physics, and engineering to understand and control the behavior of materials.One of the key areas of materials chemistry is the development of new materials with specific properties for various applications. This involves the design and synthesis of materials with tailored properties, such as strength, conductivity, or optical properties. For example, materials chemists may work to develop new materials for use in electronics, energy storage, or biomedical applications.In addition to creating new materials, materials chemistry also focuses on understanding the structure-property relationships of existing materials. By studying the atomic and molecular structure of materials, researchers can gain insight into their properties and behavior. This knowledge can then be used to develop strategies for improving the performance of materials or creating new materials with enhanced properties.Materials chemistry also plays a crucial role in the development of sustainable and environmentally friendly materials. With the growing concern over the environmental impact of traditional materials and manufacturing processes, materials chemists are working to develop new materials and processes that are more sustainable. This may involve the use of renewable resources, the development of biodegradable materials, or the design of materials with reduced energy and resource requirements.Another important aspect of materials chemistry is the study of materials under extreme conditions, such as high temperatures, pressures, or radiation. Understandinghow materials behave under these conditions is essential for applications in fields such as aerospace, nuclear energy, and high-performance materials.In conclusion, materials chemistry is a diverse and dynamic field that plays a critical role in the development of new materials and the improvement of existing materials. By understanding the structure-property relationships of materials and developing new materials with tailored properties, materials chemists are driving innovation and addressing important challenges in areas such as energy, healthcare, and the environment. As the field continues to evolve, materials chemistry will undoubtedly play an increasingly important role in shaping the future of technology and society.。
薯蓣皂苷元衍生物的合成及生物活性研究摘要:薯蓣皂苷元具有多种药理活性，根据薯蓣皂苷元表现出不同的生物活性，以薯蓣皂苷元为起始原料采取酯化、还原等化学反应进行适当结构修饰，得到多种类型的薯蓣皂苷元衍生物，可减少薯蓣皂苷元的毒副作用，增加其抗血栓、抗炎及松弛支气管平滑肌的药理活性，使薯蓣皂苷元在临床的应用更加广泛，为薯蓣皂苷元更进一步的研究及利用提供一些新的思路。
关键词:薯蓣皂苷元衍生物合成生物活性抗血栓抗炎薯蓣皂苷元（diosgenin，简称Dio）主要是从薯蓣科植物穿龙薯蓣[1]Dioscorea nipponica Makino中得到的甾体皂苷元，俗称皂素。
它是由C螺甾27烷皂苷组成的一类具有广泛生物活性的中药，在临床中常用作一些药物的半合成原料，在制药工业中常用作合成甾体激素类药物和甾体避孕药[2]。
薯蓣皂苷元主要通过促进细胞凋亡、降低氧化应激、抑制促炎因子等来发挥抗肿瘤、抗炎、保护心血管、松弛平滑肌等作用[3]。
然而，薯蓣皂苷元的脂溶性强，口服生物利用度较低，几乎很难吸收入血，很大程度上影响了药理作用的发挥。
在C-3位置引入酯或醚键可显著增大薯蓣皂苷元的极性及溶解度，同时保持其原有的优势[4,5]。
因此有必要对其进行适当的结构改造，使薯蓣皂苷元的溶解性及溶出度在一定程度上增加，从而增强其生物活性。
本文就近年来以薯蓣皂苷元为基础原料进行适当结构改造，得到一系列薯蓣皂苷元衍生物并对其相应的生物活性进行了归纳总结，以期提供更有意义的参考来进一步研究及利用薯蓣皂苷元。
1 薯蓣皂苷元的结构修饰及其抗血栓形成活性乙酰水杨酸即阿司匹林，在临床上常作为解热镇痛药使用，研究表明其小剂量使用时具有防止血栓形成作用，可作为预防血管疾病的药物在临床上使用，但其会造成出血风险、胃黏膜损害和耐药性等不良反应[6,7]。
据报道，薯蓣皂苷元具有保护胃肠道黏膜的功能，但其不溶于水导致吸收差影响了其应有的疗效，因此要采取适当增溶措施，以增强薯蓣皂苷元抗血栓形成活性，并减轻胃肠道不良反应。
三联吡啶的合成及其金属配合物研究进展1 前言配位化学早期是在无机化学基础上发展起来的一门边沿学科，如今，配位化学在有机化学与无机化学的交叉领域受到化学家门广泛的关注。
有机-金属配合物在气体分离、选择性催化、药物运输和生物成像等方面都有潜在的应用前景，因此日益成为化学研究的热点领域[1-4]。
多联吡啶金属配合物在现代配位化学中占据着不可或缺的位置，常见的多联吡啶配体包括2,2'-二联吡啶（bpy）和2,2':6',2''-三联吡啶（tpy）（Fig. 1），Hosseini就把bpy 称为“最广泛应用的配体”[5]，与其类似的具有三配位点的tpy的合成及其金属配合物的研究同样是化学家们研究的热点[6-8]。
Fig 1.三联吡啶的三个吡啶环形成一个大的共轭体系，具有很强的σ给电子能力，配合物中存在金属到配体的d一π*反馈成键作用，因而能与大多数金属离子均形成稳定结构的配合物。
然而，三联吡啶金属络合物的特殊的氧化还原和光物理性质受其取代基电子效应的影响。
因此，通过引入不同的取代基，三联吡啶金属络合物可用于荧光发光装置以及光电开关等光化学领域[9-10]。
在临床医学和生物化学领域中，不管是有色金属的测定还是作为DNA的螯合试剂，三联吡啶衍生物都具有非常广泛的应用前景[11-12]。
2 三联吡啶的合成研究进展正因为三联吡啶在许多领域都具有潜在的应用价值，所以对其合成方法的研究十分重要。
三联吡啶的合成由来已久，早在1932年，Morgan就首次用吡啶在FeCl3存在下反应合成分离出了三联吡啶，并发现了三联吡啶与Fe(Ⅱ)的配合物[13]。
目前，合成三联吡啶的方法主要有成环法和交叉偶联法两种。
2.1 成环法成环法中最常用的反应是Kröhnke缩合反应（Scheme 1）[14]，首先2-乙酰基吡啶溴化得到化合物2，2与吡啶反应生成吡啶溴盐3，3与α,β-不饱和酮4进行Michael加成反应得到二酮5，在醋酸铵存在下进而关环得到三联吡啶。
应用双金属氰化物催化剂和不同起始剂合成聚醚酯多元醇韩宏伟;朱丙清;顾尧【摘要】环氧丙烷和二氧化碳在双金属氰化物(DMC)催化剂条件下,通过聚合反应合成聚醚酯多元醇.研究了各种类型起始剂对聚合反应的影响.发现起始剂中羟基的质量分数影响催化剂的活性,引发剂中羟基的质量分数越低,使用的催化剂的活性和效率越高.这源于催化剂和环氧丙烷的空位配合效应,且这种效应已经被多种起始剂所证实,而1,3,5-三(2-羟乙基)氰尿酸(THEIC)例外.研究还发现反应产生10％～15％的副产物碳酸丙烯酯.通过红外光谱和核磁共振氢谱确定了聚醚酯共聚物的结构.【期刊名称】《上海塑料》【年(卷),期】2014(000)004【总页数】4页(P22-25)【关键词】合成;聚醚酯多元醇;聚合反应;双金属氰化物催化剂;碳酸丙烯酯【作者】韩宏伟;朱丙清;顾尧【作者单位】青岛科技大学橡塑材料与工程教育部重点实验室,山东青岛266042;青岛科技大学橡塑材料与工程教育部重点实验室,山东青岛266042;青岛科技大学橡塑材料与工程教育部重点实验室,山东青岛266042【正文语种】中文【中图分类】TQ30 前言多元醇是聚氨酯合成工业中的一种主要原料，主要分为聚醚多元醇和聚酯多元醇。
多年来，研究人员一直致力于合成高分子链段中同时含有聚醚和聚酯的多元醇。
这种新型的多元醇既有聚醚也有聚酯的特征属性。
由聚醚酯多元醇制备的聚氨酯产品，不仅保持了聚醚链原有的低温柔顺性和耐水解性，同时还具有酯基的耐油性和力学性能。
最近几年，聚醚酯多元醇［1－2］的研究主要集中在环氧丙烷（PO）和二氧化碳（CO2）的共聚反应［3－4］上。
该反应同时生成含有醚键和酯键的聚碳酸酯。
当这种新型高分子的链末端含有羟基时，则被称为聚醚酯多元醇。
已有多种催化剂被用于合成这种多元醇，并且取得了一定成果［5］。
20世纪60年代，Jack M［6］发明了双金属催化剂。
该催化剂用于合成聚醚和聚酯［7－8］。
固相多肽合成树脂的特征和进展Camarero.JA和Cotton GJ等[14]报道，在一个3-巯基-3戊酮酰胺-PEG-聚-（N， N-二甲基丙烯酰胺）共聚物上载体（HS-PEGA）上，通过最优化的Boc-SPPS，可以从固相载体上直接得到未保护的多肽。
这种方法降低了操作中的损失，明显提高了整个的化学偶联效率。
他们合成了几个15-47个残基的肽，并且这种方法可以扩展到用来实现顺序的分子内络合，允许进入大得多的聚合肽和蛋白质系统。
[4] Chemical Approaches to the Synthesis of Peptide and Proteins，Paul Lloyd-Williams， Fernando Albericio， Ernest Giralt， 1997[5] Winger TM， Ludovice PJ， Chaikof EL， convenient rout to thiol terminated peptides for conjugation and surface functionalization strategies， Bioconjug Chem 1995 May-Jun;6(3);[6] Henning DS， Lajoie GA， Brown GR， St-Pierre LE，St-Pierre S，Polymer resins with amino acid containing pendants for sorption of biliubin. I. Comparison of Merrifield and polyamide resins， nt J Artif Organ 1984[7] Synthesis notes， 1996[8] Sparrow JT， Knieb-Cordonier NG， Objeyseskere NU， McMurrayJS ， Large-pore polydimethylacrylamide resin solid-phase peptide synthesis; applications in Fmoc chemistry， Pept Res 1996 Nov-Dec; 96(6);[9] Kanda P， Kennedy RC， Sparrow JT， Synthesis of polyamide supports for use in peptide synthesis and as peptide-resin conjugatesfor antibody production， Int J Pept Protein Res 1991 Oct;38(4);[10] Haynie SL， Crum GA Doele BA ， Antimicrobial activities of amphiphilc peptide covalently bonded to a water-insoluble resin，Antimicrob Agents Chemother 1995 Feb; 39(2);[11] Kates SA McGuinness BF， Blackburn C， etc，“high-load” polyethylene glycol-polystyrene( PEG-PS) graft supports for solid-phase synthesis， Biopolymers， 1998，4(3);[12] Auzanneau FI， Meldal M， Bock K， synthesis，Characterization and biocompatibility of PEGA resins， J.Pept Sci 1995Jan-Feb;1(1);[13] Renil M， Ferreras M ， Delaisee JM， Foged NT， Meldal M，PEGA supports for combinatorial peptide synthesis and solid-phase enzymatic library assays， J Pept Sci 1998 May ，4(3);[14] Camarero JA， Cotton GJ，Adeva A， Muir TW， Chemical ligation of unprotected peptides directly from a solid support， J Pept Res 1998Apr; 51(4);[15] Tegge W ， Frank R， Peptide synthesis on Sepharose beads， J Pept Res 1997 Apr;49(4);[16] Mcmurray JS， The use of polyacrylamide-based peptide synthesis resins for the generation of antipeptide antibodies，Biopolymers 1998，47(5);[17] Buettner JA， Dadd CA， Baumbach GA， Masecar BL， Hammond DJ， Chemically derived peptide libraries: a new resin and methodology for lead identification . Int J Pept Protein Res 1996 Jan-Feb;47(1-2);[18] Sebestyen F， SzendreiG， Mak M，etc， Coloured Peptides: synthesis， properties and use in preparation pf peptide sub-library kits， J Pept Sci， 1998 Jun， 4(4);[19] Mery J， Brugidou J， Derancourt J， Disulfide bond as peptide-resin linkage in Boc-Bzl SPPS.for potential biochemical applications， Pept Res 1992 Jul-Aug， 5(4);[20] Lloyd-Williams P， Albericio F， Giralt E， convergent solid-phase peptide synthesis.VIII.Synthesis， using a photolabile resin ，and purification of a methionine-containing protected peptide ， Int J Pept Protein Res 1991 Jan;37(1);[21] Englebretsen DR， Fmoc SPPS using Perloza beaded cellulose，Int J Pept Protein Res， 1994 Jun， 43(6);[22] Englebretsen DR， Harding DR， Solid-phase synthesis of a peptide-ligand affinity matrix for isolation of chymosin， Pept Res，1993 Nov-Dec， 6(6);[23] Zuckermann RN， Banville SC， Automated peptide-resin deprotection/cleavage by a robotic workstation， Pept Res 1992 Mar-Jun;5(3);。
目前 Au-Ag 合金纳米颗粒的合成方法主要包括：化学还原法[63-70]、电化学合成法[71]、微乳液法[72]、激光诱导法[73]、销蚀法[74]以及金银的原位置换反应法[75,76]等。
化学还原法是目前合成 Au-Ag 合金纳米颗粒的主要途径，其基本原理主要是在稳定剂(如表面活性剂和高分子聚合物等)的保护下，通过强还原剂同时还原金盐与银盐，从而形成 Au-Ag 合金纳米颗粒。
大多数情况下，在制备过程中 Au-Ag 合金纳米颗粒的成分与颗粒大小的均一度难以兼顾，容易得到大小均一但成分严重不均的纳米金属颗粒或者成分平均但颗粒大小分布较差的合金纳米颗粒。
Link 等人[59]以柠檬酸钠为保护剂兼还原剂，采用在加热回流的方法合成了粒径大小为 20 nm 的 Au-Ag而采用同样的方法合成的 Ag 纳米颗粒直径却远大于 20nm，这为我们比较合金和单金属的性质带来了不便。
此外，Chen 等人[77]在微乳液体系中，以水合肼为还原剂，制备得到的 Au-Ag合金纳米颗粒的粒径范围为 4-22nm，且随着合金颗粒中 Ag 摩尔比例的增加合金颗粒半径会明显增大。
保护剂的性质对贵金属纳米颗粒的物理和化学性质影响极大：以硫醇[78-80]为稳定合成的金属纳米颗粒表面趋向于形成一层高致密度的保护膜，阻碍反应物与金属颗粒的直接接触，致使合金纳米颗粒完全没有催化活性，而以聚乙烯吡咯烷酮(PVP)为保护剂制备的 Au-Ag 合金纳米颗粒对醇的选择性氧化反应有着比纳米 Au颗粒更高的催化活性[ 81,82 ]。
采用四烷基铵盐为稳定剂制备纳米级合金颗粒时溶胶的稳定性较差，颗粒容易在较短时间内团聚成大颗粒而丧失纳米材料的特性[83]。
许多实验证明，以柠檬酸钠为保护剂制备得到的Au-Ag 合金纳米颗粒直径(15~20 nm)往往大于以高分子聚合物为保护剂制备的金属颗粒。
王爱琴课题组采用 CTAB 为稳定剂，NaBH4为还原剂分别开发了一步法和两步法来制备具有良好抗烧结性的负载型 Au-Ag 合金纳米颗粒并将其成功应用于CO 的催化氧化反应。
介绍材料科学与工程专业的英语作文英文回答：Materials science and engineering (MSE) is an interdisciplinary field that deals with the design, synthesis, characterization, and application of materials. MSE graduates possess a strong foundation in chemistry, physics, and mathematics, enabling them to understand the behavior of materials at the atomic and molecular levels. They also have expertise in materials processing and manufacturing, allowing them to optimize the performance of materials for specific applications.MSE is a rapidly growing field with applications in a wide range of industries, including aerospace, automotive, electronics, and healthcare. MSE graduates are highly sought-after by employers for their problem-solving abilities, technical skills, and interdisciplinary knowledge.中文回答：材料科学与工程（MSE）是一个跨学科领域，涉及材料的设计、合成、表征和应用。
Development of drug loaded nanoparticles for tumor targeting. Part 1: Synthesis, characterization, and biological evaluation in 2D cell culturesSupporting InformationMohammad H. El-Dakdouki;a,c Ellen Puré;b Xuefei Huang a*a Department of Chemistry, Chemistry Building, Room 426, 578 S. Shaw Lane, Michigan State University, East Lansing, MI 48824, USAb The Wistar Institute, Room 372, 3601 Spruce Street, Philadelphia, PA 19104, USAc Current Address: Department of Chemistry, Beirut Arab University, Beirut, LebanonTel: +1-517-355-9715, ext 329Fax: +1-517-353-1793Email: ********************.eduTable of ContentI. Experimental procedures1.1. Synthesis of SNP S31.2. Synthesis of HA-SNP S31.3. Synthesis of DOX-HA-SNP S41.4. Kinetics of HA-SNP uptake by laser confocal microscopy S51.5. Kinetics of HA-SNP uptake by flow cytometry S51.6. Determination of cellular uptake by flow cytometry S61.7. Energy-dependent uptake of HA-SNP S61.8. Examining the uptake of HA-SNP in the presence of β-CD S71.9. In vitro release of DOX from DOX-HA-SNP S71.10. Monitoring the uptake of DOX and DOX-HA-SNP by confocal microscopy S8II. Supporting figures and tablesFig. S1. Characterization of SNPs S9 Table S1. Table summarizing characteristics of various SNPs S10 Fig. S2. NMR spectra of DOX, HA, and DOX-HA-SNP S11 Fig. S3. TEM images for cells incubated with HA-SNPs S12I. Experimental procedures1.1. Synthesis of the FITC-doped silica nanoparticles (SNP)FITC-APTES conjugate was synthesized by reacting FITC (12.3 g, 0.032 mmol) and APTES (70 mg, 0.32 mmol) in ethanol (1 ml) for 18 h at room temperature in the dark to avoid photo-bleaching. A water/oil microemulsion was prepared by stirring a mixture of cyclohexane (7.7 ml), Triton® X- 100 (1.77 g), n-hexanol (1.6 ml), and DI water (0.34 ml) in a 50 ml round bottom flask for 20 minutes. The fluorescent core was formed by polymerizing the FITC-APTES conjugate (100 µl) using 30% NH4OH (200 µl) and stirring the mixture for 6 h. TEOS (200 µl) was added and the mixture was stirred for 18 h. The surface of the NPs was decorated with amino groups by adding APTES (50 µl) and 30% NH4OH (50 µl) and stirring the mixture for 6 h. THPMP (20 µl) was added and the mixture was stirred for 18 h. The SNPs were precipitated by adding ethanol (50 ml) and collected by centrifugation. The nanoparticles were repeatedly washed and centrifuged with ethanol (5 x 30 ml) and water (3 x 30 ml). The washing steps were associated with sonication to remove any adsorbed FITC. SNP (45 mg) was produced, and its fluorescence properties assessed by UV-vis and fluorescence spectroscopy. 1.2. Synthesis of HA-SNPHA (31 kDa) (50 mg) in its acid form, was dissolved in dd water (3ml) by sonication followed by the dropwise addition of acetonitrile (2 ml). NMM (15 µl) was added and the solution was cooled to 4o C in an ice bath. CDMT (15 mg) was added and the mixture was stirred at room temperature for 2 h to activate the carboxylic acid groups on HA. SNP (15 mg) was added and the mixture was stirred at room temperature for 72 h. The pH was then adjusted to 7 using Amberlite H+. The mixture was filtered and diluted by adding dd water and purified by ultrafiltration (MWCO 100,000) to remove the excess starting material and side products. HA-SNP (55 mg) was collected with its fluorescence properties assessed by UV-vis and fluorescence spectroscopy.1.3. Synthesis of DOX-HA-SNPTo a solution of FITC-doped HA-SNP (15 mg) dispersed in dd water (10 ml) was added ADH (75 mg), and the pH was adjusted to 4.5-5 by the addition of 0.1 N aqueous HCl solution. EDCI (2 mg) was added and the solution was stirred at room temperature for 4 h during which the pH was maintained between 4.5 and 5. The pH was then adjusted to 7 using 0.1 N aqueous NaOH solution. The ADH-functionalized HA-coated nanoparticles (ADH-HA-SNP) were collected by centrifugation and washed with dd water (5 times) to remove the undesired reagents. After the final wash, the nanoparticles were resuspended in 0.1 M acetate buffer (pH 6.0, 5 ml) and sonicated for 30 minutes. DOX (3 mg), dissolved in the same acetate buffer (3 ml), was added and the solution was stirred at room temperature for 48 hours in the dark. The nanoparticles were then collected by centrifugation and washed with water (5 times). Each wash was accompanied with sonication to ensure the removal of any adsorbed DOX. The collection of orange-colored nanoparticles suggested the successful conjugation of DOX on the nanoparticles (See Figure 1c in main text). The concentration of the prepared stock solution of DOX-HA-SNP was 0.85 mg-NP/ml. The amount of conjugated DOX was assessed by UV-vis spectroscopy. To eliminate the interference from FITC, equivalent amount (by mass) of FITC-doped HA-SNP was used to collect a baseline that was then subtracted from the DOX-HA-SNP reading. The percentage of DOX on the surface of nanoparticles was calculated to be 0.6% (w/w) as follows: A=E b C DOX; 0.12= 12500 x 1 x C DOX; C DOX= 9.6 x 10-6 MIn 100 µl stock solution: m DOX= C x V x M= 9.6 x 10-6 M x 0.1 x 10-3 L x 543.52 mol/L;m DOX= 0.520 x 10-6 g =0.520 x 10-3 mg; In 1 ml stock solution: [DOX]= 5.20 x 10-3 mg/mlThe percentage of DOX (w/w) on NPs: % DOX on SNPs= [(5.09 x 10-3)/0.85] * 100; %DOX (w/w) =0.6%1.4. Kinetics of HA-SNP uptake by laser confocal microscopySKOV-3 cells (2 x 105 cells/well) were cultured in a 4-well chambered plate at 37o C and 5% CO2for 24 h. The culture media was removed and the cells were washed with PBS (2 times). HA-SNP nanoparticles (working concentration: HA-SNP: 42 µg/ml; 1 ml) in serum-free DMEM were added. The cells were incubated with the nanoparticles for desired time. The supernatant was removed. The cells were washed twice with PBS, and fixed with 10% formalin (0.5 ml/well) for 15 min. Formalin was removed and the cells were washed twice with PBS. DAPI (300 nM, 300 µl/well) were added, and the cells were incubated for 4-5 min. DAPI solution was removed, and the cells were washed with PBS and dd water. The plate was covered by an aluminum foil and stored at 4o C till imaging time. Images were gathered on an Olympus FluoView 1000 LSM confocal microscope.1.5. Kinetics of HA-SNP uptake by flow CytometrySKOV-3 cells (2 x 105 cells/well)were allowed to attach in a 24-well plate overnight at 37o C and 5% CO2. The cells were washed twice with PBS, and HA-SNP were added (working concentration: HA-SNP: 42 µg/ml; 1 ml) in serum-free DMEM were added. The plate was incubated for desired time at 37o C and 5% CO2. The cells were then washed with PBS (3 times) and trypsinized with 0.25% trypsin-EDTA (0.5 ml/well). Trypsin was neutralized with serum-containing DMEM (5 times), and the cells were collected by centrifugation (2500 rpm; 4o C).The cells were resuspended in serum-containing DMEM (300 µl) and transferred to FACS tubes. The cells were stored on ice till the time of FACS analysis.1.6. Determination of cellular uptake of SNP by flow cytometrySKOV-3 cells (2 x 105 cells/well)were allowed to attach in a 24-well plate overnight at 37o C and 5% CO2. The cells were washed twice with PBS, and nanoparticles of equivalent fluorescence were added (working concentration: SNP: 27 µg/ml; HA-SNP: 104 µg/ml) in serum-free DMEM were added. The plate was incubated for 18 h at 37o C and 5% CO2. The cells were then washed with PBS (3 times) and trypsinized with 0.25% trypsin-EDTA (1 ml). Trypsin was neutralized with serum-containing DMEM (5 times), and the cells were collected by centrifugation (2500 rpm; 4o C). The cells were resuspended in serum-containing DMEM (300 µl) and transferred to FACS tubes. The cells were stored on ice till the time of FACS analysis. Propidium iodide (PI) (100 µg/ml, 3.3 µl) was added at the time of analysis.1.7. Energy-dependent uptake of HA-SNPSKOV-3 cells (2 x105 cells/plate) were cultured in five 35 mm cell culture plates over night at 37o C and 5% CO2. The supernatant was removed and the cells were washed twice with PBS. Two plates received SNP (47.5 µg/ml, 1ml) while another two plates received HA-SNP (21.25 µg/ml, 1ml). The fifth plate received serum free-DMEM and was used as a control. One set of SNP and HA-SNP-receiving plates was incubated at 37o C while the other set was incubated at 4o C for 3 h. The nanoparticles were removed and the cells were washed thoroughly with PBS (5 times). The cells were collected using trypsin (0.5 ml/plate) and centrifugation (2500 rpm, 4o C). The cells were washed with serum containing DMEM and centrifuged four times. The cells were resuspended in serum containing DMEM (400 µl), and stored on ice till time of analysis. FITC fluorescence was assessed on a flow cytometer.1.8. Examining the uptake of HA-SNP in the presence of β-CDSKOV-3 cells (2 x105 cells/plate) were cultured in 24-well cell culture plate over night at 37o C and 5% CO2. The culture medium was removed and the cells were washed with PBS. Some cells were incubated with β-cylcodextrin (5 mM, 1ml) in serum-free medium for 1 h. Other cells received serum-free medium (1ml). HA-SNP (1.7 mg/ml; 10 µl) was then added to all cells (except negative control well), and the plates were incubated at 37o C for 2 h. The cells were washed with PBS, collected using trypsin (300 µl/well), and washed with serum-containing medium. The cells were finally suspended in serum-containing DMEM, transferred to FACS tubes, and stored on ice till analysis time. Propidium iodide (PI) (10 0 µg/ml, 4 µl/tube) was added right before analysis.1.9. In vitro release of DOX from DOX-HA-SNPEqual amounts of lyophilized DOX-HA-SNP (0.45 mg) were suspended in PBS (pH 7.4) or PBS (pH 4.5) to a final volume of 1 ml. At specific time points, the tubes were centrifuged. 100 µl samples of the supernatant were drawn from each tube and transferred to a 96 well black plate (clear bottom). The release of DOX was assessed by measuring the intrinsic fluorescence of DOX on a plate reader (excitation wavelength 483 nm, emission wavelength 580 nm). When the measurement was done, the samples were returned to their respective tubes. To determine the total amount of DOX in the sample, 6N HCl (1.3 ml) was added to the nanoparticles to release the cargo. The amount of DOX that remained was determined by measuring fluorescence of the resulting solution. The fluorescence of unreleased DOX was added to that of the highest measured released DOX. The percentage of DOX released at a given time point is: % DOX released = [(Fluorescence of released DOX)/Total fluorescence] x 1001.10. Monitoring the Uptake of DOX and DOX-HA-SNP by confocal microscopySKOV-3 cancer cells (2 x 105 cells/well) were cultured in a 4-well plate and incubated at 37o C and 5% CO2 overnight. The supernatant was removed and the cells were washed. DOX-HA-SNP (40 µg-NP/ml; 1 ml) or the equivalent amount of DOX was added to two wells. A third well did not receive NPs or DOX and served as a control. The cells were incubated for 18 h. The supernatants were then removed and the cells were washed with PBS four times, fixed with formalin (0.5 ml/well) for 15 min, and washed again with PBS twice. DAPI (300 nM, 300 µl/PBS) was added to the cells for 5 min, followed by washing the cells with PBS and DI water twice each. The plate was covered with aluminum foil and stored at 4o C in the dark till imaging time. Images were collected on an Olympus view microscope.III. Supporting figures and tablesa)b)FITC-PEG-SNP 304050607080901005001000W e i g h t (%)Temperature (o C)HA-SNPSNP77.9%54.1%c)0.050.10.150.2380480580680780A b s o r b a n c e (a .u .)Wavelength (nm)HA-SNPDOX-HA-SNP0.20.40.60.811.21.41.6b-HA/CD44+(b-HA+HA)/CD44+b-HA/CD44-A b s o r b a n c e (a .u .)d)Fig. S1. Characterization of SNPs; (a) TEM of SNP (scale bar 50 nm) and HA-SNP (scale bar 100 nm); (b) TGA supporting the successful immobilization of HA on the surface of SNP. The percentage of HA coating on SNP was 31%. (c) UV-vis spectra of DOX-HA-SNP and HA-SNP at the same NP concentration. (d-e) Competitive ELISA assay demonstrating the HA polymer retained its intrinsic binding to CD44 after conjugation to SNP. (d) HA (31 kDa) polymer competed with biotinylated HA (b-HA) for binding with CD44. Maximum absorbance was obtained when b-HA was added to CD44 positive wells (b-HA/CD44+). However, minimal signal was collected in the absence of CD44 (b-HA/CD44-). When HA polymer was added with b-HA, the binding of the latter dropped dramatically (b-HA+HA/CD44+).HA loading calculation based on TGA dataSNP has 77.9% by weight the inorganic core and 22.1% the organic coating from the TGA weight loss. Upon HA immobilization, the weight of the total organic coating increased to 45.9%. Solving equation (0.221+x)/(0.221+0.779+x) = 0.459 gave x a value of 0.44. Thus, the weight of HA on HA-SNP was 0.440/(0.587+0.413+0.44)*100% = 31%.Table S1. Summary of the hydrodynamic radii, polydispersity indices (PDI), zeta potentials, and TGA data for SNP, HA-SNP, and DOX-HA-SNP. ND: not determined. The TGA data was not collected for DOX-HA-SNP due to the small weight change from DOX immobilization (0.6% w-DOX/w-NP by UV-vis).b)1.89 ppmnc)d)DOX-HA-SNP7.11 ppm5.37 ppm Fig. S2. NMR spectra of free DOX (a), free HA polymer (b), and DOX-HA-SNP (c). The inset box in (c) is expanded in spectrum (d) to show the characteristic peaks of DOX at 7.11 ppm and 5.37 pm (see spectrum (a) for comparison). Note that the anomeric protons from HA, shown at 4.3 ppm and 4.45 ppm in spectrum (b) did not show up in the spectrum of DOX-HA-SNP due to the suppression of the water peak. The NMR spectra were used to confirm the successful conjugation of DOX onto NPs. An accurate quantification of DOX loading on NPs was assessed from UV-vis absorbance spectra which indicated 0.6% loading (w-DOX/w-NP).Fig. S3. TEM images of two different SKOV-3 cells incubated with HA-SNP followed by thorough washings. The images clearly indicate that SNPs are localized inside the cells and not on the surface.。
sci中的长难句在科学论文中，长难句常常出现，主要是为了表达复杂的概念和关系。
以下是一些常见的长难句例子：1. "The development and implementation of a robust and scalable machine learning algorithm, combined with advanced data analytics techniques, have significantly improved the accuracy and efficiency of predicting and analyzing complex biological systems, thereby enabling researchers to gain deeper insights into the underlying mechanisms driving disease progression."“强大且可扩展的机器学习算法的开发和实施，结合先进的数据分析技术，显著提高了预测和分析复杂生物系统的准确性和效率，从而使研究人员能够更深入地了解驱动疾病进展的潜在机制。
”2. "The integration of nanomaterials with traditional construction materials, such as concrete and steel, not only enhances their mechanical properties, but also provides additional functionalities, such as self-healing, self-cleaning, and energy harvesting capabilities, contributing to the development of sustainable and smart infrastructure."“将纳米材料与混凝土和钢材等传统建筑材料相结合，不仅增强了它们的机械性能，还提供了额外的功能，如自我修复、自清洁和能量收集能力，有助于可持续和智能基础设施的发展。
