Structure, photocatalytic and antibacterial activity study of Meso porous Ni and S co-doped TiO2 nano material under visible light irradiation

Undoped and Ni–S co-doped mesoporous TiO2 nano materials were synthesized by using sol–gel method.The characteristic features of as prepared catalyst samples were investigated using various advanced spectroscopic and analytical techniques.The characterization results of the samples revealed that all the samples exhibited anatase phase(XRD),decreasing band gap(2.68 eV)(UV–Vis-DRS),small particle size(9.2 nm)(TEM),high surface area(142.156 m^2·g^-1)(BET),particles with spherical shape and smooth morphology(SEM);there is a frequency shift observed for co-doped sample(FT-IR)and the elemental composition electronic states and position of the doped elements(Ni and S)in the TiO2 lattice analyzed by XPS and EDX.These results supported the photocatalytic degradation of Bismarck Brown Red(BBR)achieved with in 110 min and also exhibited the antibacterial activity on Staphylococcus aureus(MTCC-3160),Pseudomonas fluorescence(MTCC-1688)under visible light irradiation.

Preparation, Characterization and Antibacterial Property of Cerium Substituted Hydroxyapatite Nanoparticles

Nanoparticles of hydroxyapatite （HAP） and cerium substituted hydroxyapatite （CeHAP） with the atomic ratio of Ce/[ Ca ＋ Ce] （xco） from 0 to 0.2 were prepared by sol-gel-supercritical fluid drying （SCFD） method. The nanoparticles were characterized by TEM, XRD, and FT-IR, and the effects of cerium on crystal structure, crystallinity, and particle shape were discussed. With the tests of bacterial inhibition zone and antibacterial ratio, the antibacterial property of HAP and CeHAP nanoparticles on Escherichia coli, Staphylococcus aureus, Lactobacillus were researched. Results showed that the nanoparticles of HAP and CeHAP could be made by sol-gel-SCFD, cerium could partially substitute for calcium and enter the structure of HAP. After substitution, the crystallinity, the IR wavenumbers of bonds in CeHAP decreased gradually with increase of cerium substitution, and the morphology of the nanoparticles changed from the short rod-shaped HAP to the needle-shaped CeHAP. The nanoparticles of HAP and CeHAP with Xco below 0.08 had antibacterial property only forcibly contacting with the test bacteria at the test concentration of 0.1 g · mi^-1, however, the Ce- HAP nanoparticles had antibacterial ability at that concentration no matter statically or dynamically contacting with the test bacteria when Xco was above 0.08, and the antibacterial ability gets better with the increase Of Xce, indicating that the antibacterial property was improved after calcium was partially substituted by cerium. The improved antibacterial effects of CeHAP nanoparticle on Lactobacillus showed its potential ability to anticaries.

Synthesis,Characterization and Antibacterial Property of Strontium Half and Totally Substituted Hydroxyapatite Nanoparticles

Nanoparticles of hydroxyapatite（HAP）, strontium half substituted hydroxyapatite （SrCaHAP） and strontium totally substituted hydroxyapatite （SrHAP） were prepared by sol-gel-supercritical fluid drying （SCFD） method. The nanoparticles were characterized by element content analysis, FT-IR, XRD and TEM, and the effects of strontium substitution on crystal structure, crystallinity, particle shape and antibacterial properties of the nanoparticles on Escherichia coli, Staphylococcus aureus, Lactobacillus were researched. Results show that strontium can half and totally substitute for calcium and enter the structure of apatite according to the initial atomic ratios of Sr/[Sr＋Ca] as 0.5, 1. The substitution decreases the IR wavenumbers of SrCaHAP and SrHAP, and changes the morphology of the nanoparticles from short rod shaped HAP to needle shaped SrCaHAP, and back to short rod shaped SrHAP. The crystallinity of HAP is higher than that of SrCaHAP, but is lower than that of SrHAP. Moreover, the antibacterial property of SrCaHAP and SrHAP are improved after the calcium is half and totally substituted by strontium.

Preparation of TiO_2 Thin Film and Its Antibacterial Activity

TiO 2 nanometer thin films with photocatalytic antibacterial activity were prepared by the sol-gel method on fused quartz and soda lime glass precoated with a SiO 2 layer.The thin films were characterized by X-ray photoelectron spectroscopy (XPS),scanning electron microscopy (SEM),and X-ray diffraction (XRD).The results show that sodium and calcium diffusion into nascent TiO 2 film is effectively retarded by the SiO 2 layer precoated on the soda lime glass.The antibacterial activity of the films was determined.The crystalline of TiO 2 nanometer thin film has important effects on the antibacterial activity of the film.

Preparation of UV-curable Nano-silver Antimicrobial Agent and Its Application in Non-woven Fabric

Nano-silver and waterborne polyurethane(WPU)composite emulsion was synthesized.The average diameter of silver nanoparticles(SNPs)was about 20 nm,and the average diameter of WPU was 101.32 nm.The anti-bacteria finishing of a polypropylene non-woven fabric(NWF)was carried out by ultraviolet finishing technology and the double dipping twin-roll method.The standard AATCC100 was used to test the antimicrobial activity of the samples.The results showed that the antimicrobial rates of Klebsiella pneumoniae(K.pneumoniae)and Staphylococcus aureus(S.aureus)were above 90%,which indicated that the NWF finishing had good antimicrobial activity.In addition,the thermal stability,mechanical properties,whiteness and contact angle of antimicrobial finishing nonwovens were characterized.The results showed that the performance of antimicrobial nonwovens was stable at 300℃.The breaking strength was better than that of untreated nonwovens,and the contact angle reached 119.1°.

Nano-silver-modified polyphosphazene nanoparticles with different morphologies:Design,synthesis,and evaluation of antibacterial activity

Drug-resistant bacteria present a severe threat to public health,emphasizing the importance of developing broad-spectrum antibacterial agents that are free from drug resistance.Among silver-based antibacterial agents,nano-silver has been found to exhibit the most promising and comprehensive performance.The exploration of the antibacterial capacity and morphological changes of silver nanoparticles(AgNPs)could offer a starting point for the development of safe and efficient antibacterial agents.In this study,three types of nano-silver-modified polyphosphazene(PRV)nanoparticles with different morphologies were synthesized using precipitation polymerization.These nanoparticles were characterized using various techniques,including Fourier-transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),and thermogravimetric analysis(TGA).The antibacterial activity of these nanoparticles against Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)was assessed using minimum inhibitory concentration(MiC)/minimum bactericidal concentration(MBC)tests and inverted fluorescence microscopy.Our results revealed that the antibacterial activity of silver nanoparticles can vary significantly depending on their immobilized form.Ag@PRV Strawberry-like nanoparticles(NPs)exhibited higher antibacterial activity compared to Ag@PRV Yolk-Shell NPs and Ag@PRV Cable-like nanofibers(NFs).Notably,all three types of synthesized nanoparticles demonstrated a stronger bactericidal effect on Gram-positive bacteria than Gram-negative bacteria.Live/dead bacterial staining and scanning electron microscopy demonstrated that silver can kill bacteria by altering the permeability of their cell membranes.These findings offer valuable insights for designing and practically applying new silver-based antibacterial agents in the future.

Influence of Modified ZnO Quantum Dots and Nanostructures as New Antibacterials

Antibacterial activities of various spherical zinc oxide nanoparticles and nano special morphological structures including quantum dots, nanorod arrays, nanoporous shapes and needle-like crystals had been investigated as new nanomedicine compounds. Also antibacterial activity based on minimal inhibitory concentration and the growth inhibitory zone (well method) was evaluated. ZnO nanostructures were fabricated by novel hydrolysis sol-gel-hydrothermal process followed with rapid quenching as new technique using glycerine, vegetable fatty esters such as coconut, sunflower and Lauric alcohol ethoxylated as organic templates soluble in eco-friendly nanofluids. The results showed that Bacillus anthracis and Pseudomonas aerogenes were extremely sensitive to treatment with unique ZnO nanostructured. Their growth inhibitory zone presented 30 mm and 25 mm inhibition zone with better inhibitory effect compared to the Gentamicin antibiotic standard. ZnO nanostructures had also been indicated to have a wide range of antibacterial activities against both Gram-positive and Gram-negative bacteria especially more effective on (gr+) species using the growth inhibitory zone. We could design and make significant formulations of fatty acids and esters-capped ZnO quantum dots nanofluids which created high promising agents for controlling Anthrax, Staphylococcus epidermidis and their influences in antimicrobial properties with low cost for future.

葡甘露聚糖抑菌护理凝胶的制备、抗HPV 16活性以及分子对接研究

葡甘露聚糖抑菌护理凝胶(Glucomannan antibacteria care gel,GACG)是本课题组开发的一款已上市的治疗女性阴道炎症的抑菌护理剂。本文介绍了GACG的制备工艺,通过建立高危型HPV 16假病毒感染人胚肾293FT细胞模型,重点研究GACG的主要活性成分白芨葡甘露聚糖、积雪草总苷和蛇床子精油对高危型人乳头瘤病毒16(Human papillomavirus type 16,HPV 16)的抗病毒作用。研究发现积雪草总苷和蛇床子精油对高危型HPV 16假病毒具有明显的抗病毒活性,分子对接进一步探究了积雪草苷、羟基积雪草苷以及蛇床子素对HPV 16抑制的可能机制。

Fe_2O_3-Al_2O_3-SiO_2-TiO_2抗菌、纳米湿敏陶瓷薄膜的Sol-Gel制备

利用溶胶凝胶法制成了Fe2O3-Al2O3-SiO2-TiO2抗菌、纳米湿敏陶瓷薄膜。用扫描电镜和原子力显微镜对膜的表面形貌和显微结构进行表征,分析了处理方式对膜的表面形貌和微观结构的影响。制成的Fe2O3-Al2O3-SiO2-TiO2抗菌、纳米湿敏陶瓷薄膜具有广谱抗菌、高效、无毒、持久和耐热等特点。湿敏特性测试结果表明:Fe2O3-Al2O3-SiO2-TiO2抗菌、纳米陶瓷薄膜制品的感湿灵敏度高,具有较好的响应特性和稳定性。

3种植物精油对调理牛排优势腐败菌的抑菌性

为明确调理牛排的优势腐败菌并筛选出抑菌性、专一性强的植物精油,通过传统培养基法结合聚合酶链式反应-变性梯度凝胶电泳技术筛选出调理牛排的优势腐败菌,并通过抑菌圈、最小抑菌浓度、最小杀菌浓度及细菌生长曲线,从丁香精油、豆蔻精油、黑胡椒精油中选出抑菌性最强的植物精油。结果表明:优势腐败菌为深蓝紫色杆菌(Janthinobacterium lividum)、恶臭假单胞菌(Pseudomonas putida)和热杀索丝菌(Brochothrix thermosphacta);丁香精油的抑菌圈直径均大于10 mm,2~4μL/mL的精油添加量就能明显抑制优势腐败菌的生长繁殖;豆蔻精油抑菌性稍弱;黑胡椒精油对3株优势腐败菌均无明显抑菌效果。

负载葡萄籽多酚海藻酸钠冻干凝胶的制备及其抗菌止血性能

以海藻酸钠(SA)、葡萄籽提取物(GSE)、Fe3+为原料,经过两次冷冻干燥得到冻干凝胶SA/GSE/Fe3+(SGF(0.75)),并通过体外实验探究SGF(0.75)冻干凝胶的孔隙率、吸水率、光热特性、抗菌性能、生物相容性及止血性能。结果表明,SGF(0.75)的孔隙率约37%,吸水率约1500%。在近红外激光照射下,SGF(0.75)可以杀死近90%的金黄色葡萄球菌和91%的大肠杆菌。止血性能实验表明,与纱布相比,SGF(0.75)失血量和止血时间分别减少了31%和66%。SGF(0.75)冻干凝胶止血能力强,抗菌效果好,且生物相容性好,安全性高,能促进伤口组织的愈合。

壳聚糖的提取与抗菌凝胶制备的实验教学设计

壳聚糖是甲壳素脱乙酰化后的产物,由于它具有良好的生物相容性和抗菌能力,被广泛用于抗菌消毒、药物递送等生物医用领域。本科普实验基于废物利用的可持续发展理念,选用生活中常见的厨余垃圾虾壳为原料,完成了对虾壳中甲壳素的提取与壳聚糖的制备。并通过一系列表征手段对文章中的观点加以佐证,同时根据本实验制备的壳聚糖衍生出一种壳聚糖抗菌消毒凝胶。我们采用梯度科普方案,让幼儿园小朋友及小学生、广大青少年、大学生与社会公众感受到化学的魅力所在,激发他们学习化学知识的兴趣,并在最后呼吁大家一起摒弃成见,重新审视化学,以更加深远的眼光领略化学之妙。

银离子抗菌凝胶联合精细护理对面部烧伤后瘢痕整形患者术后恢复的影响

目的:探究银离子抗菌凝胶联合精细面部护理对面部烧伤后瘢痕整形患者色素沉着、瘢痕及心理弹性的影响。方法:选取2020年1月-2022年1月笔者医院收治的82例面部烧伤后瘢痕整形患者为研究对象,按随机数字表法分为联合组和常规组各41例。常规组进行一般治疗并实行精细面部护理,联合组在此基础上加用银离子抗菌凝胶治疗,比较两组术前、术后3个月面部色素沉着面积及严重程度评分、瘢痕增生情况、焦虑自评量表(SAS)、抑郁自评量表(SDS)及心理弹性量表(CDRISC)评分。结果:术后3个月两组面部色素沉着面积及严重程度评分均下降,且联合组低于常规组(P<0.05);术后3个月联合组温哥华烧伤瘢痕评定量表(VSS)评分低于常规组(P<0.05);术后3个月两组SAS、SDS评分均下降,且联合组低于常规组(P<0.05);术后3个月两组坚韧度、力量性、乐观性3个维度评分及CD-RISC总评分均升高,且联合组高于常规组(P<0.05)。结论:银离子凝胶联合精细面部护理有利于缓解面部烧伤后瘢痕整形患者色素沉着症状,减少瘢痕形成,改善患者消极心理状态,提升心理弹性,促进患者身心健康。

一种新型气凝胶材料在新生儿PICC中的应用研究

针对传统医用粘胶敷料止血抗菌效果差的问题,提出一种改良的新型气凝胶材料制备,并对其性能进行研究。试验结果表明,气凝胶基体应变为90%时,应力为0.35 MPa;溶胀平衡时间为32 h,溶胀度为25;药物释放时间为36 h,药物累计释放量为75%;凝血指数约为0.2;与小鼠成纤维细胞共同培养96 h后,细胞存活率为100%,满足医学敷料的基础要求。通过在气凝胶基体内外层分别构建疏水防污层和氧化锌纳米线抗菌层,可有效避免材料过度吸收血液而引起的血液大量流失;抗菌层对大肠杆菌和金黄色葡萄杆菌的抑菌圈直径分别为(11.64±1.24)mm和(13.59±0.68)mm,抑菌效果良好。

环境友好型改性甲壳素吸附剂对苯扎氯铵的吸附与抑菌性能研究

采用蟹壳为原料制备改性的环境友好型改性甲壳素吸附剂,考察了吸附剂对抑菌消毒剂苯扎氯铵(BACs)的吸附影响因素,并制备了改性甲壳素包裹苯扎氯铵凝胶,考察凝胶对金黄色葡萄球菌、大肠杆菌、腐败菌的抑菌效果。研究结果表明,制备的改性甲壳素吸附剂表面存在大量松散的孔隙结构,具有很强的吸附能力。改性甲壳素吸附剂可以作为来源、酸碱性不同的BACs吸附剂,对BACs浓度范围在2.5 mg/L~80 mg/L的溶液中的BACs都具有非常快速而高效的吸附作用。吸附BACs所制备的ICH-BAC水凝胶对金黄色葡萄球菌、大肠杆菌、腐败菌等都具有非常好的离体抑菌活性。

明胶/羟丙基-β-环糊精/甘油-水复合凝胶的合成及其载药抗菌性能

目的 合成明胶/羟丙基-β-环糊精/甘油-水复合凝胶,探讨羟丙基-β-环糊精对该凝胶体系的影响及凝胶载药应用。方法 采用溶胶-凝胶法制备凝胶,并使用多种物理方法如扫描电子显微镜(SEM)、差示扫描量热法(DSC)、傅里叶红外光谱(IR)、X射线衍射(XRD)、流变学等方法对复合凝胶进行表征;以牛津杯法验证该凝胶递送左氧氟沙星的抗菌效果。结果 羟丙基-β-环糊精以氢键结合明胶,促进明胶分子螺旋微结构聚集,增强了复合凝胶的稳定性,流变测试可知该复合凝胶应力屈服值增大了1000Pa。复合凝胶装载抗菌药物左氧氟沙星后作用于金黄色葡萄球菌和大肠埃希氏菌,抑菌效能可分别达到对照标准的90.27%和80.02%。结论 新型复合凝胶合成方法简便、易行,体系中的羟丙基-β-环糊精和甘油都可改善复合凝胶的微结构、性质和性能,该复合凝胶的左氧氟沙星制剂表现出极好的抑菌效果。

苦杏仁抑菌肽的筛选富集及结构鉴定

为探究苦杏仁抑菌肽的制备、富集及结构分析,本实验以苦杏仁为原料,在脱脂后提蛋白,使用酶法制备苦杏仁蛋白抑菌肽,优化制备工艺,检测抑菌肽的抑菌活性,进一步纯化富集,分离出抑菌活性最强的抑菌肽组分并对其进行结构分析。结果表明,木瓜蛋白酶酶解物对于革兰氏阳性菌尤其是金黄色葡萄球菌的抑菌作用最强。优化苦杏仁抑菌肽的制备工艺最佳条件为:酶解温度为74℃,酶底比为2.5%,pH为7。得到抑菌肽的蛋白浓度为19.21%,并测得最低抑菌浓度为3.13 mg/mL。利用超滤和凝胶过滤色谱(Sephadex G-25)对抑菌肽进行分离纯化,从中筛选出肽组分A-II-b对金黄色葡萄球菌的抑制活性最强。将凝胶过滤条件优化为:样品浓度9.38 mg/mL,洗脱速度0.68 mL/min、洗脱剂为纯水。在此条件下测得肽组分A-II-b的峰面积比为13.15%。采用液相色谱-质谱联用技术对肽组分A-II-b进行结构分析,将结果导入Uniprot数据库与APD3数据库进行匹配,筛选出7种分子量在1500~2500 Da的潜在具有抗菌活性的苦杏仁肽序列,分别是ALPDEVLQNAFRIS、ESWNPRDPQFQWAGVA、VAYWSYNNGEQPLVA、FLDLSNDQNQLQLDQVPR、GENDNRNQIIRVR、RNLQGE NDNRNQIIRVR和RALPDEVLQNAFRIS。本研究促进了杏仁活性肽的深度开发和资源再利用,同时也为其作为抑菌肽的研究和进一步开发利用提供理论依据。

Development of Topical Antimicrobial Gel Containing Beehive Extract

This study aimed to determine the antimicrobial activity of beehive extract and developed topical antimicrobial gel. The beehives were extracted with three different solvents： distilled water, 50% ethanol and 95% ethanol, then each filtrate was evaporated by vacuum rotary evaporator to obtain crude extracts： water extract （W）, water-ethanol extract （WE） and ethanol extract （E）. These extracts were tested for their antimicrobial activity against five bacterial strains： Escherichia coli （ATCC 25922）, Psuedomonas aeuruginosa （ATCC 27853）, Staphylococcus aureus （ATCC 25923）, Methicillin Resistance Staphylococcus aureus （MRSA） and β-hemolytic Streptococcus group A （GAS）, then they were evaluated for their MIC and MBC values. The results revealed that the yield of the W, WE and E extracts amounted to 16.25%, 14.42% and 6.67%, respectively. Whereas, all of the samples were found to be effective against P. aeuruginosa, S. aureus, MRSA and GAS, but they were ineffective against E. coli. The W extract exhibited the highest antimicrobial activity with MIC values of 31.25-62.50 mg/mL and MBC values of 62.50 mg/mL. Then the gel bases using different gelling agents such as carbopol, hydroxyethylcellulose （HEC） and hydroxypropyl methylcellulose （HPMC） were formulated and evaluated for their physical properties： appearance, texture, pH, spread ability and stability. The formula which contained HEC was selected to incorporate with the W extract due to its smooth texture, good spreadability on the skin and good stability. The W gel exhibited a promising antimicrobial activity in both before and after stability test and also expressed no skin irritation.

四妙勇安汤联合纳米银抗菌凝胶治疗糖尿病足临床研究

目的观察四妙勇安汤联合纳米银抗菌凝胶治疗糖尿病足(DF)的临床疗效。方法将80例DF患者按照随机数字表法分为2组。对照组40例予纳米银抗菌凝胶创面换药治疗,治疗组40例在对照组治疗基础上加四妙勇安汤,2组均2周为1个疗程,共治疗2个疗程后统计疗效。比较2组治疗前后血液流变学指标[血浆黏度、全血黏度(200)、全血黏度(100)、全血黏度(50)、全血黏度(5)、全血黏度(1)]、外周血炎症相关因子[肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)、IL-10、C反应蛋白(CRP)]水平及跛行距离。结果治疗后,2组血浆黏度、全血黏度(200)、全血黏度(100)、全血黏度(50)、全血黏度(5)、全血黏度(1)均较本组治疗前降低(P<0.05),且治疗组均低于对照组(P<0.05)。治疗后,2组血清TNF-α、IL-6、CRP水平均较本组治疗前降低(P<0.05),且治疗组均低于对照组(P<0.05)。2组治疗后IL-10水平均较本组治疗前升高(P<0.05),且治疗组高于对照组(P<0.05)。治疗后,2组跛行距离均较本组治疗前增加(P<0.05),且治疗组高于对照组(P<0.05)。治疗组总有效率为87.5%(35/40),对照组总有效率为62.5%(25/40),治疗组总有效率高于对照组(P<0.05)。结论四妙勇安汤联合纳米银抗菌凝胶治疗DF疗效确切,其机制可能与抑制炎症和改善血液流变有关。

诃子提取物对3种致病菌的体外抑菌效果及其机制研究

为探究诃子在畜禽疫病防控中的作用及应用潜力,以大肠埃希菌、肺炎克雷伯菌和阴沟肠杆菌3种常见致病菌为对象,对比诃子和其他11种中药提取物的抑菌圈直径和最小抑菌浓度(MIC),分析诃子培养上清液的总漏出率和电导率、蛋白浓度及诃子对细菌DNA和蛋白含量的影响。结果显示:诃子比其他11种中药的抑菌效果更强,表现为抑菌圈直径更大,MIC更低。培养上清液的电导率和漏出率增加,用2倍MIC诃子药液处理8 h后,大肠埃希菌和肺炎克雷伯菌上清液蛋白浓度显著增加(P<0.05)。诃子抑制大肠埃希菌蛋白合成,使分子质量约为80 ku的蛋白缺失;对肺炎克雷伯菌和阴沟肠杆菌蛋白质合成影响不明显,对细菌DNA也没有明显的凝胶阻滞作用,但能降解DNA。以上结果表明:诃子具有较好的抑菌效果,其作用机制是通过破坏细菌细胞膜通透性,抑制细菌核酸和蛋白合成而发挥抑菌作用。