Green synthesis of multifunctional carbon dots for anti-cancer and anti-fungal applications

Carbon dots(CDs)have become popular nanomaterials in biomedical and agricultural fields.Herein we synthesized multifunctional CDs which showed anti-cancer and anti-fungal activities.The low cytotoxicity,stable fluorescence and high photothermal conversion efficiency enable the CDs with imagingguided photothermal therapy.The CDs also exhibited intrinsic anti-fungal activity even at a low concentration,i.e.,40 mg·L^(-1) of CDs induced 20%mortality in cucumber downy mildew.Moreover,the largeπ-conjugated nanostructure and the richness of amino and hydroxyl groups make them a powerful delivery platform for flumorph(a fungicide)with a high loading efficiency of 47.18%.Meanwhile,the heat converted from the light can accelerate the release of flumorph from CDs,and thus efficiently kill fungus.

A"donor–acceptor"structured semiconductor polymer for near infrared fluorescence imaging guided photodynamic therapy

Near infrared(NIR)fluorescence imaging guided photodynamic therapy(PDT)is a technique which has been developed in many clinical trials due to its advantage of real-time optical monitoring,specific spatiotemporal selectivity,and minimal invasiveness.For this,photosensitizers with NIR fluorescence emission and high^(1)O_(2)generation quantum yield are highly desirable.Herein,we designed and synthesized a"donor-acceptor"(D-A)structured semiconductor polymer(SP),which was then wrapped with an amphiphilic compound(Pluronic■F127)to prepare water-soluble nanoparticles(F-SP NPs).The obtained F-SP NPs exhibit good water solubility,excellent particle size stability,strong absorbance at deep red region,and strong NIR fluorescent emission characteristics.The maximal mass extinction coe±cient and fluorescence quantum yield of these F-SPs were calculated to be 21.7 L/(g·cm)and 6.5%,respectively.Moreover,the^(1)O_(2)quantum yield of 89%for F-SP NPs has been achieved under 635 nm laser irradiation,which is higher than Methylene Blue,Ce6,and PpIX.The outstanding properties of these F-SP NPs originate from their unique D-A molecular characteristic.This work should help guide the design of novel semiconductor polymer for NIR fluorescent imaging guided PDT applications.

D-A-D-structured boron-dipyrromethene with aggregation-induced enhanced phototherapeutic efficiency for near-infrared fluorescent and photoacoustic imaging-guided synergistic photodynamic and photothermal cancer therapy

Clinical phototheranostic agents suffer from low absorption in near-infrared(NIR)region,decreasing singlet oxygen quantum yield(^(1)O_(2)QY)caused by aggregation in water,and low photothermal conversion efficiency(PCE),all of which are factors weakening their phototheranostic efficacy.Herein,we designed and synthesized a donor-acceptor-donor(D-A-D)structured boron-dipyrromethene derivative(B-2TPA)which exhibited NIR absorption and fluorescence.After being encapsulated in amphiphilic distearoyl phosphoethanolamine polyethyleneglycol 2000(DSPE-PEG-2000),the water-soluble B-2TPA nanoparticles(NPs)had increasing^(1)O_(2)QY(6.7%)due to the intermolecular aggregation-induced decrease in the energy gap between singlet and triplet excited states.Moreover,the quenched fluorescence and stable twisted intramolecular charge transfer in aggregates further increased the PCE of B-2TPA NPs to 60.1%.In vitro and in vivo studies confirmed that B-2TPA NPs could be used in NIR fluorescence and photoacoustic imagingguided synergistic photodynamic and photothermal therapy in tumor treatment.

Cisplatin-appended BODIPY for near infraredⅡfluorescent and photoacoustic imaging-guided synergistic phototherapy and chemotherapy of cancer

Combining phototherapy and chemotherapy has been considered a promising modality for cancer therapy due to their synergistic effect.Herein,we developed three D-π-A-structured boron dipyrromethenes(BODIPYs)(named as B-B,B-C,and B-C-Pt).Due to their enlargedπ-conjugated structure and high intramolecular charge transfer effect,the synthesized BODIPYs had photothermal conversion capability,and their absorption and fluorescence spectra were red-shifted.The cisplatin-appended BODIPY(B-C-Pt)exhibited good singlet oxygen(^1O_(2))generation ability and near infrared(NIR)absorption and fluorescence(λ_(Abs)=748 nm,λ_(Em)=947 nm).After being encapsulated by distearoyl phosphoethanolamine polyethyleneglycol 2000(DSPE-PEG-2000),which could inhibit the H-aggregation of B-C-Pt,the absorption and fluorescence of the obtained B-C-Pt nanoparticles(NPs)were red-shifted to 762 and 985 nm,respectively.The^1O_(2)quantum yield and photothermal conversion efficiency of the B-C-Pt NPs were 4.0%and 40.6%,respectively.Moreover,B-C-Pt NPs had chemotherapeutic efficacy due to the presence of cisplatin.In vitro and in vivo studies further demonstrated that B-C-Pt NPs had synergistic therapeutic efficacy.Together,B-C-Pt NPs could be employed in NIRⅡfluorescent and photoacoustic imaging-guided synergistic phototherapy and chemotherapy for cancer treatment.

All-in-one phototheranostics based on BTP-4F-DMO nanoparticles for NIR-II fluorescence/photoacoustic dual-mode imaging and combinational therapy

Various phototheranostics have recently been developed for phototherapy.Through proper molecular design,the photochemical and photophysical properties of these phototheranostics can be promoted.Herein,an acceptor-donor-acceptor(A-D-A)-structured dye,BTP-4F-DMO,was synthesized and prepared into water-soluble nanoparticles(NPs).The obtained BTP-4F-DMO NPs had strong absorption from650 nm to 850 nm and a fluorescence emission peak at~900 nm that tailed to~1100 nm.The NPs showed a superhigh photothermal conversion efficiency of 90.5%±5%and could simultaneously generate·OH and^(1)O_(2)with a^(1)O_(2)generation quantum yield of 4.6%under 808 nm laser irradiation.Due to these advanced properties,BTP-4F-DMO NPs can switch the role of autophagy from pro-survival to prodeath,thereby further promoting cancer cell death.These features make BTP-4F-DMO NPs a promising multifunctional phototheranostic agent for NIR-II fluorescence/photoacoustic dual-mode imaging-guided synergetic photodynamic/photothermal therapy.In general,this work provides a strategy for expanding the biomedical applications of organic A-D-A-structured phototheranostics.

自组装槲皮素-Fe^(3+)纳米颗粒用于协同近红外光触发的低温光热/谷胱甘肽激活化学动力学治疗

光热疗法(PTT)与化学动力疗法(CDT)相结合是一种有效的癌症治疗策略.然而,高温诱导的热休克反应和低Fenton反应效率限制了其临床应用.在这里,我们提出了自组装槲皮素-Fe^(3+)纳米颗粒(Qu-Fe NPs)用于协同近红外(NIR)光触发低温PTT (LTPTT)和谷胱甘肽(GSH)激活CDT.Qu-Fe NPs具有较宽的吸收范围,可延伸至近红外区域,光热转换能力良好.这些NPs在进入癌细胞后,释放出来的Qu可下调HSP70的表达,以实现LTPTT.此外,Qu-Fe NPs可以消耗癌细胞中的GSH,增加癌细胞对活性氧的敏感性.同时,Fe^(3+)可以被还原为Fe^(2+),与内源性H_(2)O_(2)反应生成羟基自由基,实现CDT.PTT产生的热量可以进一步加速CDT中的Fenton反应,从而导致LTPTT与CDT之间的协同效应.实验结果表明,Qu-Fe NPs能有效抑制肿瘤生长.这项工作提出了一种新的方法来实现LTPTT/CDT的联合治疗.

受体-供体-受体结构光疗试剂用于近红外二区荧光成像和光声成像引导的光动力和光热联合治疗

多模态成像引导的光动力和光热治疗在癌症治疗上具有明显的优势.同时具有近红外光(NIR)吸收、高活性氧(ROS)产率和高光热转换效率的物质是非常理想的光疗试剂.本文设计合成了一种具有“受体-供体-受体”(A-D-A)结构的分子IDCIC.随后通过在IDCIC表面包裹DSPE-PEG2000-NH2得到了水溶性纳米颗粒IDCIC NPs.IDCIC NPs具有近红外吸收,峰值位于760 nm;同时还具有近红外二区荧光发射,峰值在1000 nm左右,荧光量子产率为1.2%,使得IDCIC NPs具有良好的光声成像和NIR-Ⅱ荧光成像能力.此外,IDCIC NPs在808 nm激光器照射下可以同时产生单线态氧(量子产率为9.1%)、羟基自由基(·OH)和热量(光热转换效率为78.9%).基于以上这些特性,IDCIC NPs可以用于多模态成像引导的光动力/光热联合癌症治疗.

Optically tunable fluorescent carbon nanoparticles and their application in fluorometric sensing of copper ions

A series of carb on nano particles(CNPs)with emissi on wavele ngth ranging from 483 to 525 nm were prepared by hydrothermal treatme nt of poly-3-thiopheneacetic acid(PTA)and NaOH.The emission wavelength and surface oxidation degree of CNPs were shown to be controllable by simply adjusti ng NaOH concentration.These CNPs prese nted obvious fluoresce nee spectral response toward copper ions(Cu^2+)through static quenching caused synergistically by electron transfer and inner filter effect.The O-and S-containing groups on the surface of CNPs were dem on strated to be resp on sible for their outsta nding sensing performa nee.Based on that,a CN Ps-based ratiometric fluoresce nt probe for Cu^2+with a high fluoresce nee quenching rate constant of 1.4×10^5 L/mol and a short resp onse time(10 s)was developed.Their practical applications in detecting Cu^2+in pond water and living cells were also dem on strated.

Recent advances in nanomaterials for sonodynamic therapy

Sonodynamic therapy(SDT),as a novel non-invasive strategy for eliminating tumor,has the advantages of deeper tissue penetration,fewer side effects,and better patient compliance,compared with photodynamic therapy(PDT).In SDT,ultrasound was used to activate sonosensitizer to produce cytotoxic reactive oxygen species(ROS),induce the collapse of vacuoles in solution,and bring about irreversible damage to cancer cells.In recent years,much effort has been devoted to developing highly efficient sonosensitizers which can efficiently generate ROS.However,the traditional organic sonosensitizers,such as porphyrins,hypericin,and curcumins,suffer from complex synthesis,poor water solubility,and low tumor targeting efficacy which limit the benefits of SDT.In contrast,inorganic sonosensitizers show good in vivo stability,controllable physicochemical properties,ease of achieving multifunctionality,and high tumor targeting,which greatly expanded their application in SDT.In this review,we systematically summarize the nanomaterials which act as the carrier of molecular sonosensitizers,and directly produce ROS under ultrasound.Moreover,the prospects of inorganic nanomaterials for SDT application are also discussed.

Carbon dot-based fluorescent and colorimetric sensor for sensitive and selective visual detection of benzoyl peroxide

Benzoyl peroxide(BPO) has been added in wheat flour because of its bleaching effect. However, the abnormal used BPO has caused increasing concern due to its strong oxidization capability which may have adverse effects on living organisms. Herein, we present a carbon dot(CD)-based fluorescent and colorimetric probe for visually, sensitively and selectively sensing BPO. The addition of BPO could quench the red fluorescence of CDs peaked at 622 and 677 nm, and decrease the absorbance at 613 nm, while increase the absorbance at 450 nm, resulting in a fluorescence turn-off and colorimetric spectral response.Moreover, the CDs had short response time of 10 min and high sensitivity towards BPO with a low limit of detection of 28 nmol/L. The applicability of the CDs in detecting BPO in wheat, noodle and starch samples was further demonstrated, and good recovery results were obtained.