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1.
Biomater Sci ; 10(2): 376-380, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-34928270

RESUMO

Electrodynamic therapy (EDT) has recently emerged as an alternative approach for tumor therapy via the generation of ROS by platinum (Pt) nanoparticles under electric field. An interesting phenomenon observed during EDT is that the increased on-site concentration of chloride ions is highly beneficial for ROS generation and inhibition efficacy. Here, in this study, nanoclusters (KCC), consisting of potassium chloride (KCl) nanocrystals and amorphous calcium carbonate (CaCO3), were synthesized and integrated with platinum nanoparticles (KCCP). In this system, KCC can dissolve and release calcium and chloride ions within tumor cells. The intracellular chloride ions considerably facilitated ROS generation by Pt nanoparticles under an electric field. More importantly, the excessive calcium ions and ROS formed a cycle of mutual promotion and self-amplification in cells, leading to agitated tumor inhibition, both in vitro and in vivo.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Carbonato de Cálcio , Humanos , Neoplasias/tratamento farmacológico , Platina , Cloreto de Potássio
2.
J Nanobiotechnology ; 19(1): 358, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736483

RESUMO

Sonodynamic therapy (SDT), presenting spatial and temporal control of ROS generation triggered by ultrasound field, has attracted considerable attention in tumor treatment. However, its therapeutic efficacy is severely hindered by the intrinsic hypoxia of solid tumor and the lack of smart design in material band structure. Here in study, fine α-Fe2O3 nanoparticles armored with Pt nanocrystals (α-Fe2O3@Pt) was investigated as an alternative SDT agent with ingenious bandgap and structural design. The Schottky barrier, due to its unique heterostructure, suppresses the recombination of sono-induced electrons and holes, enabling superior ROS generation. More importantly, the composite nanoparticles may effectively trigger a reoxygenation phenomenon to supply sufficient content of oxygen, favoring the ROS induction under the hypoxic condition and its extra role played for ultrasound imaging. In consequence, α-Fe2O3@Pt appears to enable effective tumor inhibition with imaging guidance, both in vitro and in vivo. This study has therefore demonstrated a highly potential platform for ultrasound-driven tumor theranostic, which may spark a series of further explorations in therapeutic systems with more rational material design.


Assuntos
Antineoplásicos , Nanopartículas de Magnetita , Platina , Nanomedicina Teranóstica/métodos , Terapia por Ultrassom/métodos , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacocinética , Feminino , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Platina/química , Platina/toxicidade , Ultrassonografia
3.
Bull Math Biol ; 83(11): 116, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643801

RESUMO

In this paper, a two-strain model with coinfection that links immunological and epidemiological dynamics across scales is formulated. On the with-in host scale, the two strains eliminate each other with the strain having the larger immunological reproduction number persisting. However, on the population scale coinfection is a common occurrence. Individuals infected with strain one can become coinfected with strain two and similarly for individuals originally infected with strain two. The immunological reproduction numbers [Formula: see text], the epidemiological reproduction numbers [Formula: see text] and invasion reproduction numbers [Formula: see text] are computed. Besides the disease-free equilibrium, there are strain one and strain two dominance equilibria. The disease-free equilibrium is locally asymptotically stable when the epidemiological reproduction numbers [Formula: see text] are smaller than one. In addition, each strain dominance equilibrium is locally asymptotically stable if the corresponding epidemiological reproduction number is larger than one and the invasion reproduction number of the other strain is smaller than one. The coexistence equilibrium exists when all the reproduction numbers are greater than one. Simulations suggest that when both invasion reproduction numbers are smaller than one, bistability occurs with one of the strains persisting or the other, depending on initial conditions.


Assuntos
Coinfecção , Coinfecção/epidemiologia , Humanos , Conceitos Matemáticos , Modelos Biológicos
4.
J Nanobiotechnology ; 19(1): 313, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34641854

RESUMO

Nanoparticles, presenting catalytic activity to induce intracellular oxidative species, have been extensively explored for tumor treatment, but suffer daunting challenges in the limited intracellular H2O2 and thus suppressed therapeutic efficacy. Here in this study, a type of composite nanoparticles, consisting CaO2 core and Co-ferrocene shell, is designed and synthesized for combinational tumor treatment. The findings indicate that CaO2 core can be hydrolyzed to produce large amounts of H2O2 and calcium ions at the acidic tumor sites. Meanwhile, Co-ferrocene shell acts as an excellent Fenton catalyst, inducing considerable ROS generation following its reaction with H2O2. Excessive cellular oxidative stress triggers agitated calcium accumulation in addition to the calcium ions released from the particles. The combined effect of intracellular ROS and calcium overload causes significant tumor inhibition both in vitro and in vivo.


Assuntos
Cálcio/química , Peróxido de Hidrogênio , Nanopartículas/química , Animais , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos dos fármacos
5.
Biomater Sci ; 8(14): 3844-3855, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32555791

RESUMO

Nanoparticles presenting promoted catalytic activity, oxygen induction and loading capability are in high demand for effective synergistic tumor therapy. Herein, ferric-tannic acid complex nanocapsules with fine hollow microstructure (HFe-TA) are synthesized and loaded with a photosensitizer (indocyanine green, ICG) for synergistic tumor therapy. In acidic environment, ICG@HFe-TA decomposes and releases Fe3+ ions, TA and ICG molecules. Fe3+, with low catalytic activity, is effectively converted into highly catalytic Fe2+ by the reductant TA, enabling promoted efficacy of ˙OH induction. More importantly, the ROS (1O2) induction by ICG is significantly enhanced under 808 nm laser irradiation due to the O2 byproduct of Fe3+/Fe2+ conversion. In consequence, the ICG@HFe-TA nanoparticles exhibit considerable in vitro and in vivo tumor inhibition owing to the combined effect of ˙OH and 1O2 induced intracellularly. This study has therefore demonstrated a potential platform enabling combined photodynamic and chemodynamic therapy with high efficacy.


Assuntos
Nanocápsulas , Neoplasias , Fotoquimioterapia , Humanos , Nanocápsulas/uso terapêutico , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio , Taninos
6.
Colloids Surf B Biointerfaces ; 192: 111005, 2020 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-32315920

RESUMO

Localized drug delivery systems (LDDSs), in the forms of fibers or hydrogel, have emerged as an alternative approach for effective cancer treatment, but suffer challenges in the limited efficacy originated from sole therapeutic functionality. Herein, a multifunctional LDDS, showing feasibility for minimally-invasive implantation, was designed and synthesized for on-site chemo-photothermal synergistic therapy. In this system, polydopamine (PDA) nanoparticles, loaded with doxorubicin (DOX), were assembled at the surface of electrospun PCL-gelatin (PG) fibers (PG@PDA-DOX). The composite PG@PDA-DOX nanofibers could effectively transform NIR light into heat and present excellent photostability. In addition, low pH and NIR irradiation enabled remarkably accelerated DOX release. The in vitro study of PG@PDA-DOX fibers showed effective anti-cancer effect with irradiation of 808 nm NIR by inducing cell apoptosis and suppressing cell proliferation. The in vivo study, by implanting PG@PDA-DOX nanofibers in the patient derived xenograft (PDX) model via minimally-invasive surgery, presented that the composite fibers can effectively inhabit tumor growth by the combined chemo-photothermal effect without clear systematic side-effects. This study has therefore demonstrated a minimally-invasive platform, in a fibrous mesh form, with both high therapeutic efficacy and considerable potential in clinical translation for liver cancer treatment.

7.
J Mater Chem B ; 8(17): 3929-3938, 2020 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-32232281

RESUMO

Developing drug delivery platforms that can modulate a tumor microenvironment and deliver multiple therapeutics to targeted tumors is critical for efficient cancer treatment. Achieving these platforms still remains a great challenge. Herein, biodegradable nanocapsules based on MnFe hydroxides (H-MnFe(OH)x) have been developed as a new type of cargo delivery with high loading capacity and catalytic activity, enabling synergetic therapy with promoted efficacy by relieving hypoxia in tumor tissues. As a proof of concept, a photosensitizer (indocyanine green, ICG) and a chemotherapeutic drug (doxorubicin, DOX) are co-loaded in nanocapsules and selectively released upon degradation of the nanocapsules in the acidic tumor microenvironment, and are promoted by near infrared irradiation. Meanwhile, Mn2+/Fe3+ ions released from the degradation of nanocapsules catalyze the conversion of H2O2 in a tumor microenvironment into oxygen, which modulates tumor hypoxia and dramatically boosts multimodal therapies. Remarkable synergistic anticancer outcomes have been demonstrated both in vitro and in vivo, paving the way towards future multifunctional therapeutic platforms.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Verde de Indocianina/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Animais , Antibióticos Antineoplásicos/síntese química , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/síntese química , Doxorrubicina/química , Feminino , Humanos , Hidróxidos/química , Hidróxidos/farmacologia , Verde de Indocianina/química , Ferro/química , Ferro/farmacologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/patologia , Manganês/química , Manganês/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanocápsulas/química , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Terapia Fototérmica , Porosidade , Propriedades de Superfície , Microambiente Tumoral/efeitos dos fármacos
8.
Small ; : e1801183, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29952070

RESUMO

Localized cancer treatment is one of the most effective strategies in clinical destruction of solid tumors at early stages as it can minimize the side effects of cancer therapeutics. Electrospun nanofibers have been demonstrated as a promising implantable platform in localized cancer treatment, enabling the on-site delivery of therapeutic components and minimizing side effects to normal tissues. This Review discusses the recent cutting-edge research with regard to electrospun nanofibers used for various therapeutic approaches, including gene therapy, chemotherapy, photodynamic therapy, thermal therapy, and combination therapy, in enhancing localized cancer treatment. Furthermore, it extensively analyzes the current challenges and potential breakthroughs in utilizing this novel platform for clinical transition in localized cancer treatment.

9.
Chem Commun (Camb) ; 54(49): 6324-6327, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29862401

RESUMO

We have fabricated a flexible membrane, consisting of SiO2 nanofibres armoured with upconversion nanoparticles, exhibiting intense photoluminescence. These assemblies were subsequently grafted with molecular beacons to produce a biosensor suitable for the detection of specific microRNA and with applications in early cancer detection and point-of-care diagnosis.


Assuntos
Substâncias Luminescentes/química , Nanopartículas Metálicas/química , MicroRNAs/análise , Nanofibras/química , Dióxido de Silício/química , Técnicas Biossensoriais/métodos , Érbio/química , Limite de Detecção , Luminescência , MicroRNAs/genética , Hibridização de Ácido Nucleico , Itérbio/química , Ítrio/química
10.
J Biomed Nanotechnol ; 14(4): 698-706, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31352943

RESUMO

Clinical treatment for cancer comprises surgical removal and chemo/radio-therapy. In general, surgical intervention causes large defects while chemo/radio-therapy brings drug resistance and long-term suffering to patients. Major challenges remain in developing a therapeutic platform for simultaneous cancer treatment and tissue regeneration. In this study, a bifunctional scaffold based on gold nanorods-conjugated bioactive glass (BG@GNR) nanofibers was investigated for this purpose. Owing to gold nanoparticles anchored at the surface of nanofibers, the composite scaffold exhibits excellent photothermal effect. Under 808 nm near-infrared (NIR) irradiation for 5 minutes, the temperature of scaffold reaches ∼42.5 °C which induced more than 89.5% cancer cell death. Meanwhile, the scaffold can effectively promote the proliferation of epithelial cells by 270% after 72 h incubation, confirming its expected bioactivity. The findings suggested that the BG@GNR scaffold holds a promise for localized photothermal therapy and tissue regeneration, which is specifically inspiring in treating tumor-induced defects.


Assuntos
Nanopartículas Metálicas , Nanotubos , Ouro , Humanos , Fototerapia , Regeneração
11.
J Mater Chem B ; 5(36): 7504-7511, 2017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-29255606

RESUMO

Great efforts have been devoted to effective delivery of therapeutics into cells for cancer therapy. The exploration of nanoparticle based drug delivery systems (DDSs) faces daunting challenges in low efficacy of intracellular delivery. Herein, a localized drug delivery device consisting of photoluminescent mesoporous silica nanoparticles (PLMSNs) and photothermal fibrous matrix was investigated. Specifically, PLMSNs modified with a pH-sensitive polydopamine (PDA) 'gatekeeper' served as a doxorubicin (DOX) carrier and could release DOX once the PLMSNs were up-taken by the cancer cells. The PLMSNs were electrostatically assembled on the surface of electrospun biodegradable poly(ε-caprolactone)/gelatin fibrous mesh incorporated with photothermal carbon nanoparticles (CNPs), leading to an implantable patch used as localized delivery platform. Comparing to free particulate DDSs, this implantable composite patch device was found to significantly enable superior cell up-taking effect and consequently enhance in-vitro therapeutic efficacy against tumor cells. Namely, under near infrared irradiation, the photothermal effect of CNPs in the implantable patch weakens the electrostatic interaction between the PLMSNs and poly(ε-caprolactone)/gelatin/CNP fibrous mesh, resulting in the controlled release of the PLMSNs and subsequent internalization into the tumor cells for more effective cancer cell killing. This implantable therapeutic device may therefore inspire another way of developing localized cancer therapy.

12.
J Mater Chem B ; 5(34): 7133-7139, 2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32263904

RESUMO

MicroRNAs (miRNAs) play a key role in regulating gene expression but can be associated with abnormalities linked to carcinogenesis and tumor progression. Hence there is increasing interest in developing methods to detect these non-coding RNA molecules in the human circulation system. Here, a novel FRET miRNA-195 targeting biosensor, based on silica nanofibers incorporated with rare earth-doped calcium fluoride particles (CaF2:Yb,Ho@SiO2) and gold nanoparticles (AuNPs), is reported. The formation of a sandwich structure, as a result of co-hybridization of the target miRNA which is captured by oligonucleotides conjugated at the surface of CaF2:Yb,Ho@SiO2 fibers and AuNPs, brings the nanofibers and AuNPs in close proximity and triggers the FRET effect. The intensity ratio of green to red emission, I541/I650, was found to decrease linearly upon increasing the concentration of the target miRNA and this can be utilized as a standard curve for quantitative determination of miRNA concentration. This assay offers a simple and convenient method for miRNA quantification, with the potential for rapid and early clinical diagnosis of diseases such as breast cancer.

13.
J Mater Chem B ; 5(26): 5128-5136, 2017 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32264098

RESUMO

Photodynamic therapy (PDT) and photothermal therapy (PTT) have been explored widely for application in cancer treatment. In this work, we describe the synthesis of CaTiO3:Yb,Er (CTO) nanofibers co-conjugated with Rose Bengal (RB) and gold nanorods (AuNRs), which offer the potential for combined upconversion photoluminescence (UCPL) and enhanced, synergistic PDT and PTT. Based on this delivery platform, RB and AuNRs served as the PDT and PTT agents, respectively. RB and AuNRs have strong and well-matched absorption with the green and red emissions of UCPL CTO nanofibers respectively, hence a single 980 nm continuous wave laser with deep tissue penetration can be employed to allow PDT and PTT to occur simultaneously. The nanocomposite can effectively convert the near-infrared (NIR) radiation from the laser into a combination of targeted hyperthermia and generation of reactive oxygen species (ROS). In comparison with PDT or PTT alone, the combined PDT/PTT treatment showed significantly enhanced suppression of the viability of Hep G2 cells in vitro, demonstrating its potential for use in oncology.

14.
Chemistry ; 23(10): 2423-2431, 2017 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-27943465

RESUMO

Light-responsive and photoluminescent (PL) drug-delivery platforms have sparked fascinating advancements in personalized tumor chemotherapy due to their unique characteristics in biological imaging and manipulated release kinetics. Herein, implantable Yb3+ and Ho3+ co-doped strontium titanate (SrTiO3 :Yb,Ho) nanofibers were synthesized and decorated on the surface with polyacrylic acid (PAA) molecules. The preliminary in vitro assay confirmed that this implantable fibrous mesh presented sound cytocompatibility. The PAA surface decoration improved the loading capacity of an anticancer drug (doxorubicin (DOX)) and effectively prevented a daunting burst release in a neutral aqueous environment. Owing to the electrostatic bond between PAA and DOX molecules, low-pH microenvironments and NIR (λ=808 nm) irradiation both induced significantly accelerated DOX release and consequently enhanced the local cancer-cell-killing effect. Additionally, the ratio of green-to-red emission (I545 /I655 ) from the SrTiO3 :Yb,Ho-PAA fibers responded effectively to the DOX release progress and dosage due to a fluorescence resonance energy transfer (FRET) effect. This unique characteristic enabled optical monitoring of the delivery progress in a timely manner. These SrTiO3 :Yb,Ho-PAA nanofibers, with precise dual-triggering and optical monitoring of DOX release, are expected to serve as a new implantable drug delivery platform for personalized chemotherapy in the future.


Assuntos
Portadores de Fármacos/química , Nanofibras/química , Óxidos/química , Estrôncio/química , Titânio/química , Resinas Acrílicas/química , Antineoplásicos/química , Antineoplásicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/toxicidade , Liberação Controlada de Fármacos , Transferência Ressonante de Energia de Fluorescência , Células Hep G2 , Hólmio/química , Humanos , Concentração de Íons de Hidrogênio , Raios Infravermelhos , Microscopia de Fluorescência , Eletricidade Estática , Itérbio/química
15.
Langmuir ; 32(35): 9083-90, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27557281

RESUMO

Implantable localized drug delivery systems (LDDSs) with intelligent functionalities have emerged as a powerful chemotherapeutic platform in curing cancer. Developing LDDSs with rationally controlled drug release and real-time monitoring functionalities holds promise for personalized therapeutic protocols but suffers daunting challenges. To overcome such challenges, a series of porous Yb(3+)/Er(3+) codoped CaTiO3 (CTO:Yb,Er) nanofibers, with specifically designed surface functionalization, were synthesized for doxorubicin (DOX) delivery. The content of DOX released could be optically monitored by increase in the intensity ratio of green to red emission (I550/I660) of upconversion photoluminescent nanofibers under 980 nm near-infrared (NIR) excitation owing to the fluorescence resonance energy transfer (FRET) effect between DOX molecules and the nanofibers. More importantly, the 808 nm NIR irradiation enabled markedly accelerated DOX release, confirming representative NIR-triggered drug release properties. In consequence, such CTO:Yb,Er nanofibers presented significantly enhanced in vitro anticancer efficacy under NIR irradiation. This study has thus inspired another promising fibrous LDDS platform with NIR-triggered and optics-monitored DOX releasing for personalized tumor chemotherapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Preparações de Ação Retardada/efeitos da radiação , Doxorrubicina/farmacologia , Portadores de Fármacos , Hepatócitos/efeitos dos fármacos , Nanofibras/química , Antibióticos Antineoplásicos/química , Compostos de Cálcio/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/metabolismo , Doxorrubicina/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Transferência Ressonante de Energia de Fluorescência , Hepatócitos/patologia , Humanos , Raios Infravermelhos , Cinética , Nanofibras/ultraestrutura , Óxidos/química , Titânio/química
16.
ACS Biomater Sci Eng ; 2(4): 652-661, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33465865

RESUMO

Implantable localized drug delivery systems (LDDSs) have been intensively investigated for cancer therapy. However, the anticancer agent release behavior as well as the local therapeutic process in the complex physiological environment remains a dark zone and consequently hinders their clinical applications. Herein, a series of Er3+-doped electrospun strontium titanate (SrTiO3, STO) nanofibers with refined microstructural characteristics were exploited as a localized carrier for doxorubicin (DOX) delivery due to its light-responsive functionalities as well as expected biocompatibility. The highest DOX loading capacity and sustained releasing kinetics were obtained from the nanofibers with the highest surface area and lowest pore dimensions. Consequently, such nanofibers presented stronger in vitro anticancer efficacy to Hep G2 cells compared to that of other samples. More importantly, the amount of drug released was monitored by the ratio of green-to-red emission (I550/I660) due to the fluorescence resonance energy transfer (FRET) effect built between DOX molecules and upconversion photoluminescent nanofibers. The selective quenching effect of green emission due to DOX molecules was gradually weakened with drug releasing progress, whereas the intensity of red emission barely changed, resulting in an increased I550/I660 ratio. Such color evolution can be feasibly visualized by the naked eye. Monitoring with a spectral intensity ratio eliminates the disturbance of uncertainties in the complex physiological environment compared to just referring to the emission intensity. Such dual-color luminescent STO:Er nanofibers, designed based on the FRET mechanism, are therefore considered to be a promising new LDDS platform with ratiometric-monitored DOX release functionalities for future localized tumor therapeutic strategies.

17.
ACS Appl Mater Interfaces ; 7(45): 25514-21, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26544158

RESUMO

The design of multifunctional localized drug delivery systems (LDDSs) has been endeavored in the past decades worldwide. The matrix material of LDDSs is known as a crucial factor for the success of its transformation from the laboratory to clinical practices. Herein, a biocompatible ceramic, strontium titanate (SrTiO3, STO), was utilized as the matrix. A variety of fine Er doped SrTiO3 (STO:Er) nanofibers were fabricated via electrospinning. After the surface functionalization with amino groups, the drug loading capacity of STO:Er nanofibers is dramatically increased. The nanofibers present a rather sustained drug releasing behavior in the media with pH of 7.4, and the release kinetics is significantly accelerated with the decreased pH value from 7.4 to 4.7. Furthermore, the intensity of the spectrum emitted from the STO:Er nanofibers corresponds well with the drug releasing progress under the excitation of near-infrared spectrum (∼980 nm). Fast drug release behavior (in an acid environment) induces a rapid intensity enhancing effect of photoluminescence emission and vice versa. The main mechanism is attributed to the quenching effect induced by the C-Hx groups of IBU molecules with vibration frequencies from 2850 to 3000 cm(-1). Such new STO:Er nanofibers with pH-triggered and optically monitored drug delivery functionalities have therefore been considered as another new localized drug delivery platform for modern tumor diagnosis and therapy.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Érbio/química , Nanofibras/química , Óxidos/química , Estrôncio/química , Titânio/química , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Ibuprofeno/farmacologia , Nanofibras/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
18.
Curr Pharm Des ; 21(22): 3239-47, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26027562

RESUMO

Electrohydrodynamic atomization (EHDA) enabling platform technologies have gathered significant momentum over the last two decades. Utilisation of the underpinning jetting process in tandem with desired materials (including polymers, ceramics, metals and even naturally occurring compounds such as peptides, DNA and cells) provides the basis for novel engineered therapies. Through EHDA processes, the generation of a variety of nano-meter and micro-meter scaled structures with control on surface and encapsulation features is attainable in a single step. While a host of adaptable EHDA techniques have evolved (e.g. printing and template patterning), there are two main processes that continue to dominate: electrospraying (ESy) and electrospinning (ESp). Although ESp has drawn considerable researcher interest for nanofibre applications, ESy is an important and timely process for nano- and micro-particle fabrication. Thus, an appropriate evaluation of ESy is vital. This short review focuses on key developments in the ESy field in relation to nanotechnologies with potential healthcare applications using metals, polymers and ceramics. An insight into the process of particle formation (during EHDA spraying or ESy), process parameters and materials specifications, is provided. Emerging biomedical and other healthcare research through nanotechnologies are highlighted.


Assuntos
Nanotecnologia , Humanos , Metais/química , Nanomedicina/métodos , Nanopartículas/química , Nanotecnologia/métodos , Polímeros/química , Propriedades de Superfície
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