Bioadhesive Fluorescent Microspheres as Visible Carriers for Local Delivery of Drugs. II: Uptake of Insulin-Loaded PCEFB/PLGA Microspheres by the Gastrointestinal Tract

Li, Y.; Jiang, Hongliang; Jin, Jiayu; Zhu, K. J.

doi:10.1080/10717540490494005

Cited by 10 publications

(5 citation statements)

References 12 publications

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“…[1,2] Fluorescence microscopy is a comprehensive tool for investigating many of these aspects in drug-delivery systems or for other biomedical applications. [3,4] For instance, fluorescent objects have been used as in vivo tracers for evaluation of the uptake of nano-and microparticles in the gastrointestinal tract, [5,6] cellular internalization of polymeric micelles, [7] localization of in vivo gene transfection and for brain research. [8][9][10][11] Since the fluorescent probes were only physically incorporated into micro-or nanoparticles in many studies, the presence of the fluorescent dyes may influence the surface properties of particles, changing the intrinsic interaction of particles with particular tissues or cells.…”

Section: Introductionmentioning

confidence: 99%

Versatile Preparation of Fluorescent Particles Based on Polyphosphazenes: From Micro‐ to Nanoscale

Zhang

Qiu

Jin

et al. 2007

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A series of intrinsically fluorescent hydrophobic and amphiphilic polyphosphazenes with ethyl tryptophan (EtTrp) and poly(N-isopropylacrylamide) (PNIPAAm) or poly(ethylene glycol) (PEG) as hydrophobic and hydrophilic segments, respectively, are synthesized. Depending on polymer composition and preparation procedure, particles with diameters ranging from micro- to nanoscale can be prepared successfully, which might be used as a visible tracer, both in vitro or in vivo, in drug- or gene-delivery systems, as well as in other biomedical studies such as diagnostic medicine and brain research. Most importantly, in combination with the flexible synthesis and versatile modification of polyphosphazene, this method provides a general protocol to engineer a broad range of fluorescent particles with different properties based on diverse polymers.

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Section: Introductionmentioning

confidence: 99%

Versatile Preparation of Fluorescent Particles Based on Polyphosphazenes: From Micro‐ to Nanoscale

Zhang

Qiu

Jin

et al. 2007

Small

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“…The fate of poly (isobutylcyanoacrylate) nanocapsules carrying insulin administered to rats was monitored by fluorescence and transmission electron microscopy (TEM) and evidenced intestinal absorption through the epithelial mucosa (PintoAlphandary et al, 2003). A luminescent polymer was used as a visible tracer to monitor the oral fate of PLGA microspheres containing insulin (Li, Jang, Jin, 2004). The therapeutic effects of another peptide, octreotide, can be improved and prolonged on incorporation into PACA nanocapsules (Damge et al, 1997a).…”

Section: Introductionmentioning

confidence: 99%

Atorvastatin calcium loaded chitosan nanoparticles: in vitro evaluation and in vivo pharmacokinetic studies in rabbits

Ahmed¹,

Konwar²,

Sengupta³

2015

Braz. J. Pharm. Sci.

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In this study, we prepared atorvastatin calcium (AVST) loaded chitosan nanoparticles to improve the oral bioavailability of the drug. Nanoparticles were prepared by solvent evaporation technique and evaluated for its particle size, entrapment efficiency, zeta potential, in vitro release and surface morphology by scanning electron microscopy (SEM). In addition, the pharmacokinetics of AVST from the optimized formulation (FT5) was compared with marketed immediate release formulation (Atorva ® ) in rabbits. Particle size of prepared nanoparticles was ranged between 179.3 ± 7.12 to 256.8 ± 8.24 nm with a low polydispersity index (PI) value. Zeta potential study showed that the particles are stable with positive values between 13.03 ± 0.32 to 46.90 ± 0.49 mV. FT-IR studies confirmed the absence of incompatibility of AVST with excipient used in the formulations. In vitro release study showed that the drug release was sustained for 48 h. Results of pharmacokinetics study showed significant changes in the pharmacokinetic parameter (2.2 fold increase in AUC) of the optimized formulation as compared to marketed formulation (Atorva ® ). Thus, the developed nanoparticles evidenced the improvement of oral bioavailability of AVST in rabbit model. Uniterms:Atorvastatin calcium/oral bioavailability/experimental study. Atorvastatin calcium/in vitro release. Atorvastatin calcium/pharmacokinetics. Nanoparticles/drugs bioavailability.No presente estudo, preparamos nanopartículas de quitosana com atorvastatina cálcica (AVST) para melhorar a biodisponibilidade oral do fármaco. As nanopartículas foram preparadas pela técnica de evaporação de solvente, avaliando-se a granulometria, a eficiência de encapsulamento, o potencial zeta, a liberação in vitro e a morfologia da superfície, por meio da microscopia eletrônica de varredura (MEV). Além disso, a farmacocinética da formulação otimizada de AVST (FT5) foi comparada com a formulação comercial, de liberação imediata, comercializada (Atorva®), em coelhos. O tamanho das das nanopartículas variou na faixa de 179,3 a 256,8 ± 7,12 ± 8,24 nm, com baixo índice polidispersibilidade (PI). O estudo do potencial Zeta mostrou que as partículas são estáveis, com valores positivos entre 13,03 ± 0,32 a 46,90 ± 0,49 mV. Os estudos de FT-IR confirmaram a ausência de incompatibilidade de AVST com o excipiente utilizado nas formulações. O estudo de liberação in vitro mostrou que liberação sustentada do fármaco por 48 horas. Os resultados do estudo farmacocinético mostraram alterações significativas nos parâmetros (aumento de 2,2 vezes na ASC) da formulação otimizada em relação à comercializada (Atorva® ). Assim, o desenvolvimento de nanopartículas evidenciou a melhora da biodisponibilidade oral de AVST em coelhos.Uniterms: Atorvastatina cálcica/biodisponibilidade oral/estudo experimental. Atorvastatina cálcica/ liberação in vitro. Atorvastatina cálcica/farmacocinética. Nanopartículas/biodisponibilidade de fármacos.

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“…However, the fluorescence emitted from P(dCPS:SA) 50:50 was still strong enough to illuminate the microsphere even when the copolymer degraded in pH 7.4 PBS for one month. These inherently luminescent properties, as well as the biodegradability, render P(dCPS:SA) microspheres ideal fluorescent tracers for monitoring their cellular or tissue uptake, avoiding the need of labeling with fluorescent probes which may contaminate the surface of the studied particles 26–31…”

Section: Resultsmentioning

confidence: 99%

Novel Copolyanhydrides Combining Strong Inherent Fluorescence and a Wide Range of Biodegradability: Synthesis, Characterization and in vitro Degradation

Jiang

Chen

Zhao

et al. 2005

Macromolecular Bioscience

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In this work, a novel diacid monomer was synthesized in a very convenient scheme. The monomer is derived from naturally occurring products and emits strong fluorescence when polymerized to polyanhydride. The chemical structure of the monomer dCPS is as follows: HOC(O)ArOC(O)(CH2)2C(O)O--Ar--COOH. Copolyanhydrides composed of dCPS and sebacic acid were further prepared by melt copolycondensation, and characterized by IR, NMR, UV-Vis, DSC and fluorometry. The emission wavelength (lambda(em)) of the copolymers could be tuned by the excitation wavelength (lambda(ex)). Fluorescence intensity increased with the increase of dCPS content. The microspheres fabricated from the copolymer with dCPS content as low as 10% could be clearly visualized with fluorescence microscopy. Either blue or green images of the microspheres could be captured with an excitation of UV and visible light. The degradation rate of the copolyanhydrides decreased as the dCPS fraction increased, and the degradation duration could be modulated from several days to more than three months. In addition, it was found that the copolyanhydrides displayed surface degradation characteristics. In view of the advantages of the novel copolyanhydrides, such as easy preparation, unique inherent luminescent properties, and widely adjustable degradation rate, they might be useful for biomedical engineering.

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Bioadhesive Fluorescent Microspheres as Visible Carriers for Local Delivery of Drugs. II: Uptake of Insulin-Loaded PCEFB/PLGA Microspheres by the Gastrointestinal Tract

Cited by 10 publications

References 12 publications

Versatile Preparation of Fluorescent Particles Based on Polyphosphazenes: From Micro‐ to Nanoscale

Versatile Preparation of Fluorescent Particles Based on Polyphosphazenes: From Micro‐ to Nanoscale

Atorvastatin calcium loaded chitosan nanoparticles: in vitro evaluation and in vivo pharmacokinetic studies in rabbits

Novel Copolyanhydrides Combining Strong Inherent Fluorescence and a Wide Range of Biodegradability: Synthesis, Characterization and in vitro Degradation

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