Incorporation of Silicon Carbide and Diamond-Like Carbon as Adhesion Promoters Improves In Vitro and In Vivo Stability of Thin-Film Glassy Carbon Electrocorticography Arrays

For neural applications, materials able to interface with the brain without harming it while recording high-fidelity signals over long-term implants are still sought after. Glassy Carbon (GC) and Poly (3,4-ethylenedioxythiophene)-poly (styrenesulfonate) (PEDOT-PSS) have proved to be promising materials for neural interfaces as they show – compared to conventional metal electrodes - higher conductivity, better electrochemical stability, very good mechanical properties and therefore seem to be very promising for in vivo applications. We present here, for the first time, a direct comparison between GC and PEDOT-PSS microelectrodes in terms of biocompatibility, electrical and electrochemical properties as well as in vivo recording capabilities, using electrocorticography microelectrode arrays located on flexible polyimide substrate. The GC microelectrodes were fabricated using a traditional negative lithography processes followed by pyrolysis. PEDOT-PSS was selectively electrodeposited on the desired electrodes. Electrochemical performance of the two materials was evaluated through electrochemical impedance spectroscopy and cyclic voltammetry. Biocompatibility was assessed through in-vitro studies evaluating cultured cells viability. The in vivo performance of the GC and PEDOT-PSS electrodes was directly compared by simultaneously recording neuronal activity during somatosensory stimulation in Long-Evans rats. We found that both GC and PEDOT-PSS electrodes outperform metals in terms of electrochemical performance and allow to obtain excellent recordings of somatosensory evoked potentials from the rat brain surface. Furthermore, we found that both GC and PEDOT-PSS substrates are highly biocompatible, confirming that they are safe for neural interface applications.

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In vitro and Short-term in vivo Characteristics of a Kel-F Thin Film Modified Glucose Sensor

Analytical Sciences ◽

10.2116/analsci.19.1481 ◽

2003 ◽

Vol 19 (11) ◽

pp. 1481-1486 ◽

Cited By ~ 2

Author(s):

Sun Kil KANG ◽

Ran-A JEONG ◽

Sejin PARK ◽

Taek Dong CHUNG ◽

Sunmin PARK ◽

...

Keyword(s):

Thin Film ◽

Glucose Sensor ◽

Short Term

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In vitro and in vivo testing of a novel, hyperelastic thin film nitinol flow diversion stent

Journal of Biomedical Materials Research Part B Applied Biomaterials ◽

10.1002/jbm.b.32504 ◽

2011 ◽

Vol 100B (3) ◽

pp. 718-725 ◽

Cited By ~ 9

Author(s):

C. P. Kealey ◽

Y. J. Chun ◽

F. E. Viñuela ◽

K. P. Mohanchandra ◽

G. P. Carman ◽

...

Keyword(s):

Thin Film ◽

Flow Diversion ◽

In Vivo Testing

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In Vitro and In Vivo Performance of Dry Powder Inhalation Formulations: Comparison of Particles Prepared by Thin Film Freezing and Micronization

AAPS PharmSciTech ◽

10.1208/s12249-014-0126-7 ◽

2014 ◽

Vol 15 (4) ◽

pp. 981-993 ◽

Cited By ~ 19

Author(s):

Yi-Bo Wang ◽

Alan B. Watts ◽

Jay I. Peters ◽

Sha Liu ◽

Ayesha Batra ◽

...

Keyword(s):

Thin Film ◽

Dry Powder Inhalation ◽

Dry Powder ◽

Thin Film Freezing

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FORMULATION AND EVALUATION OF CURCUMIN LOADED LIPOSOME AND ITS BIO-ENHANCEMENT

Journal of Drug Delivery and Therapeutics ◽

10.22270/jddt.v9i4-a.3505 ◽

2019 ◽

Vol 9 (4-A) ◽

pp. 425-437

Author(s):

Khushboo Verma ◽

Jhakeshwar Prasad ◽

Suman Saha ◽

Surabhi Sahu

Keyword(s):

Thin Film ◽

Particle Size ◽

Drug Release ◽

Zeta Potential ◽

High Performance ◽

Encapsulation Efficiency ◽

Mean Particle Size ◽

Liposome Formulation

The aim of this work was to develop and evaluate curcumin loaded liposome and its bio- enhancement. Curcumin was selected as a natural drug for liposome formulation. Curcumin show variety of biological activity but it also shows poor bioavailability due to low aqueous solubility (1 µg/ml), poor absorption and rapid metabolism so that piperine was selected as bio enhancer to improve curcumin bioavailability. Soy lecithin and cholesterol were used to prepared curcumin and curcumin-piperine loaded liposome at different ratio by thin film hydration method because of easy to perform, and high encapsulation rates of lipid. The all liposome formulations (F1-F5) were evaluated by mean particle size, polydispersity index, zeta potential, encapsulation efficiency and drug release. Bioavailability was also determined on rat. Blood samples were collected at specific intervals, and plasma was separated by ultracentrifugation. Plasma was analyzed by high-performance liquid chromatography at 425 nm taking acetonitrile: water (75:25 v/v) acidified with 2% acetic acid as a mobile phase at a flow rate of 0.5 ml/min using C18 column. The mean particle size was found in the range between 800-1100 that indicate liposome are large unilamellar vesical types. By zeta potential study its conform that the all formulation was stable. The encapsulation efficiency of all liposome formulation are varied between 59-67%. In vitro drug release was analyse in 7.4 pH phosphate buffer, the maximum %CDR observed at the 12 hrs., and formulation are follow sustained release thus they reduce metabolism, good absorption rate which improve bioavailability of drug. From in-vivo study, it is clear that curcumin-piperine liposomal formulation, increases Cmax, area under the curve, and mean residence time significantly as compared to pure curcumin and pure curcumin liposome. Keywords: liposome; Curcumin; Piperine, Thin film hydration method; Bioavailability

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Synthesis of TPGS/Curcumin Nanoparticles by Thin-Film Hydration and Evaluation of Their Anti-Colon Cancer Efficacy In Vitro and In Vivo

Frontiers in Pharmacology ◽

10.3389/fphar.2019.00769 ◽

2019 ◽

Vol 10 ◽

Cited By ~ 9

Author(s):

Hong Li ◽

Liping Yan ◽

Edith K.Y. Tang ◽

Zhen Zhang ◽

Wei Chen ◽

...

Keyword(s):

Thin Film ◽

Colon Cancer ◽

Curcumin Nanoparticles

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Single-Crystal Silicon Carbide: A Biocompatible and Hemocompatible Semiconductor for Advanced Biomedical Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.679-680.824 ◽

2011 ◽

Vol 679-680 ◽

pp. 824-830 ◽

Cited By ~ 24

Author(s):

Stephen E. Saddow ◽

Christopher L. Frewin ◽

Camilla Coletti ◽

N. Schettini ◽

E. Weeber ◽

...

Keyword(s):

Silicon Carbide ◽

Cell Lines ◽

Platelet Adhesion ◽

Crystalline Silicon ◽

Fluorescent Microscopy ◽

Wild Type Mouse ◽

System Response ◽

Tissue Cell

Crystalline silicon carbide (SiC) and silicon (Si) biocompatibility was evaluated in vitro by directly culturing three skin and connective tissue cell lines, two immortalized neural cell lines, and platelet-rich plasma (PRP) on these semiconducting substrates. The in vivo biocompatibility was then evaluated via implantation of 3C-SiC and Si shanks into a C57/BL6 wild type mouse. The in vivo results, while preliminary, were outstanding with Si being almost completely enveloped with activated microglia and astrocytes, indicating a severe immune system response, while the 3C-SiC film was virtually untouched. The in vitro experiments were performed specifically for the three adopted SiC polytypes, namely 3C-, 4H- and 6H-SiC, and the results were compared to those obtained for Si crystals. Cell proliferation and adhesion quality were studied using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays and fluorescent microscopy. The neural cells were studied via atomic force microscopy (AFM) which was used to quantify filopodia and lamellipodia extensions on the surface of the tested materials. Fluorescent microscopy was used to assess platelet adhesion to the semiconductor surfaces where significantly lower values of platelet adhesion to 3C-SiC was observed compared to Si. The reported results show good indicators that SiC is indeed a more biocompatible substrate than Si. While there were some differences among the degree of biocompatibility of the various SiC polytypes tested, SiC appears to be a highly biocompatible material in vitro that is also somewhat hemocompatible. This extremely intriguing result appears to put SiC into a unique class of materials that is both bio- and hemo-compatible and is, to the best of our knowledge, the only semiconductor with this property.

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Preparation of Prolonged-Circulating Galangin-Loaded Liposomes and Evaluation of Antitumor Efficacy In Vitro and Pharmacokinetics In Vivo

Journal of Nanomaterials ◽

10.1155/2019/7236895 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Hui Yao ◽

Hao Lu ◽

Jun Zhang ◽

Xuemei Xue ◽

Chao Yin ◽

...

Keyword(s):

Thin Film ◽

Drug Carrier ◽

Entrapment Efficiency ◽

Pharmacokinetic Parameters ◽

Pharmacological Effects ◽

Pegylated Liposomes ◽

The Mean ◽

Antibacterial And Antifungal

Galangin has been reported to have many pharmacological effects including being anti-inflammatory, antibacterial, and antifungal and a suppressor of vitiligo, Alzheimer’s disease, and cancer. The purpose of this research was to characterize and determine the efficacy of the antitumor activity and pharmacokinetics of galangin-loaded PEGylated liposomes compared with free galangin. Galangin-loaded liposomes and galangin-loaded PEGylated liposomes were prepared using thin-film dispersion prior to ultrasonication. The mean particle size of the galangin-loaded PEGylated liposomes was approximately 120 nm, the polydispersity index was 0.212, the zeta potential was -2.24 mV, and the entrapment efficiency was 76.31%. The release of galangin from galangin-loaded PEG-modified liposomes was slowest as gauged by dynamic dialysis in vitro. In the apoptosis experiment, galangin-loaded PEG-modified liposomes demonstrated cytotoxicity to hepatoma cells by apoptosis that was greater than the two other forms of drug carrier. In vivo experiments demonstrated that the half-life of galangin in PEG-modified liposomes was 4 hours in the plasma of rats, significantly longer than that of free galangin. The experimental results suggest that the PEG modification of liposomes effectively increases the solubility of galangin and alters its pharmacokinetic parameters, such that it may be effective in the treatment of liver cancer.

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