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Drug Nanoparticle Formulation Using Ascorbic Acid Derivatives  [PDF]
Kunikazu Moribe,Waree Limwikrant,Kenjirou Higashi,Keiji Yamamoto
Journal of Drug Delivery , 2011, DOI: 10.1155/2011/138929
Abstract: Drug nanoparticle formulation using ascorbic acid derivatives and its therapeutic uses have recently been introduced. Hydrophilic ascorbic acid derivatives such as ascorbyl glycoside have been used not only as antioxidants but also as food and pharmaceutical excipients. In addition to drug solubilization, drug nanoparticle formation was observed using ascorbyl glycoside. Hydrophobic ascorbic acid derivatives such as ascorbyl mono- and di-n-alkyl fatty acid derivatives are used either as drugs or carrier components. Ascorbyl n-alkyl fatty acid derivatives have been formulated as antioxidants or anticancer drugs for nanoparticle formulations such as micelles, microemulsions, and liposomes. ASC-P vesicles called aspasomes are submicron-sized particles that can encapsulate hydrophilic drugs. Several transdermal and injectable formulations of ascorbyl n-alkyl fatty acid derivatives were used, including ascorbyl palmitate.
Formulation and in Vivo Evaluation for Anti-Aging Effects of an Emulsion Containing Basil Extract Using non- Invasive Biophysical Techniques
A. Rasul,N. Akhtar
DARU : Journal of Pharmaceutical Sciences , 2011,
Abstract: Background and the purpose of study: Skin aging is a complex process induced by constant exposure to ultraviolet (UV) irradiation and damages human skin. UV generates reactive oxygen species leading to collagen deficiency and eventually skin wrinkling. Basil contains a number of phenolics and favonoids which possess antioxidant properties. The aim of this study was to formulate and investigate the antiaging potential of a cream containing Basil extract. Methods: A single blinded study was conducted using non-invasive methods. Formulation containing 3% of the concentrated extract of Basil was developed by entrapping in the inner aqueous phase of w/o emulsion and base contained no extract. Both creams were stored at different storage conditions of 8°C, 25°C, 40°C and 40°C+ 75% relative humidity to predict their stabilities. The formulation and base were evaluated for their effects on various skin parameters i.e., moisture and trans epidermal water loss (TEWL), volume, energy and surface evaluation of the living skin (SELS). Results: Significant effects (p≤0.05) were observed for both creams in the case of TEWL. The base showed insignificant (p≤0.05) while formulation showed significant effects on skin moisture. Volume, SELS SEr (skin roughness), SEsc (skin scaliness), SEsm (skin smoothness), SEw (skin wrinkles) parameter showed significant decline while texture parameter of ‘Energy' showed significant increase. Conclusion: The results statistically indicated that the active formulation containg extract of Basil exert antiaging effects when applied topically.
ASSAY OF ASCORBIC ACID BY RP-HPLC IN SAMPLES CONTAINING ALSO CITRIC ACID  [PDF]
V. Ostafe,C. Brumaru,Gabriela Papoe,Ioana Lupsa
Annals of West University of Timi?oara : Series of Biology , 1999,
Abstract: The ascorbic acid is widely used as antioxidant in food products. As this substance is a very unstable substance, its concentration needs an accurate monitorization. A RP-HPLC method was used for identification and quantification of ascorbic acid in mixtures used in sausage industry. Reliable results are obtained even the samples contain high quantities of citric acid. The regression coefficient of standard curve is 0.999.
Formulation and Evaluation of Ascorbic acid Tablets by Direct Compression using Microcrystalline Starch as a Direct Compression Excipient
YE Apeji, AR Oyi, H Musa
International Journal of Health Research , 2011,
Abstract: PURPOSE: To evaluate the tableting properties of microcrystalline starch (MCS) used as a direct compression excipient in the formulation of ascorbic acid tablets and to compare with the properties of tablets produced using microcrystalline cellulose (MCC). METHODS: MCS was obtained by partial hydrolysis of cassava (Manihot esculenta Crantz) starch using the enzyme, á-amylase. The hydrolysis was allowed to proceed for 5 hr under controlled temperature and pH (56 °C, 6). The derived MCS was recovered by filtration after precipitation with ethanol (95%v/v). Powder properties were investigated and tablets of ascorbic acid were formulated using MCS and MCC as direct compression excipients. RESULTS: Mechanical properties of tablets formulated with MCS were comparable to those of MCC. Tablets formulated with MCS disintegrated within 15 min and gave a 100% release of ascorbic acid within 30 min compared to MCC which disintegrated after 60 min. CONCLUSION: MCS can be incorporated as a direct compression excipient in the formulation of heat and/or moisture sensitive drugs by direct compression.
Formulation and Evaluation of Ascorbic acid Tablets by Direct Compression using Microcrystalline Starch as a Direct Compression Excipient
YE Apeji, AR Oyi, H Musa
International Journal of Health Research , 2012,
Abstract: PURPOSE: To evaluate the tableting properties of microcrystalline starch (MCS) used as a direct compression excipient in the formulation of ascorbic acid tablets and to compare with the properties of tablets produced using microcrystalline cellulose (MCC). METHODS: MCS was obtained by partial hydrolysis of cassava (Manihot esculenta Crantz) starch using the enzyme, á-amylase. The hydrolysis was allowed to proceed for 5 hr under controlled temperature and pH (56 °C, 6). The derived MCS was recovered by filtration after precipitation with ethanol (95%v/v). Powder properties were investigated and tablets of ascorbic acid were formulated using MCS and MCC as direct compression excipients. RESULTS: Mechanical properties of tablets formulated with MCS were comparable to those of MCC. Tablets formulated with MCS disintegrated within 15 min and gave a 100% release of ascorbic acid within 30 min compared to MCC which disintegrated after 60 min. CONCLUSION: MCS can be incorporated as a direct compression excipient in the formulation of heat and/or moisture sensitive drugs by direct compression.
Preparation and Characterization of Poly(D,L-Lactide-co-Glycolide) Nanoparticles Containing Ascorbic Acid
Magdalena M. Stevanovi ,Branka Jordovi ,Dragan P. Uskokovi
Journal of Biomedicine and Biotechnology , 2007, DOI: 10.1155/2007/84965
Abstract: This paper is covering new, simplistic method of obtaining the system for controlled delivery of the ascorbic acid. Copolymer poly (D,L-lactide-co-glycolide) (DLPLG) nanoparticles are produced using physical method with solvent/nonsolvent systems where obtained solutions were centrifuged. The encapsulation of the ascorbic acid in the polymer matrix is performed by homogenization of water and organic phases. Particles of the DLPLG with the different content of ascorbic acid have different morphological characteristics, that is, variable degree of uniformity, agglomeration, sizes, and spherical shaping. Mean sizes of nanoparticles, which contain DLPLG/ascorbic acid in the ratio 85/150%, were between 130 to 200 nm depending on which stereological parameters are considered (maximal diameters Dmax, feret X, or feret Y). By introducing up to 15% of ascorbic acid, the spherical shape, size, and uniformity of DLPLG particles are preserved. The samples were characterized by infrared spectroscopy, scanning electron microscopy, stereological analysis, and ultraviolet spectroscopy.
Antitumoral activity of L-ascorbic acid-poly-D,L-(lactide-co-glycolide) nanoparticles containing violacein
Dorival Martins, Lucas Frungillo, Maristela C Anazzetti, et al
International Journal of Nanomedicine , 2010, DOI: http://dx.doi.org/10.2147/IJN.S7833
Abstract: ntitumoral activity of L-ascorbic acid-poly-D,L-(lactide-co-glycolide) nanoparticles containing violacein Original Research (5080) Total Article Views Authors: Dorival Martins, Lucas Frungillo, Maristela C Anazzetti, et al Published Date January 2010 Volume 2010:5 Pages 77 - 85 DOI: http://dx.doi.org/10.2147/IJN.S7833 Dorival Martins1, Lucas Frungillo2, Maristela C Anazzetti2, Patrícia S Melo3, Nelson Durán1 1Institute of Chemistry, Biological Chemistry Laboratory, Universidade Estadual de Campinas-UNICAMP, C.P. 6154, CE P 13083-970, Campinas, SP, Brazil; 2Institute of Biology, Cell Cultures and Biopharmaceutical Laboratory, Universidade Estadual de Campinas, UNICAMP, Campinas, SP, Brazil; 3Campinas Integrated Metropolitan Faculties-METROCAMP, Campinas, SP, Brazil Abstract: It has been demonstrated that tumoral cells have a higher uptake of ascorbic acid compared to normal cells. This differential characteristic can be used as a way to improve the specificity of antitumoral compounds if combined with polymeric drug delivery systems. The aim of this study was to prepare, characterize and evaluate the antitumoral activity of poly-D,L-(lactide-co-glycolide) 50:50 loading the antitumoral compound violacein and capped with L-ascorbic acid. Nanoparticles were prepared using the nanoprecipitation method and morphologically characterized by scanning electron microscopy (SEM). The average diameter and Zeta potential were determined by photon correlation spectroscopy method (PCS), and assays were carried out to determine the content of ascorbic acid and in vitro drug release kinetics. The antitumoral activity of this system was also evaluated against HL-60 cells by tetrazolium reduction assay. Nanoparticles with size distribution between 300–400 nm and strong negative outer surface (-40 mV) were obtained by this method. Analysis of ascorbic acid content showed that this compound was mainly localized on the external surface of nanoparticles. Violacein loading efficiency was determined as 32% ± 1% and this drug was gradually released from nanoparticles at different rates depending on the composition of the release media. In addition, this system was observed to be 2 × more efficient as an antitumoral compared with free violacein.
Antitumoral activity of L-ascorbic acid-poly-D,L-(lactide-co-glycolide) nanoparticles containing violacein  [cached]
Dorival Martins,Lucas Frungillo,Maristela C Anazzetti,et al
International Journal of Nanomedicine , 2010,
Abstract: Dorival Martins1, Lucas Frungillo2, Maristela C Anazzetti2, Patrícia S Melo3, Nelson Durán11Institute of Chemistry, Biological Chemistry Laboratory, Universidade Estadual de Campinas-UNICAMP, C.P. 6154, CE P 13083-970, Campinas, SP, Brazil; 2Institute of Biology, Cell Cultures and Biopharmaceutical Laboratory, Universidade Estadual de Campinas, UNICAMP, Campinas, SP, Brazil; 3Campinas Integrated Metropolitan Faculties-METROCAMP, Campinas, SP, BrazilAbstract: It has been demonstrated that tumoral cells have a higher uptake of ascorbic acid compared to normal cells. This differential characteristic can be used as a way to improve the specificity of antitumoral compounds if combined with polymeric drug delivery systems. The aim of this study was to prepare, characterize and evaluate the antitumoral activity of poly-D,L-(lactide-co-glycolide) 50:50 loading the antitumoral compound violacein and capped with L-ascorbic acid. Nanoparticles were prepared using the nanoprecipitation method and morphologically characterized by scanning electron microscopy (SEM). The average diameter and Zeta potential were determined by photon correlation spectroscopy method (PCS), and assays were carried out to determine the content of ascorbic acid and in vitro drug release kinetics. The antitumoral activity of this system was also evaluated against HL-60 cells by tetrazolium reduction assay. Nanoparticles with size distribution between 300–400 nm and strong negative outer surface (-40 mV) were obtained by this method. Analysis of ascorbic acid content showed that this compound was mainly localized on the external surface of nanoparticles. Violacein loading efficiency was determined as 32% ± 1% and this drug was gradually released from nanoparticles at different rates depending on the composition of the release media. In addition, this system was observed to be 2 × more efficient as an antitumoral compared with free violacein.Keywords: violacein, ascorbic acid, nanoparticles, PLGA
Analytical Electron Microscopy for Characterization of Fluid or Semi-Solid Multiphase Systems Containing Nanoparticulate Material  [PDF]
Victoria Klang,Claudia Valenta,Nadejda B. Matsko
Pharmaceutics , 2013, DOI: 10.3390/pharmaceutics5010115
Abstract: The analysis of nanomaterials in pharmaceutical or cosmetic preparations is an important aspect both in formulation development and quality control of marketed products. Despite the increased popularity of nanoparticulate compounds especially in dermal preparations such as emulsions, methods and protocols of analysis for the characterization of such systems are scarce. This work combines an original sample preparation procedure along with different methods of analytical electron microscopy for the comprehensive analysis of fluid or semi-solid dermal preparations containing nanoparticulate material. Energy-filtered transmission electron microscopy, energy-dispersive X-ray spectroscopy, electron energy loss spectroscopy and high resolution imaging were performed on model emulsions and a marketed product to reveal different structural aspects of both the emulsion bulk phase and incorporated nanosized material. An innovative analytical approach for the determination of the physical stability of the emulsion under investigation is presented. Advantages and limitations of the employed analytical imaging techniques are highlighted.
Amperometric biosensor for ascorbic acid
Tomita, I. N.;Manzoli, A.;Fertonani, F. L.;Yamanaka, H.;
Eclética Química , 2005, DOI: 10.1590/S0100-46702005000200005
Abstract: a l-ascorbic acid biosensor based on ascorbate oxidase has been developed. the enzyme was extracted from the mesocarp of cucumber (cucumis sativus) by using 0.05 mol l-1 phosphate buffer, ph 5.8 containing 0.5 mol l-1 nacl. after the dialysis versus phosphate buffer 0.05 mol l-1 ph 5.8, the enzyme was immobilized onto nylon net through glutaraldehyde covalent bond. the membrane was coupled to an o2 electrode and the yielding reaction monitored by oxygen depletion at -600 mv using flow injection analysis optimized to 0.1 mol l-1 phosphate buffer ph 5.8, as the carrier solution and flow-rate of 0.5 ml min-1. the ascorbic acid calibration curve was linear from 1.2x10-4 to 1.0x10-3 mol l-1. the evaluation of biosensor lifetime leads to 500 injections. commercial pharmaceutical samples were analyzed with the proposed method and the results were compared with those obtained by high-performance liquid chromatography (hplc).
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