Synthesis, Characterization, and Properties of Copolyanhydrides Based on 2-Octylsuccinic Acid and Sebacic Acid

2008 ◽  
Vol 61 (10) ◽  
pp. 762 ◽  
Author(s):  
Yousef M. Hamdan ◽  
Shitao Fu ◽  
Xiangmei Jiang ◽  
Yinhua Cheng ◽  
Kaixun Huang ◽  
...  
Keyword(s):  
Release Kinetics ◽  
Sebacic Acid ◽  
Gel Permeation Chromatography ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Scanning Calorimetry ◽  
First Order ◽  
Melt Polycondensation ◽  
Model Drug

2-Octylsuccinic acid and its copolyanhydrides with sebacic acid have been synthesized by melt polycondensation, and were characterized by Fourier transform infrared spectroscopy, 1H NMR, gel permeation chromatography, differential scanning calorimetry, and thermal gravimetric analysis. In vitro studies showed that all copolymers are degradable in phosphate buffer at 37°C. The release profiles of the hydrophilic model drug ciprofloxacin hydrochloride follow first-order release kinetics.

scholarly journals Synthesis, Characterization andIn VitroAnticancer Evaluation of Itaconic Acid Based Random Copolyester

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
J. Gowsika ◽  
R. Nanthini
Keyword(s):  
Itaconic Acid ◽  
Hydrolytic Degradation ◽  
Gel Permeation Chromatography ◽  
Xrd Analysis ◽  
Titanium Tetraisopropoxide ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
H Nmr ◽  
Melt Polycondensation

The present study deals with the synthesis and characterization of an aliphatic copolyester, poly [butylene fumarate-co-butylene itaconate] (PIFB) copolymer was obtained from itaconic acid, fumaric acid, and 1,4-butanediol using titanium tetraisopropoxide (TTiPO) through a two step process of transesterification and melt polycondensation. The synthesized aliphatic random copolyester was characterized with the help of FT-IR,1H-NMR,13C-NMR, viscosity measurements, Gel Permeation Chromatography (GPC) and X-ray diffraction (XRD) analysis. Thermal properties have been analyzed using thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). Hydrolytic degradation studies were carried out in acid and alkaline regions of various pH values. The synthesized copolymer was subjected toin vitroanticancer activity studies against human breast cancer (MCF-7) cell line.

scholarly journals Preparation, Characterization and Dissolution Behaviour of Freeze Dried Complexes of Curcumin-Gamma Cyclodextrin

2021 ◽  
pp. 17-26
Author(s):  
M. J. Ansari ◽  
K. Kohli ◽  
J. Ali
Keyword(s):  
Inclusion Complexes ◽  
Release Kinetics ◽  
In Vitro Release ◽  
Stoichiometric Ratio ◽  
Scanning Calorimetry ◽  
First Order ◽  
Rate Of Dissolution ◽  
Freeze Dried ◽  
Gamma Cyclodextrin

The aim of the current research was to develop and characterize curcumin-gamma cyclodextrin inclusion complexes in order to enhance solubility and rate of dissolution of poorly soluble curcumin. Based on the stoichiometric ratio of 1:1, the inclusion complexes of curcumin with γ-cyclodextrin were prepared by freeze drying method. The prepared dried and solidified inclusion complexes were characterized with the help of infrared spectroscopy, differential scanning calorimetry, and X-ray diffractometry. The comparative evaluation of solubility and rate of dissolution were investigated and compared with pure curcumin. Dissolution study demonstrated only 10% release from pure curcumin at 1 hour as opposed of approximately 72% release form freeze dried curcumin complexes. The freeze dried complexes exhibited almost complete release after 5 hours while only 34% release was observed from the pure curcumin during the same time period. Therefore, the freeze dried complex provided approximately 3 to 7-fold enhancement in the dissolution and release of curcumin over a period of 6 hours of dissolution testing.  The kinetics of the in vitro release behaviors of the curcumin and curcumin complexes were investigated by applying various models such as zero order, first order, Higuchi and Peppas models. The release of the curcumin was observed to follow the first order release kinetics, since the correlation coefficient (R2) for the first order was the highest in comparison to other kinetic models.

scholarly journals Enhancement of Antioxidant and Hydrophobic Properties of Alginate via Aromatic Derivatization: Preparation, Characterization, and Evaluation

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2575
Author(s):  
Smaher M. Elbayomi ◽  
Haili Wang ◽  
Tamer M. Tamer ◽  
Yezi You
Keyword(s):  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Hydroxyl Group ◽  
Hydroxyl Groups ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Benzoyl Group ◽  
Antioxidant Evaluation ◽  
Thermo Stability

The preparation of bioactive polymeric molecules requires the attention of scientists as it has a potential function in biomedical applications. In the current study, functional substitution of alginate with a benzoyl group was prepared via coupling its hydroxyl group with benzoyl chloride. Fourier transform infrared spectroscopy indicated the characteristic peaks of aromatic C=C in alginate derivative at 1431 cm−1. HNMR analysis demonstrated the aromatic protons at 7.5 ppm assigned to benzoyl groups attached to alginate hydroxyl groups. Wetting analysis showed a decrease in hydrophilicity in the new alginate derivative. Differential scanning calorimetry and thermal gravimetric analysis showed that the designed aromatic alginate derivative demonstrated higher thermo-stability than alginates. The aromatic alginate derivative displayed high anti-inflammatory properties compared to alginate. Finally, the in vitro antioxidant evaluation of the aromatic alginate derivative showed a significant increase in free radical scavenging activity compared to neat alginate against DPPH (2,2-diphenyll-picrylhydrazyl) and ABTS free radicals. The obtained results proposed that the new alginate derivative could be employed for gene and drug delivery applications.

scholarly journals Formulation and development of metformin-loaded microspheres using Khaya senegalensis (Meliaceae) gum as co-polymer

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Chukwuebuka H. Ozoude ◽  
Chukwuemeka P. Azubuike ◽  
Modupe O. Ologunagba ◽  
Sejoro S. Tonuewa ◽  
Cecilia I. Igwilo
Keyword(s):  
Controlled Release ◽  
Sodium Alginate ◽  
Release Kinetics ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Entrapment Efficiency ◽  
Metformin Hydrochloride ◽  
Scanning Calorimetry ◽  
Khaya Senegalensis

Abstract Background Khaya gum is a bark exudate from Khaya senegalensis (Maliaecae) that has drug carrier potential. This study aimed to formulate and comparatively evaluate metformin-loaded microspheres using blends of khaya gum and sodium alginate. Khaya gum was extracted and subjected to preformulation studies using established protocols while three formulations (FA; FB and FC) of metformin (1% w/v)-loaded microspheres were prepared by the ionic gelation method using 5% zinc chloride solution as the cross-linker. The formulations contained 2% w/v blends of khaya gum and sodium alginate in the ratios of 2:3, 9:11, and 1:1, respectively. The microspheres were evaluated by scanning electron microscopy, Fourier transform-infrared spectroscopy, differential scanning calorimetry, entrapment efficiency, swelling index, and in vitro release studies. Results Yield of 28.48%, pH of 4.00 ± 0.05, moisture content (14.59% ± 0.50), and fair flow properties (Carr’s index 23.68 ± 1.91 and Hausner’s ratio 1.31 ± 0.03) of the khaya gum were obtained. FTIR analyses showed no significant interaction between pure metformin hydrochloride with excipients. Discrete spherical microspheres with sizes ranging from 1200 to 1420 μm were obtained. Drug entrapment efficiency of the microspheres ranged from 65.6 to 81.5%. The release of the drug from microspheres was sustained for the 9 h of the study as the cumulative release was 62% (FA), 73% (FB), and 80% (FC). The release kinetics followed Korsmeyer-Peppas model with super case-II transport mechanism. Conclusion Blends of Khaya senegalensis gum and sodium alginate are promising polymer combination for the preparation of controlled-release formulations. The blend of the khaya gum and sodium alginate produced microspheres with controlled release properties. However, the formulation containing 2:3 ratio of khaya gum and sodium alginate respectively produced microspheres with comparable controlled release profiles to the commercial brand metformin tablet.

Synthesis, characterization and corrosion protection properties of polyN-(p-bromophenyl)-2-methacrylamide-co-glycidyl methacrylate on low nickel stainless steel

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Sakvai Mohammed Safiullah ◽  
Deivasigamani Thirumoolan ◽  
Kottur Anver Basha ◽  
K. Mani Govindaraju ◽  
Dhanraj Gopi ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Corrosion Protection ◽  
Glycidyl Methacrylate ◽  
Electrochemical Impedance ◽  
Thermo Gravimetric Analysis ◽  
Gel Permeation Chromatography ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Protection Efficiency ◽  
Ft Ir

Abstract The synthesis of copolymers from different feed ratios of N-(p-bromophenyl)-2- methacrylamide (PBPMA) and glycidyl methacrylate (GMA) was achieved by using free radical solution polymerization technique and characterized using FT-IR, 1H and 13C NMR spectroscopy. The thermal stability of the synthesized copolymers was studied using thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC). The molecular weight of the copolymer is determined by gel permeation chromatography (GPC). The corrosion performances of low nickel stainless steel specimens dip coated with different composition of copolymers were investigated in 0.5 M H2SO4 using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) techniques. The polarization and impedance measurements showed different corrosion protection efficiency with change in composition of the copolymers. It was found that the corrosion protection properties are owing to the barrier effect of the polymer layer covered on the low nickel stainless steel surfaces. However, it is observed that the mole ratio of PBPMA and GMA plays a major role in the protective nature of the copolymer.

Synthesis, Characterization and Application of Multi-Generations Hyperbranched Polyurethane Based on Isophorone Diisocyanate

2012 ◽  
Vol 554-556 ◽  
pp. 126-129 ◽  
Author(s):  
Shun Yin ◽  
Ning Sun ◽  
Chun Yun Feng ◽  
Zhi Mou Wu ◽  
Zhao Hua Xu ◽  
...  
Keyword(s):  
Differential Scanning Calorimetry ◽  
Raw Materials ◽  
Degradation Mechanism ◽  
Resonance Spectroscopy ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Isophorone Diisocyanate ◽  
Scanning Calorimetry ◽  
Degradation Temperature ◽  
Hyperbranched Polyurethane

A series of different generation hyperbranched polyurethane(HBPU) was synthesized based on the raw materials of isophorone diisocyanate(IPDI) and diethanolamine(DEOA). Their structure, thermal degradation mechanism and glass transition temperature(Tg) were characterized by fourier transform infrared spectroscopy(FTIR), nuclear magnetic resonance spectroscopy(NMR), thermal gravimetric analysis(TGA) and differential scanning calorimetry(DSC). The results showed that: the yield of each generation HBPU was up to 90%, different generation HBPU had almost the same initial degradation temperature(about at 200°C) and they all had two decomposition platforms; with the increase of generation, Tg increased from 107.2°C to 132.1°C. The gloss and hardness of the HBPU coatings were significantly improved.

scholarly journals Development of a reservoir type prolonged release system with felodipine via simplex methodology

2015 ◽  
Vol 89 (1) ◽  
pp. 128-136
Author(s):  
Rareș Iuliu Iovanov ◽  
Ioan Tomuță ◽  
Sorin Emilian Leucuța
Keyword(s):  
Simplex Method ◽  
Release Kinetics ◽  
Prolonged Release ◽  
Lauryl Sulfate ◽  
Pore Former ◽  
Release System ◽  
Reservoir Type ◽  
Model Drug ◽  
Kinetics Of

Background and aims. Felodipine is a dihydropyridine calcium antagonist that presents good characteristics to be formulated as prolonged release preparations. The aim of the study was the formulation and in vitro characterization of a reservoir type prolonged release system with felodipine, over a 12 hours period using the Simplex method.Methods. The first step of the Simplex method was to study the influence of the granules coating method on the felodipine release. Furthermore the influence of the coating polymer type, the percent of the coating polymer and the percent of pore forming agent in the coating on the felodipine release were studied. Afterwards these two steps of the experimental design the percent of Surelease applied on the felodipine loaded granules and the percent of pore former in the polymeric coating formulation variables were studied. The in vitro dissolution of model drug was performed in phosphate buffer solution (pH 6.5) with 1% sodium lauryl sulfate. The released drug quantification was done using an HPLC method. The release kinetics of felodipine from the final granules was assessed using different mathematical models.Results. A 12 hours release was achieved using granules with the size between 315 – 500 µm coated with 45% Surelease with different pore former ratios in the coating via the top-spray method.Conclusion. We have prepared prolonged release coated granules with felodipine using a fluid bed system based on the Simplex method. The API from the studied final formulations was released over a 12 hours period and the release kinetics of the model drug substance from the optimized preparations fitted best the Higuchi and Peppas kinetic models. 

scholarly journals In Vitro Release Kinetics Study of Different Brands of Esomeprazole Sustained Release Tablets Available in Bangladesh

1970 ◽  
Vol 2 (1) ◽  
pp. 27-31 ◽  
Author(s):  
Abul Kalam Lutful Kabir ◽  
Tasbira Jesmeen ◽  
Md Mesbah Uddin Talukder ◽  
Abu Taher Md Rajib ◽  
DM Mizanur Rahman
Keyword(s):  
Drug Release ◽  
Sustained Release ◽  
Release Kinetics ◽  
Matrix Tablets ◽  
In Vitro Dissolution ◽  
National Brand ◽  
First Order ◽  
Time Period ◽  
Esomeprazole Magnesium

Commercially available four national and four international brands of esomeprazole magnesium sustained release matrix tablets were studied in simulated gastric medium (pH 1.2) for 2 hours and simulated intestinal medium (pH 6.8) for 8 hours time period using USP reference dissolution apparatus. All the national and international brands complied with the USP in-vitro dissolution specifications for drug release in simulated gastric medium. However, one of the national brands (Code: MP-1) and one of the international brands (MP-7) failed to fulfill the official requirement of 80% drug release within 8th hour in simulated intestinal medium. Drug release of that national and international brand were 70.49% and 67.05% respectively within the specified time period, however one national brand (Code: MP-4) released 103.46 % drug within 8th hour in intestinal medium. Drug release profiles were analyzed for zero order, first order and Higuchi equation to reveal the release kinetics perspective of esomeprazole magnesium sustained release matrix tablets. It was found that zero order release kinetics was the predominant release mechanism than first order and Higuchi release kinetics for those brands (Code: MP-2, MP-3, MP-4, MP-5, MP-6 and MP-8) which complied with the USP in vitro dissolution specification for drug releases. On the other hand, first order release kinetics was predominant for one national and also one international non compliant brands (Code: MP-1 and MP-6). Key Words: In vitro dissolution; Sustained release; Market preparations; Kinetic analysis; Esomeprazole; National brand; International brand. DOI: 10.3329/sjps.v2i1.5812Stamford Journal of Pharmaceutical Sciences Vol.2(1) 2009: 27-31

scholarly journals Development and In-Vitro Evaluation of pH Responsive Polymeric Nano Hydrogel Carrier System for Gastro-Protective Delivery of Naproxen Sodium

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Rai Muhammad Sarfraz ◽  
Muhammad Rouf Akram ◽  
Muhammad Rizwan Ali ◽  
Asif Mahmood ◽  
Muhammad Usman Khan ◽  
...  
Keyword(s):  
Drug Release ◽  
Naproxen Sodium ◽  
Research Work ◽  
Entrapment Efficiency ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Swelling Behaviour ◽  
X Ray

Current research work was carried out for gastro-protective delivery of naproxen sodium. Polyethylene glycol-g-poly (methacrylic acid) nanogels was developed through free radical polymerization technique. Formulation was characterized for swelling behaviour, entrapment efficiency, Fourier transform infrared (FTIR) spectroscopy, Differential scanning calorimetry (DSC), and Thermal Gravimetric Analysis (TGA), Powder X-ray diffraction (PXRD), Zeta size distribution, and Zeta potential measurements, and in-vitro drug release. pH dependent swelling was observed with maximum drug release at higher pH. PXRD studies confirmed the conversion of loaded drug from crystalline to amorphous form while Zeta size measurement showed size reduction. On the basis of these results it was concluded that prepared nanogels proved an effective tool for gastro-protective delivery of naproxen sodium.

The Use of a Small, Low-Cost FT-IR Spectrometer as a Mobile Analyzer for Fluid Streams

1985 ◽  
Vol 39 (6) ◽  
pp. 909-915 ◽  
Author(s):  
D. A. C. Compton ◽  
M. Markelov ◽  
M. L. Mittleman ◽  
J. G. Grasselli
Keyword(s):  
Mobile Applications ◽  
Low Cost ◽  
Gel Permeation Chromatography ◽  
Infrared Analysis ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Evolved Gases ◽  
Gel Permeation ◽  
Ft Ir ◽  
Being Moved

Infrared analysis is well established as a prime method for identification of unknown samples. However, the instruments needed for recording a complete infrared spectrum have not lent themselves to mobile applications because of their inherent mechanical fragility. The design of a commercial low-cost FT-IR instrument described herein makes it particularly useful as a mobile analyzer since it is optically rugged and has sufficient on-board computer power to record high-quality spectra after being moved between locations. At the same time, it is physically small enough to be mounted on a standard lab cart along with the necessary accessories. We illustrate the use of this mobile, low-cost FT-IR for analyzing the evolved gases from Thermal Gravimetric Analysis, small pilot reactors, and the liquid eluant from Gel Permeation Chromatography.

Sign in / Sign up

Export Citation Format

Share Document