Evaluation of the Controlled Release Ability of Theophylline from Xanthan/Chondroitin Sulfate Hydrogels

Abstract

<p> <span><span style="font-family:Verdana;font-size:12px;">The xanthan/chondroitin sulfate (X/CS) hydrogels, obtained by a crosslinking technique, were evaluated </span><i><span style="font-family:Verdana;font-size:12px;">in vitro</span></i><span style="font-family:Verdana;font-size:12px;"> and </span><i><span style="font-family:Verdana;font-size:12px;">in vivo</span></i><span style="font-family:Verdana;font-size:12px;"> as matrices for theophylline release. The influence of pH of simulated physiological media on the X/CS swelling behaviour at 37°C was investigated. The hydrogels theophylline loading degree was evaluated by near infrared chemical imaging (NIR-CI) technique and confirmed also by FT-IR spectroscopy; the drug loading was about 77.5% based on PLS-DA prediction (Partial least squares</span></span><span style="font-family:Verdana;font-size:12px;">-</span><span style="font-family:Verdana;font-size:12px;">Discriminate Analysis). The release profiles of theophylline from X/CS hy</span><span style="font-family:Verdana;font-size:12px;">drogels in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) depend on CS content. The release mecha</span><span style="font-family:Verdana;font-size:12px;">nisms were controlled by the drug solubility and ionic properties of the polymers.</span><span> </span><i><span style="font-family:Verdana;font-size:12px;">In vivo</span></i><span style="font-family:Verdana;font-size:12px;"> theophylline delivery was done by oral administration. Pharmacokinetic analysis revealed sustained-release characteristics for 50/50 X/CS theo</span><span><span style="font-family:Verdana;font-size:12px;">phylline-loaded formulation compared with raw theophylline which was rapidly absorbed, distributed and eliminated. A good </span><i><span style="font-family:Verdana;font-size:12px;">in vitro-in vivo</span></i><span style="font-family:Verdana;font-size:12px;"> correlation was found.</span></span><span></span> </p

Surface characterization and drug release from porous microparticles based on methacrylic monomers and xanthan

“…For this reason, the present work is focused on the surface characterization of porous 89 microparticles based on glycidyl methacrylate and xanthan and in vitro evaluation of theophylline 90 release, an oral bronchodilator drug that is prescribed together with other drugs for patients with 91 breathing problems such as, asthma, chronic obstructive pulmonary diseases (chronic bronchitis and 92 emphysema) and other lung diseases (Oprea et al, 2013;Yuen et al, 1993). A c c e p t e d M a n u s c r i p t 5 2014).…”

A review of recent trends in polymer characterization using non-destructive vibrational spectroscopic modalities and chemical imaging

“…Infrared & Raman spectroscopy are the most widespread vibrational spectroscopic modalities in common use [7][8] [9]. When infrared radiation passes through a sample, bonds between atoms vibrate due to absorption of energy Different molecules and functional groups exhibit characteristic absorption peaks corresponding to the frequency of a vibration in a given molecule [10] [11].…”

“…However, when the homogeneity of polymeric properties throughout a sample is of interest vibrational point spectroscopy is somewhat limited [9] because the spatial variation of these properties is not measured.…”

“…Multivariate or Chemometric methods can remedy this situation, as seen in [9], as well as hardware advances such as the optimization of spectral widths of pulses, for time resolved CARS studies [8].…”

“…Hydrogels containing theophylline constitute a new class of biocompatible drug delivery systems. Oprea et al [9] investigated the use of NIR chemical imaging ( transmission converted to absorbance, 1000-2500nm range) to study the loading degree of theophylline in a Xanthum/Chondroitin sulphate(X/CS) hydrogel mix. Three hypercubes were captured: pure theophylline, X/CS (50:50 ratio) hydrogel, X/CS (50:50 ratio) hydrogel loaded with theophylline and were compared to analyse theophylline distribution and loading.…”