Combination Of Hydrophilic Polymers Research Articles

Formulation and In-Vitro evaluation of Nortriptyline Hydrochloride mucoadhesive buccal films

This contemporaneous research was aimed to formulate buccal mucoadhesive DDS to enhance bioavailability and avoid pre systemic metabolism. The mucoadhesive film was fabricated by solvent casting method with base polymer chitosan and a combination of hydrophilic polymer like PVP or Gelatin. The films were then evaluated. All the formulations were found to have optimum strength to withstand folding endurance. The films' consistent size, thickness, and weight variation were discovered. The drug content uniformity of films was exceptionally well. Given that the film's surface pH falls between 6.6 and 6.7, buccal administration is appropriate for it. The pH near to the neutral region decreases the chances of mucosal irritation. The invitro adhesion ability of the formulations were affected by the composition of chitosan and PVP or Gelatin. The lower and higher concentration of chitosan was not sufficient for invitro adhesion of films. The formulation having chitosan and hydrophilic polymers in the ratio 1:1.5 showed strong invitro adhesion. The invitro bioadhesion time of the formulations containing chitosan and gelatin or PVP was less due to poor ionization of gelatin. On increasing the concentration of hydrophilic polymers, the invitro bioadhesion time increased. The highest concentration of the polymers decreased the adhesion time. The formulation NF5 with chitosan and gelatin within the proportion of 1:1.5 exhibited drug release of 98.1% at 6 hours. The sole purpose of this work is to adhere the buccal film with the mucosa, hence formulation NF5 was selected as best formulation. Thus, current investigation's goal to develop a buccal mucoadhesive drug delivery was fulfilled.
 Keywords: Buccal film, Nortriptyline HCl, depression, in vitro studies, mucoadhesive

Development and evaluation of floating tablet of metoprolol succinate for increased bioavailability

<p>The present study is based on development and evaluation of gastroretentive floating tablets of metoprolol succinate by direct compression method, to increase the oral bioavailability of MS. For this, we used a combination of two different hydrophilic polymers that is polyethylene oxide PEO N-80 (X1) and hydroxy ethylcellulose HEC (X2) as independent variables and studied its effect on drug release (as dependent variable) at 20h for MS. A 3<sup>2</sup> factorial design was used for optimization purpose.</p><p>The DSC result shows no interaction between two polymers and the drug (MS). Further, in vitro drug release studies have shown a sustained drug release for more than 20h in upper gastrointestinal region (stomach). In vivo study using rabbits have shown increased AUC<sub>0-24 </sub>(bioavailability) of prepared optimized F6 formulation as compared to the marketed sustain release tablet of MS. Stability study shows no comparable differences on physical parameters and the drug release after 3 months of accelerated stability testing. Hence, we can conclude that a floating tablet containing combination of hydrophilic polymers can be used for gastric retention for more than 20hr which will increase the oral bioavailability of MS.</p>

Design of Extended Release Matrix Tablet of Tramadol hydrochloride Using Combination of Hydrophobic and Hydrophilic Polymer

The aim of design of oral extended drug delivery system is to achieve a prolonged therapeutic effect by continuously releasing medicament over an extended period of time after administration of a single dose. An attempt was made to formulate Tramadol Extended Release (ER) matrix tablet using combination of hydrophobic and hydrophilic polymer consisting of ethyl cellulose, HPMC K15M, carbopol, and xanthan gum. The polymeric concentration of hydrophobic and hydrophilic polymer was optimized and was found that drug to polymeric ratio (hydrophobic and hydrophilic) of 1:0.75:0.75 was appropriate for the formulation of Tramadol ER tablet. The concentration of hydrophobic polymer was kept constant were as the combination of hydrophilic polymer was attempted and combined to hydrophobic polymer to retard the drug release for 24-hour from the matrix tablet. A total of nine formulations (F1-F9) of Tramadol matrix tablet, with different concentration of hydrophobic and hydrophilic polymer were used with other excipients. The tablets were compressed by direct compression method after subjecting the blend to blend physical parameters studies like studies like angle of repose, bulk density, tapped density, Carr’s index. The results obtained were satisfactory. Post compression parameters like hardness, weight variation, friability, drug content analysis and in-vitro release profiles of drug from all the formulations could be best expressed by Higuchi’s equation, as the plots showed high linearity (R2: 0.942-0.995). To confirm the diffusion mechanism, the data were fit into Korsmeyer equation. The formulations F-1 to F-6 showed good linearity (R2: 0.961 to 0.993), which indicate the mechanism is diffusion coupled with erosion.

Formulation and Evaluation of Oral Controlled Release Clarithromycin Matrix Tablets using Hydrophilic Polymer

The objective of the present study was to develop clarithromycin tablets from polymeric hydrophilic matrices using methocel and characterization for its physic-chemical properties and in vitro release studies to optimize its release profile with the standard marketed product. Matrix tablets were prepared by wet granulation method using PVP and ethyl cellulose as binding agents. The matrix tablets were evaluated for its thickness, hardness, friability, weight variation, drug content and in vitro release studies. The drug delivery was analyzed using the paddle method in phosphate buffer pH 6.0 (dissolution medium I) and phosphate buffer pH 6.8 containing 0.5% sodium lauryl sulfate (dissolution medium II) and compared with USP dissolution limits. The dissolution release profile of formulation F9 was comparable with the market formulation and the difference factor and similarity factor f1 and f2 was found to be 2.44 and 83.18 in dissolution medium I; 1.44 and 89.71 in dissolution medium II. Stability studies were carried out as per ICH guidelines and tested for its physicochemical properties and in vitro studies. The study shows that the matrix method can be employed for preparing clarithromycin sustained release formulation using combination of hydrophilic polymers like Methocels and sodium carboxy methyl cellulose.

Improving drug loading of mucosal solvent cast films using a combination of hydrophilic polymers with amoxicillin and paracetamol as model drugs.

Solvent cast mucosal films with improved drug loading have been developed by combining carboxymethyl cellulose (CMC), sodium alginate (SA), and carrageenan (CAR) using paracetamol and amoxicillin as model drugs and glycerol (GLY) as plasticizer. Films were characterized using X-ray powder diffraction (XRPD), scanning electron microscopy (SEM), folding resilience, swelling capacity, mucoadhesivity, and drug dissolution studies. SA, CMC, and GLY (5 : 3 : 6) films showed maximum amoxicillin loading of 26.3% whilst CAR, CMC, and GLY (1 : 2 : 3) films had a maximum paracetamol loading of 40%. XRPD analysis showed different physical forms of the drugs depending on the amount loaded. Films containing 29.4% paracetamol and 26.3% amoxicillin showed molecular dispersion of the drugs while excess paracetamol was observed on the film surface when the maximum 40% was loaded. Work of adhesion was similar for blank films with slightly higher cohesiveness for CAR and CMC based films, but the differences were significant between paracetamol and amoxicillin containing films. The stickiness and cohesiveness for drug loaded films were generally similar with no significant differences. The maximum percentage cumulative drug release was 84.65% and 70.59% for paracetamol and amoxicillin, respectively, with anomalous case two transport mechanism involving both drug diffusion and polymer erosion.

Design and in vitro evaluation of formulations with pH and transit time controlled sigmoidal release profile for colon-specific delivery

The primary objective of the study was to develop a pH and transit time controlled sigmoidal release polymeric matrix for colon-specific delivery of indomethacin. Tablet matrices were prepared using a combination of hydrophilic polymers (polycarbophil or carbopol) having pH-sensitive swelling properties with hydrophobic polymer ethyl cellulose. The prepared matrices were characterized for physical properties and in vitro release kinetics. The presence of ethyl cellulose in a hydrophilic polymer matrix resulted in a sigmoidal in vitro drug release pattern with negligible-to-very low drug release in the initial phase (0–6 h) followed by controlled release for 14–16 h. The retardation in initial release can be attributed to the presence of ethyl cellulose that reduced swelling of hydrophilic polymer(s), while in the later portion, polymer relaxation at alkaline pH due to the ionization of acrylic acid units on carbopol and polycarbophil resulted in enhanced drug release. Thus, a sigmoidal release pattern was obtained that could be ideal for colonic delivery of indomethacin in the potential treatment of colon cancer.

Design and in vitro evaluation of formulations with pH and transit time controlled sigmoidal release profile for colon-specific delivery

The primary objective of the study was to develop a pH and transit time controlled sigmoidal release polymeric matrix for colon-specific delivery of indomethacin. Tablet matrices were prepared using a combination of hydrophilic polymers (polycarbophil or carbopol) having pH sensitive swelling properties with hydrophobic polymer ethyl cellulose. The prepared matrices were characterized for physical properties and in vitro release kinetics. The presence of ethyl cellulose in a hydrophilic polymer matrix resulted in a sigmoidal in vitro drug release pattern with negligible to very low drug release in the initial phase (0–6 h) followed by controlled release for 14–16 h. The retardation in initial release can be attributed to the presence of ethyl cellulose that reduced swelling of hydrophilic polymer(s) while in the later portion, polymer relaxation at alkaline pH due to the ionization of acrylic acid units on carbopol and polycarbophil resulted in enhanced drug release. Thus, a sigmoidal release pattern was obtained that could be ideal for colonic delivery of indomethacin in the potential treatment of colon cancer.

Formulation and Evaluation of Swellable and Floating Gastroretentive Ciprofloxacin Hydrochloride Tablets

Drugs that have narrow absorption window in the gastrointestinal tract (GIT) will have poor absorption. For these drugs, gastroretentive drug delivery systems offer the advantage in prolonging the gastric emptying time. Swellable, floating, and sustained release tablets are developed by using a combination of hydrophilic polymer (hydroxypropyl methylcellulose), swelling agents (crospovidone, sodium starch glycolate, and croscarmelose sodium) and effervescent substance (sodium bicarbonate). Formulations are evaluated for percentage swelling, in vitro drug release, floating lag time, total duration of floating, and mean residence time (MRT) in the stomach. The drug release of optimized formulation follows the Higuchi kinetic model, and the mechanism is found to be non-Fickian/anomalous according to Krosmeyer-Peppas (n value is 0.68). The similarity factor (f (2)) is found to be 26.17 for the optimized formulation, which the release is not similar to that of marketed produced (CIFRAN OD). In vivo nature of the tablet at different time intervals is observed in the radiographic pictures of the healthy volunteers and MRT in the stomach is found to be 320 +/- 48.99 min (n = 6). A combination of HPMC K100M, crospovidone, and sodium carbonate shows the good swelling, drug release, and floating characters than the CIFRAN OD.