Effect of polymers on release pattern of domperidone fast dissolving films. Science Spectrum.

Main aim is to develop fast dissolving film (FDF) of domperidone. Both natural and synthetic film forming polymers are chosen to improve the properties of the film. As the chosen drug is BCS class II drug, the solubility of domperidone was initially enhanced by the kneading method (1:0.5, 1:0.75, 1:1) using ?-cyclodextrins. The complete drug release was achieved 98.86% within 30 mins, hence this ratio is taken for further development of FDF. The FDFs of domperidone were prepared by incorporating the optimized solid dispersion SDK3 by solvent casting method using HPMC K15 and gellan gum in different concentrations 10%, 12.5%, 15%, 17.5% and 20% w/w. From the optimized concentrations of these polymers, another formulation was developed by taking the above two film forming polymers in combination. The better result was found with the mixture FHG film formulation. The drug and excipient compatibility was studied by FTIR, DSC and X-ray analysis.

Formulation and evaluation of gastro retentive floating dosage forms of clarithromycin.

The objective of the present investigation is to formulate gastro retentive floating drug delivery systems (GRFDDS) of clarithromycin for the treatment of Helicobacter pylori, to prolong the gastric residence time after oral administration, at a particular site and controlling the release of drug especially useful for achieving controlled plasma level as well as improving bioavailability and to study the effect of formulation variables on floating lag time, t50 (time required to release 50% of the drug) and t90 (time required to release 90% of the drug). The GRFDDS contains hydroxypropyl methylcellulose (HPMC) and hydroxyl propyl cellulose (HPC) as a release retarding polymer. The concentration of sodium bicarbonate (NaHCo3) was optimized. The tablets were prepared by wet granulation method. The prepared tablets were evaluated for all their physicochemical properties, in vitro buoyancy, drug release and rate order kinetics. From the results, FHM4 was selected as an optimized formulation based on their 12 hrs drug release, minimal floating lag time and maximum total floating time. The optimized formulation followed first order rate kinetics with erosion mechanism. The optimized formulation was characterized with FTIR studies and no interaction between the drug and the polymers were observed.

Microspheres Review: As a Carrier in Novel Drug Delivery.

Colon specific drug delivery has gained increased importance not just for delivery of drug for the treatment of local diseases, associated with the colon but also potential site for systemic delivery of therapeutic drug. Treatment could be more effective if it is possible for drug to be directly delivered to colon. This article gives an overview on anatomy and physiology of the colon and approaches utilized for colon specific drug delivery. This article also discusses advantages and limitations of the different approaches and also deals with the microsphere, various methods used for preparations of microspheres and advantages and disadvantages of microspheres.

A recent review on dual release bilayered tablets.

According to the literature review of the past decade, the design of bilayer tablets are suitable for sequential release of two drugs in which one layer is immediate release layer and the second layer as sustained release layer1 . Bilayer tablets have been developed to achieve immediate and sustained delivery of different drugs with pre-defined release profiles. In the last decade, interested in developing a combination of two or more active pharmaceutical ingredients (API) in a single fixed dosage form has increased in the pharmaceutical industry, promoting patient convenience and compliance2 . Bilayer tablet is suitable for sequential release of two drugs in combination or to incorporate two incompatible substances in same tablet3. This article explains about different techniques of bilayer tablet and why the development and production of quality bilayer tablets needs to be carried out and to reduce the common bilayer problems, such as layer-separation, insufficient hardness, Inaccurate individual layer weight control, cross- contamination between the layers, reduced yield etc3

Optimization of hydrodynamically balanced tablets of clarithromycin: An approach to prolong and increase the local action by gastric retention.

The objective of the present investigation is to formulate gastro retentive floating tablets (GRFT) of clarithromycin for the treatment of Helicobacter pylori, to prolong the gastric residence time after oral administration, at a particular site. Controlled release of drug is especially useful for achieving controlled plasma level as well as for improving bioavailability. The effect of formulation variables on floating lag time, t50 and t90 are also studied. The GRFT contains hydroxypropyl methylcellulose (HPMC) and hydroxyl ethyl cellulose (HEC) as release retarding polymers. The concentration of sodium bicarbonate (NaHCO3) was initially optimized. The tablets were prepared by wet granulation method and evaluated for all their physicochemical properties, in vitro buoyancy, drug release and rate order kinetics. From the results, FHM4 was selected as an optimized formulation based on the polymer concentration, 12 hrs drug release, minimal floating lag time and maximum total floating time. The optimized formulation followed first order rate kinetics with erosion mechanism. The optimized formulation was characterized with FTIR studies and no interaction between the drug and the polymers was observed.

A Review on transdermal drug delivery system: A novel tool for improving bioavailability

Among all the dosages, oral is the best route of administration for its advantages but due to flow of its demerits like poor bioavailability due to first pass metabolism and unpredictable nature of gastrointestinal absorption. Moreover, oral route is cost prohibitive and inconvenient. Transdermal patches are medicated adhesive patches when it was placed on the skin layer it will deliver the drug into the blood stream through skin layer. To overcome the side effects caused by the oral route, drugs given through transdermal are preferred as transdermal patch. By employing sustained release polymers, transdermal patches can be prepared using solvent casting method. Drug excipients compatibility studies are very important to determine whether the excipients are suitable for that drug or not. These compatibility studies are very important to maintain the stability of dosage form. Evaluation studies are very important to determine the accuracy of dosage form at the same time therapeutic action also. Some of the parameters such as weight variation, physical appearance, drug content, moisture uptake, folding, endurance, swelling study and physical appearance, in vitro dissolution studies, ex vivo studies, and in vivo studies were evaluated.

Bi-Gels: A novel material for transdermal drug delivery.

Bi-gels semi solid formulation is combination of organogel and hydrogel with better application property such as pharmaceutical and cosmetics. The main objective of this review is specially focuses on application of bi-gels as drug delivery vehicles by transdermal route. It contains two different phases which are polar and nonpolar due to which, it possess some significant features such as ability to deliver the hydrophilic and hydrophobic drugs which also have improved permeability of drugs, better spreading ability, and water wash ability. Hence, bigels have both organogels and hydrogels they can enhanced hydration of stratum corneum and also had an ability to manipulate the drug release rate from the dosage from.

Formulation and evaluation of bilayer floating tablets of atorvastatin and captopril.

The aim of the present research work was to develop a bilayer floating dosage form of immediate-release Atorvastatin (ATR) and sustained release Captopril (CPT) in matrix form for the treatment of hyperlipidaemia and hypertension to reduce multiple dosing frequencies and enhance patient compliance. ATR belongs to the BCS Class II category having poor aqueous solubility, which was enhanced by using hydrophilic polymer PEG 8000 by kneading technique. A sustained layer of CPT was prepared by melt granulation technique using various concentrations of carnauba wax with HPMC K 100 M and Carbopol 934 P. All the parameters before and after compression were evaluated. ATR-PEG ratio of 1:0.25 showed a higher drug release of about 97.42% within 60 min. The optimized CPT sustained layer SR2 shown the highest drug release 98.2% in 12 h. In-vitro drug release studies carried out as per USP in pH 1.2 buffer using type II apparatus. The CPT layer exhibited release kinetics in the first order and followed the diffusion and erosion mechanism. The FTIR, XRD studies, and SEM analysis indicated the absence of strong interaction between drug and polymer and compatibility among them. The novel concept of Bi-layer gastric floating can be utilized for the formulation of ATR and sustained release of CPT with a floating period of >12 h and 45 s lag time.

Application of synthetic and natural polymers in preparation and characterization of domperidone fast dissolving films.

Objective: The present research work is mainly focused on solubility enhancement of domperidone which is a biopharmaceutical classification system Class II drug using natural and synthetic polymers.

Methods: The solubility was enhanced by the kneading method with the drug: polymer (1:0.5, 1:0.75, and 1:1) using ?-cyclodextrin. The fast dissolving films (FDFs) of domperidone were prepared by incorporating the solid dispersion (SD) SDK3 by solvent casting method using hydroxypropyl methylcellulose K15 M (HPMC) and gellan gum in various concentrations for preparing FDFs. Various pre- and post-compression parameters, drug and excipients compatibility studies were evaluated by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction analysis (XRD).

Results: The maximum drug release of 98.86 % was achieved within 30 min for 1:1 ratio of solid dispersion using ?-cyclodextrin, was optimized and taken for further development of FDFs. From the in vitro drug release studies films prepared with 10% w/w of HPMC K 15 (FH5) and 10% w/w of gellan gum (FG5) showed enhanced dissolution rate compared to other formulations. The formulation FHG with combination of polymers, namely, HPMC K 15 and gellan gum in 1:1 ratio showed drug release of 97.22% within 15 min only when compared with the optimized formulations. FTIR and DSC studies revealed that there were no interactions between drug and excipients. XRD studies revealed slight conversion of crystalline form to amorphous. The optimized formulation FHG found to be stable under accelerated stability studies.

Conclusions: The polymers in combination are a potential candidate for use in the formulation of FDF.

Formulation and evaluation of famotidine fast dissolving tablets using synthetic superdisintegrants.

Objective: The main aim of the present research work was to formulate fast dissolving tablets of famotidine by direct compression method and to evaluate the effect of synthetic super disintegrating agent on drug release pattern. Methods: The fast dissolving tablets were prepared by using crospovidone, croscarmellose sodium, sodium starch glycolate as superdisintegrants (2, 4 and 6 %w/w), mannitol 20 % and microcrystalline cellulose (44, 46 and 48 % w/w) as a directly compressible vehicle. All the prepared tablets were evaluated for hardness, friability, drug content uniformity, weight variation, disintegrating time, wetting time and in vitro drug release studies. Results: All the prepared fast dissolving tablets formulations were within the Pharmacopoeial standards limits. Based on in vitro drug release studies (>90 % within 30 min), the optimised formulations were optimised tested for the short term stability (at 40 ?C/75% RH for 3 mo) and drug excipient interaction (fourier transform infrared spectroscopy). Conclusion: Hence, formulation prepared with 6 % w/w of crosspovidine and 44 % w/w of microcrystalline cellulose as emerged as the overall best formulation (>90 % within 30 min) compared to marketed product (>70 % within 30 min). Short-term stability studies on the formulations indicated that there are no significant changes in drug content and in vitro drug release (p<0.05).

Pharmacognostic, Physicochemical and Antioxidant Screening of Hibiscus hiritus

Objective: Aim of the present study was to perform pharmacognostic, phytochemical evaluation and antioxidant screening of ethanol extracts of Hibiscus hiritus. Methods: The free radical scavenging activity of ethanolic extract of Hibiscus hiritus was measured by DPPH (1, 1-diphenyl-2-picryl-hydrazil) employing the method described by Blois, 1958. 0.1 mM solution of DPPH in ethanol was prepared and 1 mL of this solution was added to 3 mL of various concentrations (50, 100, 150, 200, 250, 500, 750 and 1000 ?g/mL) of methanol extract. After 30 min, absorbance was measured at 517 nm. The percentage of inhibition was calculated by comparing the absorbance values of the control and test samples. Ascorbic acid was used as a reference compound.

Formulation and Evaluation of Ranitidine Hydrochloride Fast Dissolving Tablets Using Fenugreek Seeds Mucilage.

The aim of the present research work was to formulate fast dissolving tablets of ranitidine HCl by direct compression method and to evaluate fenugreek seeds mucilage as a natural superdisintegrating agent. The fast dissolving tablets were prepared by using fenugreek seed mucilage powder, crospovidone, croscarmellose sodium, sodium starch glycolate as superdisintegrants (2 and 4% w/w) and microcrystalline cellulose (34 and 36% w/w) as a directly compressible vehicle. All the prepared tablets were evaluated for hardness, friability, drug content uniformity, weight variation, disintegrating time, wetting time and in vitro drug release studies. All the prepared fast dissolving tablets formulations were within the Pharmacopoeial standards limits. Based on in vitro drug release studies (>90 % within 30 min), the two formulations were tested for the short term stability (40 ?C/75% RH for 3 months) and drug excipient interaction (IR spectroscopy). From all the prepared formulations, the formulation FR8 prepared with 6% w/w fenugreek seeds mucilage and 34% w/w of MCC was optimised as the best formulation (>90 % within 30 min) compared to conventional commercial tablets formulation (>75 % within 30 min). There is no significant on drug content and in vitro drug release (p < 0.05) (Accelerated stability studies).

Microsponges as a neoteric cornucopia for drug delivery systems.

Microsponges (MSPs) are at the forefront of the rapidly developing field of novel drug delivery systems which are gaining popularity due to their use for controlled release and targeted drug delivery. The microsponge delivery system (MDS) is a patented polymeric system consisting of porous microspheres typically 10-25 microns in diameter, loaded with an active agent. They are tiny sponge-like spherical particles that consist of a myriad of interconnecting voids within a non-collapsible structure with a large porous surface through which active ingredient is released in a controlled manner. Microsponge also hold a certification as one of the potential approaches for gastric retention where many oral dosage forms face several physiological restrictions due to non-uniform absorption pattern, inadequate medication release and shorter residence time in the stomach. This type of drug delivery system which is non-irritating, non-allergic, non-toxic, can suspend or entrap a wide variety of substances, and can then be incorporated into a formulated product such as gel, cream, liquid or powder that is why it is called as a “versatile drug delivery system”. It overcomes the drawbacks of other formulations such as frequency of dosing, drug reaction, incompatibility with environmental condition. These porous microspheres were exclusively designed for chronotherapeutic topical drug delivery but attempt to utilize them for oral, pulmonary and parenteral drug delivery were also made. The present review elaborates about the multifunctional microsponge technology including its preparation, characterization, evaluation methods along with recent research and future potential.

Preparation and evaluation of drotaverine HCl Orally disintegrating tablets using melt granulation.

The objective of the present study is to formulate and evaluate orally disintegrating taste masked drotaverine hydrochloride (HCl) tablets prepared by the melt granulation technique. Taste-masked drug—polymer melt granules of drotaverine HCl were prepared by using either compritol 888 ATO (compritol) or precirol ATO 5 (precirol) using varying drug-polymer ratios of 1:1, 1:2, 1:5, and 1:7. Prepared drug-polymer blends were evaluated for taste masking and the ratio of drug-polymer is optimized. The drug-polymer ratios 1:7 with compritol and 1:5 with precirol were optimized based on taste evaluation. The granules and tablets prepared with optimized drug-polymer ratio were evaluated for pre- and post-compression parameters. From all the prepared taste masked drotaverine HCl tablets, formulations CP9 and PF5 were optimized based on taste, mouthfeel, dissolution, and other oral disintegrating tablet (ODT) parameters. Formulations CP9 and PF5 showed the release of >50% drug in 5 minutes and 100% of the drug in 45 and 30 minutes, respectively. The optimized formulations were characterized by Fourier transformed infrared spectroscopy, differential scanning calorimetry, and XRD studies and found no incompatibility. The results demonstrated that the prepared drotaverine HCl ODT showed better taste masking meeting the parameters of ODT formulations PF5 > CP9. The present melt granulation technique can be effectively used for taste masking.

Preparation and evaluation of drotaverine HCl ODT using solid mixture technique.

Objective: The objective of this study is to formulate orally disintegrating taste masked tablets of drotaverine HCl using solid mixture technique. Methods: Taste masked drug-polymer solid mixtures of drotaverine HCl were prepared by using hydroxypropyl methylcellulose (HPMC) 3 cps and rxcipient® FM1000/calcium silicate (rxcipient) as carriers employing kneading method using varying drug-polymer ratios of 1:1, 1:5, 1:7.5, and 1:9. Prepared drug-polymer mixtures evaluated for taste masking, and the ratio of drug-polymer is optimized. The granules and tablets prepared with optimized drug-polymer ratio were evaluated for pre- and post-compression parameters, in vitro dissolution studies, Fourier-transformation infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X-ray diffractometry (XRD) studies. Results: The drug:polymer ratios 1:7.5 with rxcipient and 1:9 with HPMC were optimized based on taste evaluation. The pre-compression results showed that all the formulae have good flow properties. The post-compression evaluations showed that all the formulae met the specifications of orally disintegrating tablets. From all the prepared taste masked drotaverine HCl tablets, R10 formulation consisting of 4% croscarmellose sodium and H9 formulation consisting of 3% croscarmellose sodium, 3% sodium starch glycolate, and 2% microcrystalline cellulose shown more than 99% drug release in 60 min, and both the formulations showed better taste masking and were meting oral disintegrating tablet (ODT) parameters. The optimized formulation was characterized by FTIR, DSC, and XRD studies and found no incompatibility. Conclusion: The results demonstrated that the prepared drotaverine HCl ODT showed better taste masking and meeting the parameters of ODT formulations R10 and H9. The present solid mixture technique can be effectively used for taste masking.

Preparation and evaluation of orally disintegrating tablets of drotaverine HCl using sublimation technique.

Objective: To formulate orally disintegrating taste masked tablets of drotaverine hydrochloride (HCl) by sublimation technique. Methods: Initially superdisintegrant was selected and its concentration was optimized by pre-compression and post-compression parametric evaluation. Camphor and menthol were used as sublimating agents alone and in combination to mask the taste of drotaverine hydrochloride. Prepared tablets were evaluated for physicochemical evaluation, in vitro dissolution studies and fourier transformation-infrared spectroscopy, differential scanning calorimetry and X-ray diffractometry studies. Results: The optimised formulation DCM2 prepared with a mixture of camphor and menthol was characterised by fourier transformation-infrared spectroscopy, differential scanning calorimetry and X-ray diffractometry studies and found no incompatibility and no major shifts were noticed. Conclusion: The results demonstrated that the prepared drotaverine HCl orally disintegrating tablets showed better taste masking. The present sublimation technique can be effectively used for taste masking and also for orally disintegrating tablets.

Natural Polymers: A Recent Review.

Active ingredient and excipients are two main ingredients of any pharmaceutical formulation. Excipients help in the manufacturing of dosage form as well as improve physicochemical parameters of the dosage form. Polymers play a vital role in any dosage form as excipients. The influencing capacity of polymers towards the drug release and should be compatible, non-toxic, and stable and economic etc. They are broadly classified in three categories viz. natural polymers, semi-synthetic and synthetic polymers. Natural polymers are generally used as rate controlling agents, taste masking agents, protective and stabilizing agents in the oral drug delivery system. To provide uniform drug delivery certain polymers are used to reduce the frequency of dosing and to increase effectiveness of the drug by localization at the site of action. Nowadays, due to many problems associated with drug release and side effects of synthetic polymers, manufactureres are inclined towards using natural polymers. Natural polymers being poly saccharides are biocompatible and without any side effects. Applications of natural polymers in pharmacy are large in comparison to the synthetic polymers and have wide scope in food and the cosmetic industry.

DESIGN AND EVALUATION OF TIME DEPENDENT ORAL COLON TARGETED DRUG DELIVERY SYSTEMS FOR TINIDAZOLE USING EUDRAGIT® NE 30D

Tinidazole is an anti-infective drug which is widely used in the treatment of colonic disorders like amoebiasis, an infection of the large intestine caused by Entamoeba histolytica, a single celled protozoan parasite. The main aim of the present work is to design and evaluate timed release oral colon targeted drug delivery system for tinidazole which would release negligible amount of drug in the first 6 hours lag period when the drug is in the upper GIT followed by complete release of the drug in the colon, in a controlled manner in the next 18hours. The tinidazole core tablets are prepared by wet granulation and then coated with Eudragit® NE 30D to achieve time dependent release profile for colon targeting. The prepared tablets were evaluated for various tabletting parameters and based on the pharmacopeial tests conducted and the study of release kinetics of the prepared tablets, FE4 having the Eudragit® NE30D polymer coat load of 25%w/w was selected as the optimized formula as it showed timed release profile for achieving colon targeting of tinidazole.

Solid dispersions: An evergreen solubility enhancement technique for hydrophobic drugs

Oral route is the most preferable route of drug delivery for most of the drug but it is not suitable for the drugs which are poorly water soluble. It mainly affects the oral bioavailability of the drugs. It remains as a most challenging aspect in formulation development due to its minimal solubility. To overcome this problem formulation scientists have employed the different techniques. One of the techniques is solid dispersions. These are gaining attracted considerable interest as an efficient means of improving the solubility and dissolution which results in increasing the bioavailability of poorly water soluble drugs. The present article mainly focus on the areas of basic concept of solid dispersions, advantages, disadvantages, types and various methods of preparation for solid dispersions.

DEVELOPMENT, FORMULATION AND EVALUATION OF A BILAYER GASTRIC RETENTIVE FLOATING TABLETS OF RANITIDINE HCL AND CLARITHROMYCIN USING NATURAL POLYMERS

Objective: Bilayer gastric retentive floating tablets (BGRFT) with ranitidine HCl and clarithromycin using natural gums have been developed to prolong the gastric residence time and increase drug bioavailability. Literature review revealed no published studies on the present study. Methods: Immediate release (IR) layer prepared by using different diluents and super disintegrants like sodium starch glycolate, crosscarmellose sodium and crospovidone. Controlled released (CR) layer prepared by using neem gum, damar gum and copal gum. Prepared tablets were evaluated for in vivo and in vitro buoyancy, in vitro dissolution studies and fourier transformation-infrared spectroscopy (FTIR). Drug release was evaluated with zero and first order for release kinetics, Higuchi, Hixson-Crowell erosion models for release mechanism. Results: Prepared IR layer followed first order rate kinetics and CR layer followed zero order rate kinetics with non-Fickian diffusion mechanism. BGRFT also showed similar results as that of the individual layer. Optimized formulations were characterized by FTIR studies and found no interactions between drug and polymer. Conclusion: The results demonstrate the feasibility of the model in the development of BGRFT. BGRFT enhanced the drug release and finally the bioavailability of clarithromycin when compared with commercial tablet (Biomycin 250). The present study could establish the suitability of neem gum as CR polymer in the design of BGRFT.

Echogenic bubbles: An new avenue for cancer therapy.

Ecogenic bubbles and their application in the treatment of cancer.

Ecogenic bubbles and their application in the treatment of cancer.