R Manavalan

Annamalai University, Anamalainagar, Tamil Nādu, India

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Publications (117)56.55 Total impact

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    ABSTRACT: Export Date: 18 October 2014
    International Journal of Pharma and Bio Sciences 01/2014; 5(1):P606-P611. · 0.01 Impact Factor
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    ABSTRACT: The purpose of this research work was to prepare Oxcarbazepine niosomes to improve the anticonvulsant activity. The nonionic surfactant vesicles were prepared by the thin film hydration method. The lipid mixture consists of drug, cholesterol, and surfactant in the molar ratio of 1:1:3 respectively to achieve prolonged circulation time and sustained release. The in vivo study revealed that the prepared niosomal dispersion shows improved anticonvulsant activity of Oxcarbazepine in albino wistar rats. After a single dose of the niosomal dispersion, it showed significant increase in the mean residence time (MRT) of Oxcarbazepine reflecting sustained release characteristics. In conclusion the niosomal formulation could be a promising delivery system for Oxcarbazepine with improved anticonvulsant activity, oral and prolonged drug release profiles.
    Journal of Pharmaceutical Sciences and Research 01/2013; 5(1):8-11.
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    ABSTRACT: Low-density lipoprotein cholesterol (LDL-C) remains the primary target of lipid-lowering therapy. Achieving LDL-C goals as outlined by the National Cholesterol Education Program Adult Treatment Panel III can be difficult with statins alone; therefore, adjunctive therapy is often indicated to reduce cardiovascular risk. This review provides an overview of beneficial effects of ezetimibe in patients with dyslipidemia when attempting to normalize serum lipid profiles and reduce risk for cardiovascular disease. Ezetimibe, a potent inhibitor of intestinal cholesterol absorption, has been shown to be safe, tolerable and effective at lowering LDL-C, non-high-density lipoprotein cholesterol and apolipoprotein B, each of which has been correlated with improved clinical outcomes, alone or in combination with a statin. Ezetimibe coadministered with statins, a dual inhibition treatment strategy that targets both cholesterol absorption and synthesis, is an effective therapeutic option for dyslipidemia.
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    ABSTRACT: The intestinal absorption of oral-anti diabetic drugs in the treatment of type-II diabetes mellitus is altered when they are concomitantly administered with synthetic drugs, food supplements and others. Diabetic health care consumers needs sweetening agents to take drugs, foods and eatables. A randomized cross over study in two phases and a washout period of 4 weeks was carried out to evaluate the bioavailability of anti diabetic drug Metformin hydrochloride when used with stevias a drug for ulcer. The study has been approved by the institutional ethical committee of Raja Muthiah Medical College & Hospital, Annamalai University. In the present study 10 healthy human volunteers received stevias (1g) for 5 days. After overnight fasting on 6 th day a single dose of Metformin hydrochloride (500mg) was given. The blood samples following the intake were taken at different time intervals of 1, 2, 3, 4, 5, 7, 9 and 12 hours. The plasma samples (100μl) were injected into HPLC system after separation. The mobile phase comprised of Methanol: acetonitrile: mixed phosphate buffer (pH 2.6) at a ratio of (40:12:48). Analyses were run using cyano column (7.5mm x 4.6mm i.d, 5μm) at a flow rate of 1.2 ml.min-1 with diode array detector operating at a detection wave length of 234 nm in HPLC and the pharmacokinetic parameters were calculated by using the software Kinetica (Version 4.4.1Innaphase, USA). This study reveals that there is no significant change in the plasma concentration of Metformin hydrochloride when it was concomitantly administered with Stevias.
    Journal of Pharmaceutical Sciences and Research 12/2012; 4(1):1676-1680.
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    ABSTRACT: To prepare curcumin-piperine (Cu-Pi) nanoparticles by various methods and to study the effect of various manufacturing parameters on Cu-Pi nanoparticles and to identify a suitable method for the preparation of Cu-Pi nanoparticles to overcome oral bioavailability and cancer cell targeting limitations in the treatment of cancer. Cu-Pi nanoparticles were prepared by thin film hydration method, solid dispersion method, emulsion polymerization method and Fessi method. Optimization was carried out to study the effect of various manufacturing parameter on the Cu-Pi nanoparticles. Out of four methods, Fessi method produced a minimum average particle size of 85.43 nm with a polydispersity index of 0.183 and zeta potential of 29.7 mV. Change of organic solvent (acetone or ethanol) did not have any significant effect on Cu-Pi nanoparticles. However, increase in sonication time, stirring speed, viscosity, use of 1:10:10 ratio of drug/polymer/surfactant, and use of anionic surfactant or combination of anionic surfactant with cationic polymer or combination of non-ionic surfactant with cationic polymer had a significant effect on Cu-Pi nanoparticles. Cu-Pi nanoparticles coated with PEG containing copolymer produced by Fessi method had a minimum average particle size, excellent polydispersity index and optimal zeta potential which fall within the acceptable limits of the study. This dual nanoparticulate drug delivery system appears to be promising to overcome oral bioavailability and cancer cell targeting limitations in the treatment of cancer.
    Asian Pacific Journal of Tropical Biomedicine 11/2012; 2(11):841-8. DOI:10.1016/S2221-1691(12)60241-X
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    ABSTRACT: Oseltamivir is an antiviral drug, a neuraminidase inhibitor used in the treatment and prophylaxsis of both influenza A and influenza B. The objective of this research was to formulate and evaluate the Oseltamivir phosphate capsules. The Oseltamivir capsules were prepared by using various excipients namely, Pregelatinised Starch, Croscarmellose sodium, Povidone K-30, Talc and Sodium stearyl fumerate. Drug excipients compatibility studies were conducted to select the most appropriate excipients. Based on the preliminary studies, various formulation trials were carried out with different concentrations of disintegrants and lubricants. The formulation was carried out by both dry granulation and wet granulation technique. The capsule filling was done by manual capsule filling machine. Among all the formulation, formulation F5 showed satisfactory results with various physicochemical evaluation parameters like disintegration time, dissolution profile and assay when compared with that of the marketed product. The in vitro release profiles of drug could be best expressed by Korsmeyer-peppas equation as the plots showed high linearity (R 2 = 0.975). The stability studies show that the capsules were found to be stable. The present study was to develop a pharmaceutically equivalent, low cost, quality improved and stable formulation of Oseltamivir Phosphate capsules.
    International Journal of Pharmacy and Pharmaceutical Sciences 10/2012; 4(2):342-347. · 1.59 Impact Factor
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    ABSTRACT: The object of this present study was to develop extended release matrix film coated tablets of Eperisone hydrochloride to enhance the therapeutic efficacy, reduce the frequency of administration and improve the patient compliance. The matrix film coated tablets were prepared by wet granulation method, using different polymers such as Hydroxyl propyl methyl cellulose (HPMC K4M, K100M), Ethyl Cellulose (EC), Microcrystalline cellulose pH 101 (MCC), alone or in combinations and other standard excipients. The granules of different formulations were determined for bulk density, tapped density, compressibility Index and Hausner ratio. Formulated tablets were evaluated for physical characteristics viz. hardness, thickness, friability, percentage weight variation and drug content. Further, tablets were evaluated for In-vitro release characteristic for 12 hrs. Tableting of granules was showed good flow properties and fabricated tablets were exhibited desired compressibility characteristics. Formulation (F5) exhibited an In-vitro drug release up to of 90% and the release kinetics of drugs was best explained by Krosmeyer-peppas model. The optimized formulation was passed the stability studies carried out at room temperature (25ºC±2º/60º±5%RH) as per ICH guidelines and an accelerated stability conditions (40ºC±2º/ 75%±5%RH) for 3 months. The designed Eperisone hydrochloride matrix film-coated tablets have a potential for Extended-release dosage forms.
    International Journal of Pharmacy and Pharmaceutical Sciences 04/2012; 4(2):575-581. · 1.59 Impact Factor
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    ABSTRACT: Developed and optimized a validated isocratic reverse phase HPLC separation of Rosuvastatin, Telmisartan, Ezetimibe and Atorvastatin in pharmaceutical preparation using response surface methodology. The separation was carried out by using phenomenex C18 column (15 cm × 4.6 mm id, 5 μm particle size) and UV detection at 239 nm. The ranges of the independent variables used for the optimization were MeCN: 33–38%, buffer conc.: 10–20 mM and flow rate: 1–2 ml/min. The influence of these independent variables on the output responses: capacity factor of the first peak (k1), resolutions of the 2nd and 3rd peak (Rs2,3), and capacity factor of the fifth peak (k5) were evaluated. Using this strategy, a mathematical model was defined and a response surface was derived for the separation. The three responses were simultaneously optimized by using Derringer’s desirability functions. Optimum conditions chosen for the assay were MeCN, MeOH, 20 mM K2HPO4 (pH 3.0 ± 0.2) solution (34.27:20:45.73 v/v/v) and flow rate 2 ml/min. Total chromatographic analysis time per sample was approximately 10 min. The optimized assay condition was validated as per the ICH guidelines and applied for the quantitative analysis of Rosavel EZ, Avas-EZ and Lipisar 20 tablet. The developed method was simple, accurate and precise. Hence, it can be employed for the routine analysis in quality control laboratories.
    Arabian Journal of Chemistry 03/2012; 107. DOI:10.1016/j.arabjc.2012.03.001 · 2.68 Impact Factor
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    ABSTRACT: Written information play a significant role in supplementing and reinforcing information provided by healthcare professionals. Patient information leaflets (PILs), an inexpensive form of written information which aids the patients and their caregivers to understand the disease and medication. However, poorly designed leaflets may lead to lack of adherence to the proposed treatment. Information in PILs must confirm to the highest standards of scientific accuracy, comprehensive, and designed in a way that is easy to read and understand. Hence, the primary aim of the present study was to assess the quality of patient information leaflet supplied by pharmaceutical manufacturers with respect to readability, design and contents. The study included 35 PILs collected from patients, community pharmacies and hospitals. Readability of PILs was assessed using flesch readability ease formula and flesch kincaid grade level formula. Design and contents of PILs were assessed using predefined score table. The study results showed that 88% of the PILs had reading difficulty, 74% of the PILs had poor design and 60 % of the PILs did not have the necessary information.
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    Research Journal of Pharmacy and Technology 01/2012; 5(4):547-552.
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    ABSTRACT: Amlodipine besilate is a calcium channel blockers used for the treating high blood pressure, certain types of angina and coronary heart failure. Atorvastatin calcium known as Statins is used for lowering blood cholesterol and in the treatment of primary hypercholesterolemia and dyslipidemia. The objective of the present investigation was to formulate and evaluate an oral administrable tablet containing Amlodipine besilate and Atorvastatin calcium by wet granulation method. The tablets were prepared using Microcrystalline cellulose, Calcium carbonate, polysorbate 80, Hydroxypropyl cellulose, Pregelatinized starch, Croscarmellose sodium, Colloidal anhydrous silica and Magnesium stearate. Preformulation studies were performed prior to compression. The prepared tablets were evaluated for various pre-compression characteristics like angle of repose, bulk density, tapped density, cars index and hausner's ratio, loss on drying and post-compression characteristics like Appearance, Weight variation, Hardness, Thickness, Disintegration, Friability, In vitro Dissolution studies. The stability studies were carried out for the optimized batch for three months and it showed no significant changes in the physicochemical parameters and in vitro release pattern. The present study concludes that combined pill has the potential to improve the management of hypertensive patients with additional cardiovascular risk factors, especially dyslipidemia by reducing pill burden and prescription costs.
    Research Journal of Pharmaceutical, Biological and Chemical Sciences 01/2012; 3(1):425-434. · 0.35 Impact Factor
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    ABSTRACT: BACKGROUND: Drug therapy has become so difficult that no one professional is expected to optimize the drug therapy and control drug related problems (DRPs) alone. Despite excellent benefits and safety profile of most medications, DRPs pose a significant risk and adversely affect quality of life of patients. Pharmacists seek to implement pharmaceutical care and measure their effects on patient outcomes. OBJECTIVE: The objective of the study was to identify DRPs amongst inpatients, and the clinical outcome derived from pharmaceutical reactive intervention and passive interventions. METHODOLOGY: The prospective study involves collection of medication details of all the patients and reviewed independently by the pharmacist to identify DRPs and discussed with the physician and suitable reactive interventions were provided and each intervention was graded based on the expected clinical outcome. Similarly passive interventions involved provision drug information services to health care professionals. RESULTS: A total of 386 interventions were made of which 261 were reactive interventions (261DRPs were identified from 189 patients) and 125 were passive interventions. The most common DRPs was drug use without indication (18%) and most common reactive intervention was cessation of drug (20%) and the most frequent passive intervention (drug information query) was related to education and recent advances (51.2%). CONCLUSION: The study demonstrates that reactive interventions of clinical pharmacist improved the patient outcome and passive interventions influenced physicians' decision making in drug therapy.
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    ABSTRACT: Selecting the right method for the preparation of nanoparticles is a crucial decision. A wrong decision can result in the product having to be formulated and developed again. One tool that can be useful in determining the most appropriate method is the Analytical Hierarchy Process (AHP). AHP has been employed in almost all areas related to decision-making problems. In this paper, the results of a case study illustrate that the AHP concept can assist designers in the effective evaluation of various methods available for the preparation of nanoparticles. This paper presents the methodology of selecting the most suitable method for preparing nanoparticles using the analytical hierarchy process.
    Pharmazie 11/2011; 66(11):836-42. DOI:10.1691/ph.2011.1034 · 1.00 Impact Factor
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    ABSTRACT: Targeting of drugs to specific sites of action provides several advantages over non-targeted drugs. Colon specific drug delivery had gained increased importance just for the delivery of drugs for the treatment of local diseases associated with the colon. For the successful targeting of drugs to the colon, the drug needs to be protected from degradation, release and or absorption in the upper portion of GI tract and then to ensure the abrupt or controlled release in the proximal colon. General approaches for colon targeting drug delivery includes use of prodrugs, pH dependent system, time dependent systems and colonic microflora activated systems. Multifunctional nanoparticles play a significant role in cancer drug delivery. Nanoparticles exploit biological pathway to achieve payload delivery to cellular and intracellular targets. The targeting schemes explored for many of the reported nanoparticles systems suggest the great potential of targeted delivery to revolutionize cancer treatment. This review article deals with anatomy and physiology of colon, development of colon cancer, various approaches for colon targeting and evaluation of drug release in colon to give a updated information for the need and development of drug loaded nanoparticles for colon cancer.
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    P Venkatesan, R Manavalan, K Valliappan
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    ABSTRACT: The aim of present study was to formulate and evaluate the loxoprofen loaded Sustained release microspheres by emulsion solvent evaporation technique. Ethylcellulose, a biocompatible polymer is used as the retardant material. The effects of process conditions such as drug loading, polymer type and solvent type on the characteristics of microspheres were investigated. The prepared microspheres were characterized for their particle size and drug loading and drug release. The in-vitro release studies were carried out in phosphate buffer at pH 7.4. The prepared microspheres were white, free flowing and spherical in shape. The drug-loaded microspheres showed 71.2% of entrapment and the in-vitro release studies showed that Loxoprofen microspheres of 1:3 ratios showed better sustained effect over a period of 8 hours.
    06/2011; 2(3):159-62.
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    ABSTRACT: Recent developments in the technology have initiated scientists to develop orally disintegrating tablets (or) orodispersible tablets with an improved patient compliance and convenience. There are various methods available for the formulation of orodispersible tablets like direct compression, lyophilization (or) freeze drying, sublimation and vaccum drying etc. It is important to incorporate all the quantitative and qualitative criteria such as formulation information, manufacturing skill, supplier, technical information, technical status and machine in the selection process. The fuzzy set theory allows to incorporate unquantifiable, incomplete and partially known information into the decision model. Hence, in the present study fuzzy analytic hierarchical process (FAHP) was applied to select best method for the formulation of orodispersible tablets. Based on the results of FAHP it is concluded that direct compression method is the best method for the formulation of orodispersible tablets.
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    ABSTRACT: Global cancer population is more than 6.75 billion and it is the leading cause of death worldwide. Efforts are being made with the aim to prevent, control and cure the cancer through research activities with the contributions from industries, government and philanthropic funders. However, academic researchers prefer In-vitro cell based assays as they are economically good enough to establish the anticancer activity of a compound/ drug. Assessment of in-vitro anticancer activity is based on the concept of ‘basal’ cytotoxicity of the compounds/ drug which affects the basic functions of cells which in turn leads to cellular damage. Hence anticancer activity/ cytotoxicity can be evaluated by measuring the basic parameter of cellular damage such as increased ATP levels, change in mitochondrial activity, increased concentration of LDH and uptake of fluorescent dye after DNA fragmentation. This review focuses the principle, brief methodology, and latest utilization of the most commonly employed in-vitro cell based anticancer drug screening techniques.
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    ABSTRACT: The purpose of the present study was to systematically investigate some of the important physicochemical properties of loxoprofen loaded microspheres. Loxoprofen, 2-[4-(2-oxocyclopentylmethyl) phenyl]-propionate with two chiral centers, is marketed as an equal parts mixture of four stereoisomers. Loxoprofen sodium is an important non-steroidal anti-inflammatory drug (NSAID) of the 2-arylpropionic acid group used for the treatment of rheumatoid arthritis and osteoarthritis. Almost all drugs are marketed as tablets, capsules or both. Prior to the development of these major dosage forms, it is essential that pertain fundamental physical and chemical properties of the drug molecule and other divided properties of the drug powder are determined. This information decides many of the subsequent events and approaches in formation development.A sustained release microsphere of Loxoprofen was prepared by solvent evaporation method using ethyl cellulose as coating material. So before selection of excipients, the Preformulation study of drug loxoprofen is completed for successful formulation of sustained release microspheres. Preformulation studies included solubility, pKa, dissolution, melting point, assay development, stability in Solution, stability in solid state; microscopy, bulk density, flow properties, excipient compatibility, entrapment efficiency and release profile of microspheres were investigated. INTRODUCTION Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used for the treatment of pain and inflammation. NSAIDs produce their therapeutic effect by inhibiting the cyclooxygenase (COX) enzymes, which are involved in the biosynthesis of prostaglandins (PGs) [1,2]. Loxoprofen, 2-[4-(2-oxocyclopentylmethyl) phenyl]-propionate with two chiral centres, is marketed as an equal parts mixture of four stereoisomers. Loxoprofen sodium is an important non-steroidal anti-inflammatory drug (NSAID) of the 2-arylpropionic acid group used for the treatment of rheumatoid arthritis and osteoarthritis. Loxoprofen is a prodrug which produces effects after being absorbed from the gastrointestinal tract followed by conversion to an active metabolite. The mechanism of action of loxoprofen is due to inhibition of prostaglandin biosynthesis by its action on cyclooxygenase. After oral administration, loxoprofen sodium is absorbed as the free acid from the gastrointestinal tract rather than the sodium salt, which causes just weak irritation of the gastric mucosa, and is then converted to an active metabolite by reduction of the ketone carbonyl to the trans-OH form. The active isomer has the 2S, 1R', 2'S configuration, which potently inhibits prostaglandin biosynthesis [3–5]. Loxoprofen has an activity to treat inflammatory rheumatoid diseases and relieve acute pain. It is effective against period pains, pain after surgery and fever. Loxoprofen available in pharmaceutical formulations as Tablets and Transdermal patches [6, 7]. Preformulation commences when a newly synthesized drug shows sufficient pharmacologic promise in animal models to warrants evaluation in man. These studies should focus on those physicochemical properties of the new compound that could affect drug performance and development of an efficacious dosage form. A thorough understanding of these properties may ultimately provide a rational for formulation design, or support the need for molecular modification [8].
    International Journal of Research in Pharmaceutical and Biomedical Sciences 01/2011; 2:107-117.