Ruchi Tiwari

Drug delivery systems: An updated review

Drug delivery is the method or process of administering a pharmaceutical compound to achieve a therapeutic effect in humans or animals. For the treatment of human diseases, nasal and pulmonary routes of drug delivery are gaining increasing importance. These routes provide promising alternatives to parenteral drug delivery particularly for peptide and protein therapeutics. For this purpose, several drug delivery systems have been formulated and are being investigated for nasal and pulmonary delivery. These include liposomes, proliposomes, microspheres, gels, prodrugs, cyclodextrins, among others. Nanoparticles composed of biodegradable polymers show assurance in fulfilling the stringent requirements placed on these delivery systems, such as ability to be transferred into an aerosol, stability against forces generated during aerosolization, biocompatibility, targeting of specific sites or cell populations in the lung, release of the drug in a predetermined manner, and degradation within an acceptable period of time.

Cyclodextrins in delivery systems: Applications.

Cyclodextrins (CDs) are a family of cyclic oligosaccharides with a hydrophilic outer surface and a lipophilic central cavity. CD molecules are relatively large with a number of hydrogen donors and acceptors and, thus in general, they do not permeate lipophilic membranes. In the pharmaceutical industry, CDs have mainly been used as complexing agents to increase aqueous solubility of poorly soluble drugs and to increase their bioavailability and stability. CDs are used in pharmaceutical applications for numerous purposes, including improving the bioavailability of drugs. Current CD-based therapeutics is described and possible future applications are discussed. CD-containing polymers are reviewed and their use in drug delivery is presented. Of specific interest is the use of CD-containing polymers to provide unique capabilities for the delivery of nucleic acids. Studies in both humans and animals have shown that CDs can be used to improve drug delivery from almost any type of drug formulation. Currently, there are approximately 30 different pharmaceutical products worldwide containing drug/CD complexes in the market.

Bioanalytical method validation: An updated review.

The development of sound bioanalytical method(s) is of paramount importance during the process of drug discovery and development, culminating in a marketing approval. The objective of this paper is to review the sample preparation of drug in biological matrix and to provide practical approaches for determining selectivity, specificity, limit of detection, lower limit of quantitation, linearity, range, accuracy, precision, recovery, stability, ruggedness, and robustness of liquid chromatographic methods to support pharmacokinetic (PK), toxicokinetic, bioavailability, and bioequivalence studies. Bioanalysis, employed for the quantitative determination of drugs and their metabolites in biological fluids, plays a significant role in the evaluation and interpretation of bioequivalence, PK, and toxicokinetic studies. Selective and sensitive analytical methods for quantitative evaluation of drugs and their metabolites are critical for the successful conduct of pre-clinical and/or biopharmaceutics and clinical pharmacology studies.

FTIR spectroscopy: A tool for quantitative analysis of ciprofloxacin in tablets

A simple, accurate and sensitive spectroscopic method has been proposed for the assay of ciprofloxacin in tablet by least square treatment of fourier transform infrared spectrometric data obtained at the wavenumber corresponding to the carbonyl group centered at 1707 cm-1. The method involves the extraction of the active ingredient with methanol followed by phosphate buffer pH 6.0. The excipients in the commercial tablet preparation did not interfere with the assay. The specifity, linearity, detection limits, precision and accuracy of the calibration curve, drug extraction, infrared analysis and data manipulation were determined in order to validate the method. Moreover, the statistical results were compared with other methods for quantification of ciprofloxacin.

Bioanalysis in drug discovery and development

Recent years have witnessed the introduction of several high-quality review articles into the literature covering various scientific and technical aspects of bioanalysis. Now it is widely accepted that bioanalysis is an integral part of the pharmacokinetic/pharmacodynamic characterization of a novel chemical entity from the time of its discovery and during various stages of drug development, leading to its market authorization. In this compilation, the important bioanalytical parameters and its application to drug discovery and development approaches are discussed, which will help in the development of safe and more efficacious drugs with reduced development time and cost. It is intended to give some general thoughts in this area which will form basis of a general framework as to how one would approach bioanalysis from inception (i.e., discovery of a lead molecule) and progressing through various stages of drug development.

Factorial designed 5-fluorouracil-loaded microsponges and calcium pectinate beads plugged in hydroxypropyl methylcellulose capsules for colorectal cancer

Introduction: The work was aimed to develop an enteric-coated hydroxypropyl methylcellulose (HPMC) capsules (ECHC) plugged with 5-fluorouracil (5-FU)-loaded microsponges in combination with calcium pectinate beads. Materials and Methods: The modified quasi-emulsion solvent diffusion method was used to prepare microsponges. A 32 factorial design was employed to study the formulation and the effects of independent variables (volume of organic solvent and Eudragit-RS100 content) on dependent variables (particle size, %entrapment efficiency, and %cumulative drug release). The optimized microsponge (F4) was characterized by scanning electron microscopy, powder X-ray diffraction, and thermogravimetric analysis. F4 was plugged along with the calcium pectinate beads in HPMC capsules coated with enteric polymer Eudragit-L100 (Ed-L100) and/or Eudragit-S100 (Ed-S100) in different proportions. An in vitro release study of ECHC was performed in simulated gastric fluid for 2 h, followed by simulated intestinal fluid for next 6 h and then in simulated colonic fluid (in the presence and absence of pectinase enzyme for further 16 h). The optimized formulation was subjected to in vivo roentgenographic and pharmacokinetic studies in New Zealand white rabbits to analyze the in vivo behavior of the developed colon-targeted capsules. Results: Drug release was retarded on coating with Ed-S100 in comparison to a blend of Ed-S100:Ed-L100 coating. The percentage of 5-FU released at the end of 24 h from ECHC3 was 97.83 ± 0.12% in the presence of pectinase whereas in the control study, it was 40.08 ± 0.02%. Conclusion: Thus, enteric-coated HPMC capsules plugged with 5-FU-loaded microsponges and calcium pectinate beads proved to be a promising dosage form for colon targeting.

Promising future of probiotics for human health: Current scenario

Probiotics are nonpathogenic microorganisms mostly of human origin which, when administered in adequate amounts, confer a health benefit on the host and enable to prevent or improve some diseases. Probiotics may be a natural temporary constituent of the resident intestinal microflora, but their concentration is not sufficient for therapeutic purposes. The microbiota, the intestinal epithelium, and the mucosal immune system constitute the gastrointestinal ecosystem. All three components are essential for complete functional and developmental maturity of the system. Probiotics are defined as live microbial food ingredients that have a beneficial effect on human health. The use of antibiotics, immunosuppressive therapy, and irradiation, among other means of treatment, may cause alterations in the composition and have an effect on the gastrointestinal tract flora. Therefore, the introduction of beneficial bacterial species to GI tract may be a very attractive option to re-establish the microbial equilibrium and prevent disease. The efficacy of probiotics in acute enteric infections and post-antibiotic syndromes is now established and there is emerging evidence for a role in necrotizing enterocolitis, irritable bowel syndrome, periodontal diseases, and some forms of inflammatory bowel disease.

Studies on development of controlled delivery of combination drug(s) to periodontal pocket

AIMnThe aim of this study to develop the controlled delivery of combination drug(s) to periodontal pocket.nnnMATERIALS AND METHODSnIn the present investigation mucoadhesive gel formulations were prepared using carboxy methylcellulose (CMC), methylcellulose (MC), hydroxyethylcellulose (HEC), polyvinylpirrolidone (PVP), polycarbophil (PC), and poloxamer. Each formulation was characterized in terms of polarizing light microscopy, gelation, gel melting, hardness, compressibility, adhesiveness, cohesiveness, syringeability, adhesion to a mucin disk, rheological studies, drug release, and antibacterial activities. Addition of CMC and PVP to the gel favored hexagonal phase formation. The gelation temperature was decreased linearly with an increasing concentration of drug(s), whereas, the melting temperature increased with the concentration of drug(s). Increasing the concentrations of each polymeric component significantly increased formulation hardness, compressibility, adhesiveness, mucoadhesion, and syringeability, yet a decreased cohesiveness. Increased time of contact between the formulation and mucin significantly increased the required force of detachment. Drug release from all formulations was non-diffusion controlled and significantly decreased as the concentration of the polymer was increased, due to the concomitant increased viscosity of the formulations and the swelling kinetics of PC, following contact with the dissolution fluid.nnnRESULTnAntibacterial studies revealed that a gel with 30% HEC had a growth inhibition zone on agar with all three strains.nnnCONCLUSIONnFormulations containing HEC exhibited superior physical characteristics for improved drug delivery to the periodontal pocket and are now the subject of long-term clinical investigations.

Neutraceutical approaches to control diabetes: A natural requisite approach

Objective: The aim of this study is to screen the polyherbal preparation for antidiabetic activity in rats. Materials and Methods: The blood glucose lowering activity of the polyherbal preparation-I (1:1:1 of wheat germ oil, Coraidrum sativum, and Aloe vera) was studied in normal rats after oral administration at doses of 1.0 ml/kg and 2.0 ml/kg and polyherbal preparation-I, II (wheat germ oil, fresh juice of C. sativum, and A. vera in the ratio of 2:2:1), and III (wheat germ oil, fresh juice of C. sativum and A. vera in the ratio of 1:2:2) on alloxan-induced diabetic rats, after oral administration at doses of 1.0 ml/kg and 2.0 ml/kg. Blood samples were collected from the tail vein method at 0, 0.5, 1, 2, 4, 8, 12, and 24 h in normal rats and in diabetic rats at 0, 1, 3, 7, 15, and 30 days. Blood plasma glucose was estimated by the GOD/POD (glucose oxidase and peroxidase) method. The data were compared statistically by using the one-way ANOVA method followed by the Dunnett multiple component test. Statistical significance was set at P < 0.05. Results: The polyherbal preparation-I produced significant (P < 0.05) reduction in the blood glucose level of normal rats and polyherbal preparation-I, II, and III produced significant (P < 0.01) reduction in the blood glucose level of diabetic rats during 30-day study and compared with that of control and glibenclamide. Conclusion: The polyherbal preparation-I showed a significant glucose lowering effect in normal rats and polyherbal preparation-I, II, and III in diabetic rats. This preparation is going to be promising antidiabetic preparation for masses; however, it requires further extensive studies in human beings.

Enteric coated HPMC capsules plugged with 5-FU loaded microsponges: a potential approach for treatment of colon cancer

O trabalho teve como objetivo o desenvolvimento de novas capsulas com revestimento enterico HPMC (ECHC) conectadas com microesponjas carregadas com fluoruracila (5-FU) em combinacao com grânuos de pectinato de calcio. O metodo de difusao de solvente modificado quasi-emulsao foi usado para formular microesponjas com base no planejamento fatorial 32 e determinaram-se os efeitos das variaveis independentes (volume de solvente orgânico e conteudo Eudragit RS100) sobre as variaveis dependentes (tamanho de particula, EE% e % CDR). As microesponjas otimizadas (F4) foram caracterizadas por SEM, PXRD, TGA e ligadas aos grânulos de pectinato de calcio em capsulas de HPMC e estas foram, ainda, revestidas com polimero enterico Eudragit L 100 (Ed-L100) e/ou Eudrgit S 100 (Ed S 100) em diferentes proporcoes. No estudo de liberacao in vitro de ECHC foi realizada em varios meios de liberacao sequencial SGF durante 2 h, seguido de SIF para as proximas 6 h, e, em seguida, em SCF (na presenca e na ausencia de enzima pectinase por mais 16 h). A liberacao do farmaco foi retardada em revestimento com a EDS-100, em comparacao com mistura de EDS-100: EDL-100, de revestimento. O percentual de 5-FU liberado de ECHC 3 ao final de 24 h foi 97,83 ± 0,12% em presenca de pectinase, enquanto que para o controle foi de 40,08 ± 0,02% do farmaco. A formulacao otimizada foi submetida a estudos Roentgenograficos in vivo, em coelhos brancos Nova Zelândia, para analisar o comportamento das capsulas desenvolvidas direcionadas ao colon. Os estudos de farmacocinetica em coelhos brancos da Nova Zelândia foram conduzidos para determinar a extensao da exposicao sistemica propiciada pela formulacao desenvolvida, em comparacao com solucao aquosa de 5-FU. Assim, capsulas entericas de HPMC revestidas e conectadas com microesponjas carregadas com 5-FU e grânulos de pectinato de calcio se mostraram promissoras como formulacao para liberacao do farmaco no colon no tratamento do câncer colorretal.