Background: The conventional oral dosage forms are not effective in dealing with chronopathological conditions, such as nocturnal asthma. Therefore, there is an unmet need to develop a delivery system that can deliver drug as per the chronopharmacology of the diseases. The purpose of the study is to use quality by design (QbD) technique and pulsatile principles for the development of Eudragit-coated dual release bilayer tablets. The dual layer consists of immediate release layer of fexofenadine HCl and sustained release layer of montelukast sodium. Results: The quality target product profile of the formulation was developed, and the critical quality attributes were identified. Three-level, three-factor Box-Behnken design was used for the optimization of the bilayer tablets. Based on the design, a total of 13 formulation combinations (F1-F13 and M1-M13) were made having acceptable micromeritic properties. The developed immediate and sustained release layers were evaluated for physicochemical properties. Depending upon the value of the diffusion exponent, the Fickian diffusion mechanism is dominant among immediate and sustained release tablet layers. Response curve for immediate release layer showed that concentrations of sodium starch glycolate and sodium bicarbonate had a negative effect on disintegration time and a positive effect on drug release. For sustained release tablet layer, concentrations of HPMC E 5 LV and magnesium stearate had a significant effect on drug release. The ANOVA and diagnostic plots confirmed the significance and goodness of fit of the used model. Based on desirability plot values, optimized formulation was developed and coated with Eudragit coat. The coated bilayer tablet showed met the requirement of providing an immediate release during the first hour and a sustained release action for a period of more than 8 h after passing the gastric region. Conclusions: The formulation can be fruitful in curbing the menace of nocturnal asthma and providing a high degree of patient compliance as the patient will not have to wake up at night to take the medication.

:Objective: The purpose of this study was to prepare Eudragit S-100 coated salbutamol sulphate matrix tablet for chronotherapeutic drug delivery system for the treatment of nocturnal asthma. Methods and Material:This study is designed to analyze the effect of Eudragit S-100 coating on the drug release from hydroxypropyl methylcellulose matrix to achieve the time and pH dependent chronotherapeutic drug delivery system of salbutamol sulphate. Hydroxypropyl methylcellulose matrix tablets of salbutamol sulphate were prepared by wet granulation method and coated with Eudragit S-100 using dip coating method. Then the tablets were evaluated for different physical parameters, compatibility studies and in vitro dissolution. Results: Matrix tablets of salbutamol sulphate have been characterized for weight variation, hardness, friability and drug content. HPMC matrix tablet failed to control the drug release in initial hrs. and shows 68 ± 0.71% of the drug release. Formulation FMS 5 (HPMC K-100) selected for coating with Eudragit S-100 as it shows significant drug content uniformity and consistent drug release. Eudragit S-100 coated formulations control the drug release in first hrs. at pH 1.2 and 6.8 and shows burst release at pH 7.4 after 7 hrs. This is due to pH dependent nature of eudragit polymer. Compatibility studies revealed that there was no interaction between drug and the polymers. Conclusion: From observations mentioned in the results, it is obvious that the developed salbutamol sulphate enteric coated matrix tablets are suitable for chronotherapeutic drug delivery system.

Objective: The aim of the study was to develop a precise, accurate, and rapid ultraviolet spectrophotometric method for simultaneous estimation of levosulpiride (LEVO) and rabeprazole sodium (RBS) in the binary mixture and to validate the method as per ICH guidelines.Method: Estimation of LEVO and RBS was performed by Q-absorbance method. Analysis was performed using the ratio of absorbance at two selected wavelengths, one at iso-absorptive point and other is the absorbance maxima of any one of the components. Single scan spectrum and the overlain spectrum conclude that absorbance maxima of LEVO and RBS are 228 and 291.8 nm, respectively, with a coinciding iso-absorptive point at 255 nm. Method uses a ratio of absorbance for assay at 255 and the second wavelength is 291.8 nm, λ max for RBS. It is also applicable at 228 nm, as the second wavelength.Results: Linearity of LEVO and RBS was found to be 25-125 and 4-36 μg/ml, respectively. The accuracy of the LEVO and RBS was found 99.26% and 99.51%, respectively and Sandell's sensitivity ranged between 0.0238 and 0.594 µg/cm 2 . Assay of LEVO (75 mg) and RBS (20 mg) in capsule dosage form was found 99.5% and 98.69% w/w, respectively. Conclusions:The developed method for the estimation of LEVO and RBS in binary mixture were found to be simple, accurate, robust, and reproducible. No interference of excipients and the degraded product was found during the estimation. Therefore, the method can be successfully applied for routine quality control analysis.

The scientific way to develop an easy and robust analytical technique for critical analysis is a QbD approach. QbD is a systematic approach to product or method development that begins with predefined objectives and uses science and risk management approaches to achieve product and method understanding and ultimately method control. The aim of the analytical QbD is to achieve quality in measurement. The main objective of this review to explain different steps involved in method development by the QbD approach for analytical method development and describes the implementation of QbD in analytical procedure validation. The advantages of applying QbD principles to analytical technique include discovering and minimizing the source of variability that may lead to poor method robustness and ensuring that the method meets its intended performance need throughout the product and method lifecycle. Keywords: Quality by design (QbD), Risk Analysis, Analytical method validation

There are many problems with the conventional dosage form of various drugs and one of them is dosing frequency in which patients have to take the drug again and again throughout the day which is very difficult mainly for the elder patient. So, to overcome this problem the approach of a novel drug delivery system (NDDS) is used to replace the conventional drug delivery system. NDDS mainly deals with sustained release of drugs which is effective to reduce the dosing frequency. Niosome is one of the best approaches of a novel drug delivery system, in which the drug in solution form is enclosed in vesicle which is made up of non-ionic surfactants. In the case of liposome which is another part of NDDS vesicles is made up of phospholipids. Niosome formulation is a powerful tool to resolve the issue of insolubility and the low bioavailability of drugs. This paper overviews the various methods of preparation of Niosome along with its pharmaceutical applications.