Digesh Kumar

Bio: Digesh Kumar is an academic researcher from Manipal University. The author has contributed to research in topics: Supply and demand & Credit crunch. The author has an hindex of 2, co-authored 3 publications receiving 34 citations.

Preparation of Mucoadhesive Microspheres for Nasal Delivery by Spray Drying

Abstract: In this study the suitability of spray drying as a method for the formulation of mucoadhesive microspheres for nasal delivery was evaluated. The microspheres were produced from mucoadhesive polymers including chitosan salt, hydroxypropylmethylcellulose, hydroxypropylcellulose, sodium alginate and contained levocetirizine dihydrochloride as the model drug. The microspheres formed were evaluated for particle size distribution, drug loading, production yield, in vitro release characteristics and suitability for nasal drug delivery in terms of particle size and release properties. The conditions of the spray dryer were optimized for production yield and particle size.

Optimal Preservation Technology Investment, Credit Period and Ordering Policies for Deteriorating Inventory under Credit Period Dependent Quadratic Demand

Abstract: The supplier presents its buyer a credit period to settle the account which attracts more buyers and increases market demand. However, the offer of credit period invites default risk for the supplier. In this paper, we also implement efficient preservation technology for our inventory system of deteriorating items. The demand is considered to be quadratic and is dependent of permissible trade credit. The objective is to maximize the total profit per unit time with respect to optimal investment to be made, credit period and procurement quantity. Numerical example is given to illustrate the theoretical results and concavity of total profit is established. Managerial observations are outlined using sensitivity analysis.

Manufacturing process with disruption under Quadratic Demand for Deteriorating Inventory

Abstract: Each and every supply chain or logistics structure is subject to disruption. This disruption may be due to uncertainty or unintended events like instrument break down, unavailability of raw materials, some crisis, natural calamities or strikes. This article first establishes the production time when there is no disruption and afterwards when system gets disrupted. After disruption in the production, we investigate whether it has been resulted in any amount of shortages or not. To maintain the goodwill of the company, an additional replenishment is suggested if there are any shortages. For disrupted production system, disruption time is calculated. Also in the case of shortages, when to replenish and how much to replenish that is also shown in the article. Moreover, quadratic demand for products is analyzed in the present article. This type of demand initially increases with time up to some extent and then it starts to decrease. In addition, the units in the inventory system are subject to deterioration at a constant rate. Numerical example and related graphical studies are given to validate the results. Effects of variations in inventory parameters on production time are shown for manufacturers to take advantageous decisions.

Nasal Drug Delivery Systems: An Overview

Abstract: Since ancient times, drugs have been administered via the nasal route for therapeutic and recreational purposes. The interest in, and importance, of the systemic effects of drugs administered through the nasal route, have expanded over recent decades. Intra-nasal administration of drugs offers an interesting alternative for achieving systemic therapeutic effects of drugs that are comparable to the parenteral route, which can be inconvenient at times or oral administration, which can result in unacceptably low drug bioavailability. So, it is important to understand the potential and limitations of various nasal drug delivery systems. Therefore, the aim of this review article is to discuss the various pharmaceutical dosage forms that have the potential to be utilised for local or systemic drug administration. It is intuitively expected that this review will help to understand and further to develop suitable intra-nasal formulations to achieve specific therapeutic objectives.

Formulation and evaluation of nasal mucoadhesive microspheres of sumatriptan succinate.

Abstract: The purpose of present research work was to develop mucoadhesive microspheres for nasal delivery with the aim to avoid hepatic first-pass metabolism, improve therapeutic efficacy and enhance residence time. For the treatment of migraine, hydroxypropyl methylcellulose (HPMC) K4M and K15M based microspheres containing sumatriptan succinate (SS) were prepared by spray-drying technique. The microspheres were evaluated with respect to the yield, particle size, incorporation efficiency, swelling property, in vitro mucoadhesion, in vitro drug release, histological study and stability. Microspheres were characterized by differential scanning calorimetry, scanning electron microscopy and X-ray diffraction study. It was found that the particle size, swelling ability and incorporation efficiency of microspheres increases with increasing drug-to-polymer ratio. HPMC-based microspheres show adequate mucoadhesion and do not have any destructive effect on nasal mucosa. On the basis of these results, SS microspheres based on HPMC may be considered as a promising nasal delivery system.

Intranasal drug delivery system- A glimpse to become maestro

Abstract: Intranasal drug delivery – which has been practiced for thousands of years, has been given a new lease of life. It is a useful delivery method for drugs that are active in low doses and show no minimal oral bioavailability such as proteins and peptides. One of the reasons for the low degree of absorption of peptides and proteins via the nasal route is rapid movement away from the absorption site in the nasal cavity due to the Mucociliary Clearance mechanism. The nasal route circumvents hepatic first pass elimination associated with the oral delivery: it is easily accessible and suitable for self-medication. The large surface area of the nasal mucosa affords a rapid onset of therapeutic effect, potential for direct-to-central nervous system delivery, no first-pass metabolism, and non-invasiveness; all of which may maximize patient convenience, comfort, and compliance. IN delivery is non-invasive, essentially painless, does not require sterile preparation, and is easily and readily administered by the patient or a physician, e.g., in an emergency setting. Furthermore, the nasal route may offer improved delivery for “non-Lipinski” drugs.