Pharmaceutical Nanotechnology - Volume 5, Issue 4, 2017

Background: The respiratory tract as a non-invasive route of drug administration is gaining increasing attention in the present time on achieving both local and the systemic therapeutic effects. Success in achieving pulmonary delivery, requires overcoming barriers including mucociliary clearance and uptake by macrophages. An effective drug delivery system delivers the therapeutically active moieties at the right time and rate to target sites. A major limitation associated with most of the currently available conventional and controlled release drug delivery devices is that not all the drug candidates are well absorbed uniformly locally or systemically. Methods: We searched and reviewed the literature focusing on chitosan and chitosan derivative based nanocarrier systems used in pulmonary drug delivery. We focused on the applications of chitosan in the development of nanoparticles for this purpose. Results: Chitosan, a natural linear bio-polyaminosaccharide is central in the development of novel drug delivery systems (NDDS) including nanoparticles for use in the treatment of various respiratory diseases. It achieves this through its unique properties of biodegradability, biocompatibility, mucoadhesivity and its ability to enhance macromolecule permeation across membranes. It also achieves sustained and targeted effects, primary requirements for an effective pulmonary drug delivery system. This review highlights the applications and importance of chitosan with special emphasis on nanotechnology, employed in the management of respiratory diseases such as asthma, Chronic Obstructive Pulmonary Disease (COPD), lung cancer and pulmonary fibrosis. Conclusion: This review will be of interest to both the biological and formulation scientists as it provides a summary on the utility of chitosan in pulmonary drug delivery systems. At present, there are no patented chitosan based controlled release products available for pulmonary drug delivery and so this area has enormous potential in the field of respiratory science.

Background: Vesicular systems like nanotechnology and liposomes are gaining tremendous attention lately in the field of respiratory diseases. These formulations enhance bioavailability of the drug candidate, which could be achieved through a novel drug delivery mechanism. Moreover, the therapeutic potential achieved through these systems is highly controllable over long durations of time providing better efficacy and patient compliance. Objective: The objective of this paper is to review the recent literature on vesicular drug delivery systems containing curcumin. Methods: We have collated and summarized various recent attempts made to develop different controlled release drug delivery systems containing curcumin which would be of great interest for herbal, formulation and biological scientists. There are several vesicular nanotechnological techniques involving curcumin which have been studied recently, targeting pulmonary diseases. Results: Different vesicular systems containing curcumin are being studied for their therapeutic potential in different respiratory diseases. There has been a renewed interest in formulations containing curcumin recently, primarily owing to the broad spectrum therapeutic potential of this miracle substance. Various types of formulations, containing curcumin, targeting different bodily systems have recently emerged and, nevertheless, the search for newer frontiers with this drug goes on. Conclusion: This mini review, in this direction, tries to highlight the key research interventions employing vesicular systems of drug delivery with curcumin.

Background: Nanotechnology has immense significance in the field of medicine, agriculture, business, public health sector due to wide applicability of the nano products. Basically, nanotechnology is the incorporation of nanoscale structures into larger material components to improve the properties of constructed system. Method: Nanotechnology serves as an alternative drug delivery system to the liposomes drug delivery system as the stability of the product in biological fluids is the main problem associated with the liposomal drug delivery system. In the present review, nanoparticles, their applications, various techniques of preparation of nanoparticles and research update on nano particulate drug delivery system have been discussed. Results: The main complication associated with biodegradable polymer is uncertainty in their absorption pathway in gastrointestinal tract. Sometimes, harmful by-products after metabolism are released. However, the polymeric nanoparticles (synthetic or semi-synthetic) have a defined structure therefore; get absorbed in intact form in gastrointestinal tract. Conclusion: Nano-particulate drug delivery system using natural/synthetic polymer may enhance the therapeutic activity of some anti-cancer drug by increasing the host's immune mechanism and antitumor role through improving the body's immune function. It has been observed that despite the technological challenges, nanoparticulate drug delivery system is the most promising drug delivery system in case of anticancer drugs because polymer based nanostructures enhance the bio-adhesiveness and as well as local accumulation of chemotherapeutic agent.

Background: The effective targeted drug delivery system is significant for future development of medicinal product and healthcare. There are also different types of nanostructures which include solid lipid nanoparticles, liposomes, dendrimers, nanostructured lipid carriers, lipid drug conjugate, liquid crystalline particles, polymeric nanocrystals, polymeric nanoparticles and superparamagnetic nanoparticles which have been considered as advanced carriers in drug delivery system. Method & Discussion: In this regard, nano carriers are bringing revolution in therapeutic delivery of drug as compared to conventional delivery systems by overcoming the limitations of usual methods. Conclusion: The objective of this review is to cover the drug delivery system of various therapeutic drugs and biomolecules by means of polymeric nanoparticles, dendrimers, liposomal nanoparticles and magnetic nanoparticles by describing the methods of formulation development.

Background: Bioavailability is the segment of dose that is bioavailable for its therapeutic effect on the systemic circulation without any change in its characteristics, after administration by either route. It is one of the fundamental pharmacokinetic properties of drugs. It is important because, it defines the amount of drug to be administered for its intended therapeutic effect. If drug is more bioavailable, less amount of it is required to obtain therapeutic effect. However, it is also worth mentioning that most of the newly discovered therapeutic agents have poor solubility and thus low bioavailability. Objectives: In this article, various methods including conventional and advanced, have been reviewed that could be potentially used for the enhancement of bioavailability. Moreover, the benefits and drawbacks of all the strategies are deliberated to comprehend the probable use of each method supported by latest references. Methods: Various strategies have been developed to enhance the solubility and thus bioavailability of numerous drugs, some of which are discussed here. All these strategies involve different approaches to improve the bioavailability including physical adaptation, chemical modification and controlling particle size of the engineered particle. Results: These strategies, particularly the nano-particulate systems, not only improve the bioavailability of drugs but at the same time diminish the possible toxicities of the incorporated drugs. Conclusion: It can be concluded that this would be a new source of information for the readers.

Background: Self-nanoemulsifying drug delivery system (SNEDDS) has immense potential in oral bioavailability enhancement of lipophilic drugs. Objective: This investigation involves the development of thermodynamically stable and dilutable SNEDDS for tolbutamide, for achieving higher water solubility and enhanced dissolution rate which in turn improves its oral bioavailability. Method: Preliminary solubility studies were carried out and pseudo-ternary phase diagrams were plotted for selection of best ratio of surfactant and co-surfactant. The drug loaded SNEDDS were prepared, characterized w.r.t. refractive index, viscocity, globule size, zeta potential, and TEM, and converted into solid self-nanoemulsifying granules (SSNEGs). These were further characterized and their antidiabetic efficacy in male Wistar rats was evaluated. Results: Solubility studies suggested the suitability of oleic acid as lipid phase; Tween 20 and PEG 400 as optimal surfactant and co-surfactant, respectively for formulation of SNEDDS formulations. The optimal SNEDDS formulation having mean globule diameter, viscosity, polydispersity 58.55 ± 0.2 nm, 26.18 ± 0.2 cps, 0.277 respectively, and infinite dilution capability displayed a highly significant increase in dissolution rate within 5 h compared to pure drug suspension. The SSNEGs showed 1.54 fold increase in drug dissolution rate compared to pure drug. Stability studies revealed no significant change in morphology and globule size. Anti-hyperglycemic activity of tolbutamide loaded SSNEGs in rats showed a significant reduction in elevated blood glucose level with absence of ketone and glucose in urine. Conclusion: The present study demonstrates a successful development of SNEDDS formulation with an overall potential of bioavailability enhancement for tolbutamide, a BCS-II drug.

Background: There is a rapidly growing interest in the development of nanoparticle drug delivery mainly for anticancer drugs as it promises to solve several problems associated with anticancer drugs such as poor water solubility, low therapeutic index, nonspecific distribution and higher systemic toxicity, etc. Objective: The objective of the study was to investigate the effect of various critical variables like, concentration of chitosan, concentration of sodium tripolyphosphate (STPP) and volume of STPP on various characteristics of gefitinib loaded nanoparticles. Methods: Thirteen formulations of the polymeric nanoparticles were prepared using various concentrations of chitosan (0.1-1% w/v), STPP (0.2-1.5% w/v) and different volumes of STPP (8-20 ml) by ionic gelation method. Mannitol (5% w/v) was used as cryoprotectant. The prepared nanoparticle formulations were characterized for various parameters like particle size, zeta potential, process yield, encapsulation efficiency, drug content, and in vitro drug release. Results: The nanoparticle formulation NF-1 containing 0.1% w/v of chitosan and 10 ml volume of 0.2% w/v STPP showed best results in terms of particle size (123.8nm), polydispersity index (0.247), zeta potential (+30.4 mV), process yield (68.09%), drug content (74.32%), encapsulation efficiency (70.52%) and released (56.2 %) drug over a period of 24 h. The in vitro drug release analysis showed sustained release of gefitinib from nanoparticles and followed Korsmeyer-Peppas model. Conclusion: The nanoparticle formulation with desired characteristics can be prepared at low concentration of chitosan and STPP along with low volume of STPP. The formulated nanoparticles may prove to be the best option for the treatment of cancer.

Background & Objective: Our research objective was to design, develop, optimize and characterize Granisetron HCl transdermal gel in order to minimize side effects associated with oral delivery. Method: A statistical design was practically applied for further optimization and preparation of transfersomal gel using Box-Behnken methodology at three levels. The selected independent and dependent variables were Lipoid, surfactant and sonication time and encapsulation efficiency, size and flux correspondingly. Result: The optimized formulation (GTV-16) morphology, shape, size, potential, encapsulation capacity and flux (using Franz-diffusion cell assembly via animal skin barricade medium) were determined. Then, GTV-16 incorporated into gel and during evaluation nano-transformal gel has good particle size of 127.7±1.08 nm, better entrapment efficiency of 83.0 ± 3.22 % and flux of 20.0 ± 1.88μgcm-2/h. Conclusion: The results demonstrated that Granisetron Hydrochloride loaded nano-gel was significantly superior with 8.5 fold enhancement in bioavailability as compared with drug solution.

Objective: The aim of this study was to prepare solid lipid microparticles (SLM) with incorporated ofloxacin, suitable for oral delivery. Methods: Ofloxacin-loaded SLM were prepared using stearic acid and chloroform as lipid matrix and Tween-80 as surfactant, by high shear homogenization technique and followed by lyophilization. The physiochemical characterization of SLMs were investigated by scanning electron microscopy, transmission electron microscopy, zeta potential, zone of inhibition, in-vitro study, ex-vivo study and stability study. Results: The result demonstrated that the entrapment efficiency, particle size and zeta potential of microparticles were 86.02%, 203.7nm and -32.68mv, respectively. The in-vitro and ex-vivo studies showed sustained release of drug from formulation. Conclusion: These results indicate that SLM might be a promising delivery system to enhance the pharmacological activity of ofloxacin.