ABSTRACT
The HIV/AIDS pandemic is an increasing global burden with devastating health-related and socioeconomic effects. The widespread use of antiretroviral therapy has dramatically improved life quality and expectancy of infected individuals. But currently available drug regimens and dosage forms are not good enough to eradicate HIV. Suboptimal adherence, toxicity, drug resistance and viral reservoirs make the lifelong treatment of HIV infection challenging. Along with some other organs, highly vascularized and secured with blood-brain barrier (BBB), brain acts as a great reservoir for the HIV virus. But all the available drug delivery techniques are not capable of bypassing the BBB and deliver anti-HIV drugs to the brain. In this review, all the brain delivery techniques available till date has been reviewed and recent noble ideas for delivering anti-HIV drugs to brain has been discussed.
ABSTRACT
The polyphenolic flavonoid Rutin possesses multiple therapeutic effects out of which the anti-inflammatory potential has been well established in the recent literatures. The oral bioavailability of Rutin is very low necessitating its novel drug delivery approach. Phyto-phospholipid complex (phytosomes) is helpful in enhancing oral bioavailability and transdermal permeation of polyphenols. In the present work, Rutin phytosomes (RN-P) were developed and characterized to establish its feasibility for transdermal application in inflammatory conditions. Phytosomes were prepared in five molar ratios of Rutin (0.5 - 1.0) to Phosphatidylcholine (1.0 - 0.5). All RN-Ps showed aqueous solubility higher than pure Rutin. Partition coefficient results indicated the lipophilic nature of free Rutin as well as all RN-Ps with most satisfactory value found at 3.11 ± 0.08 with F3 formulation. Discrete vesicular structures of RN-Ps observed in TEM study. Results of the FT-IR, DSC and XRD studies confirmed the phyto-phospholipid complex formation. XRD reports revealed the reduction in crystallinity of Rutin when in phytosomes form with F3 found to be the least crystalline. SEM studies confirmed the disappearance of rod shaped crystals of Rutin in phytosome formulations. The ex vivo skin permeation study across excised rat abdominal skin confirmed the higher permeability of RN-Ps (33 ± 1.33 %) over pure Rutin (13 ± 0.87 %). The observations made in the present work suggest that phyto-phospholipid complex of Rutin can increase its skin uptake to treat inflammatory conditions in arthritis, rheumatism, athletic aches and may able to deliver the drug for a long duration avoiding the problems associated with oral administration.
ABSTRACT
Dendrimers are novel synthetic polymeric systems having improved physical and chemical properties due to their unique three dimensional architecture. Dendrimers have a well defined size, shape, molecular weight and monodispersity. These are compatible with drug moieties as well as bioactive molecules like DNA, heparin and other polyanions. The nanoscopic size and recognition abilities make dendrimers as ideal building blocks for self-assembly and self-organization systems. The cavities inside the dendritic structure can be modified to incorporate hydrophobic and hydrophilic drugs. The terminal groups are modified to attach antibodies and bioactive substances for targeting purpose along with providing miscibility, reactivity and solubility. Currently, dendrimers are of great interest for delivering drug molecules via different routes as a nanocarrier. Toxicity problems associated with cationic dendrimers are overcome by PEGylation, which neutralizes the charge on them. Dendrimers possess suitable properties to establish itself as a potential carrier for delivery of therapeutic agents irrespective of certain synthetic and regulatory constraints. This review contains various structural aspects and properties of dendrimers along with their pharmaceutical application as a potential novel drug delivery carrier.
ABSTRACT
The aim of the present investigation is to encapsulate rofecoxib in niosomes and incorporate the prepared niosomes into dermal gel base for sustained therapeutic action. Niosomes were prepared by lipid film hydration technique and were analyzed for size, entrapment efficiency and drug retention capacity. Niosomal vesicles were then incorporated into blank carbopol gel to form niosomal gel. The in vitro permeation study across pig skin was performed using Keshary-Chien glass diffusion cell. The size and entrapment efficiency of the niosomal vesicles increased with gradual increase in HLB value of nonionic surfactants used. Maximum drug entrapment was observed with Span 20 with HLB value of 8.6 and drug leakage from vesicles was less at refrigerated condition than at the room temperature. Higher proportion of cholesterol made the niosomal formulation more stable with high drug retention properties. The niosomal gel showed a prolong drug release behavior compared to plain drug gel. Differential scanning calorimetric study of drug loaded gel and pig skin after permeation study confirmed inertness of carbopol gel base toward rofecoxib and absence of drug metabolism in the skin during permeation study, respectively. The niosomal formulations were successfully prepared by lipid film hydration technique using cholesterol and Span as nonionic surfactant. Presence of cholesterol made niosomes more stable with high drug entrapment efficiency and retention properties. The lower flux value of niosomal gel as compared to plain drug gel across pig skin assured the prolong drug release behavior with sustained action.