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Background: Pharmacovigilance (PV) deals with the detection, collection, assessment, understanding, and prevention of adverse effects associated with drugs. The objective of PV is to ensure the safety of the medicines and patients by monitoring and reporting all adverse drug reactions (ADRs) associated with prescribed medicine usage. Findings have indicated that about 0.2-24% of hospitalization cases are due to ADRs, of which 3.7% of patients have lethal ADRs. The reasons include the number of prescribed drugs, an increased number of new medicines in the market, an inadequate PV system for ADR monitoring, and a need for more awareness and knowledge about ADR reporting. Severe ADRs lead to enhanced hospital stays, increased treatment costs, risk of death, and many medical and economic consequences. Therefore, ADR reporting at its first instance is essential to avoid further harmful effects of the prescribed drugs. In India, the rate of ADR reporting is less than 1%, whereas worldwide, it is 5% due to a need for more awareness about PV and ADR monitoring among healthcare providers and patients. Aim: The main objective of this review is to highlight the current scenario and possible futuristic ways of ADR reporting methods in rural areas of India. Method: We have searched the literature using PubMed, Google scholar, Indian citation index to retrieve the resources related to ADR monitoring and reporting in India's urban and rural areas. Results: Spontaneous reporting is the most commonly used PV method to report ADRs in India's urban and rural areas. Evidence revealed that no effective ADR reporting mechanisms developed in rural areas causing underreporting of ADR, thus increasing the threat to the rural population. Conclusion: Hence, PV and ADR reporting awareness among healthcare professionals and patients, telecommunication, telemedicine, use of social media and electronic medical records, and artificial intelligence are the potential approaches for prevention, monitoring, and reporting of ADR in rural areas.

The coronavirus disease (COVID-19) has relentlessly spread all over the world even after the advent of vaccines. It demands management, treatment, and prevention as well with utmost safety and effectiveness. It is well researched that herbal medicines or natural products have shown promising outcomes to strengthen immunity with antiviral potential against SARS-COV-2.Our objective is to provide a comprehensive insight into the preventive and therapeutic effects of herbal medicines and products (Ayurvedic) for pre-and post-COVID manifestations.The database used in the text is collected and compiled from Scopus, PubMed, Nature, Elsevier, Web of Science, bioRxiv, medRxiv, American Chemical Society, and clinicaltrials.gov up to January 2022. Articles from non-academic sources such as websites and news were also retrieved. Exploration of the studies was executed to recognize supplementary publications of research studies and systematic reviews. The keywords, such as "SARS-COV-2, coronavirus, COVID-19, herbal drugs, immunity, herbal immunomodulators, infection, herbal antiviral drugs, and WHO recommendation" were thoroughly searched. Chemical structures were drawn using the software Chemdraw Professional 15.0.0.160 (PerkinElmer Informatics, Inc.).A plethora of literature supports that the use of herbal regimens not only strengthen immunity but can also treat SARS-COV-2 infection with minimal side effects. This review summarizes the mechanistic insights into herbal therapy engaging interferons and antibodies to boost the response against SARS-COV-2 infection, several clinical trials, and in silico studies (computational approaches) on selected natural products including, Ashwagandha, Guduchi, Yashtimadhu, Tulsi, etc. as preventive and therapeutic measures against COVID. We have also emphasized the exploitation of herbal medicine-based pharmaceutical products along with perspectives for unseen upcoming alike diseases.According to the current state of art and cutting-edge research on herbal medicines have showed a significant promise as modern COVID tools. Since vaccination cannot be purported as a long-term cure for viral infections, herbal/natural medicines can only be considered a viable alternative to current remedies, as conceived from our collected data to unroot recurring viral infections.

Introduction: Solid lipid nanoparticles (SLNs) are solid core lipid nanocarriers, which can hold both hydrophilic and hydrophobic drugs. They can be made up of biocompatible ingredients and therefore are one of the preferred choices for drug delivery. Surface modifications of SLNs may further provide unique features to them like mucoadhesiveness or targeting capability.Areas covered: In this review, the authors have covered areas from the basic introduction of SLNs to its applications in controlled drug delivery. More specifically, the authors have covered patents disclosed related to the SLNs for the period 2014-2019; however, a summary of patents of 2008-2013 is also included.Expert opinion: SLNs have been explored for development of compositions/formulations with improved therapeutics or cosmetic applications or for nutraceutical applications. Targeted SLNs compositions have been patented as evidenced from the literature; however, not such types of enough SLNs formulations have been claimed for the same.

Background: Nanopharmaceuticals serve as emerging forms of modern medicines, which include nanomedicines, nanosimilars, nanotheranostics, nanodevices, and many more. In the last two decades, a large number of nano-based products have reached the market and are being used clinically. Objectives: Unlike conventional pharmaceutical products, nanopharmaceuticals behave differently both in vitro and in vivo, and therefore, the development of their generic versions needs special attention to replicate the similar drug release pattern leading to an identical therapeutic outcome. Further, drug-device combinations and 3D products are the latest advancements in precision medicine delivery and development. Methods: The regulatory guidelines for these products are being framed at many stages by various regulatory agencies like USFDA/EMA and still are in infancy at the moment if we look at wider perspectives and applications of nanomedicine. Results: For a formulation scientist, it is much needed that well-explained and directive guidelines should be made available before leading to the development of the generic versions of these nano-cargos. Conclusion: Here, in this review, we have summarized the silent features of the regulatory perspectives related to nanotechnology based next generation therapeutics and diagnostics.

Hepatocellular carcinoma (HCC) is a foremost type of cancer problem in which asialoglycoprotein receptors are overexpressed. In this study, asialoglycoprotein receptor–targeted nanoformulation (galactose-conjugated TPGS micelles) loaded with docetaxel (DTX) was developed to achieve its site-specific delivery for HCC therapy. The pharmaceutical characteristics like shape morphology, average particle size and zeta potential, drug entrapment efficiency, and in vitro release kinetics of developed system were evaluated. DTX-loaded galactosylated TPGS (DTX-TPGS-Gal) micelles and TPGS micelles (DTX-TPGS) were having 58.76 ± 1.82% and 54.76 ± 1.42% entrapment of the DTX, respectively. In vitro drug release behavior from micelles was controlled release. Cytotoxicitiy (IC50) of DTX-TPGS-Gal formulation on HepG2 cell lines was significantly (p ≤ 0.01) lower (6.3 ± 0.86 μg/ml) than DTX-TPGS (9.06 ± 0.82 μg/ml) and plain DTX (16.06 ± 0.98 μg/ml) indicating higher efficacy of targeted formulation. Further, in vivo biodistribution studies in animal model showed maximum drug accumulation at target site, i.e., the liver in the case of DTX-TPGS-Gal as compared with non-targeted one. It is concluded from the findings that TPGS-Gal micelles can be utilized for targeted drug delivery of cytotoxic drugs towards HCC with minimized side effects.

Nanotheranostics, an approach of combining both diagnosis and therapy, is one of the latest advances in cancer therapy particularly. Nanocarriers designed and derived from inorganic materials such as like gold nanoparticles, silica nanoparticles, magnetic nanoparticles and carbon nanotubes have been explored for tremendous applications in this area. Similarly, nanoparticles composed of some organic material alone or in combination with inorganic nano-cargos have been developed pre-clinically and possess excellent features desired. Photothermal therapy, MRI, simultaneous imaging and delivery, and combination chemotherapy with a diagnosis are a few of the known methods exploring cancer therapy and detection at organ/tissue/molecular/sub-cellular level. This review comprises an overview of the recent reports meant for nano theranostics purposes. Targeted cancer nanotheranostics have been included for understating tumor micro-environment or cell-specific targeting approach employed. A brief account of various strategies is also included for the readers highlighting the mechanism of cancer therapy.

Background Transdermal drug delivery represents an extremely attractive and innovative route across the skin owing to the possibility for achieving systemic effect of drugs. The present scenario demands a special focus on developing safe medicine with minimized toxic adverse effects related to most of the pharmacologically active agents. Transdermal drug delivery would be a focal paradigm which provides patient convenience, first-pass hepatic metabolism avoidance, local targeting and reduction in toxic effect related to various categories of drugs like, analgesics, antiinflammatory, antibiotics, antiviral, anaesthetic, anticancer etc. Even this route has challenges due to highly organized structure of skin which acts as a main barrier to penetration of drug via the skin. Method Several alternative possible strategies are available which overcome these barriers, including use of penetration enhancer, eletroporation, iontophoresis and various nanotechnologically developed nanocarrier systems. The latest one includes employing liposome, dendrimers, nanoparticles, ethosome, carbon nanotube and many more to avoid associated limitations of conventional formulations. Numerous transdermal products such as Estrasorb, Diractin, VivaGel®, Daytrana®, Aczone, Sileryst® are available in the market having a novel strategy to achieve higher penetration of drugs. This encourages formulation fraternity to develop structurally deformable and stable nanocarriers as an alternative approach for controlled and reliable drug delivery across the skin barrier. Discussion In this review, we will discuss nanocarriers mediated approaches that come-up with the solutions to the different challenges towards transdermal drug delivery, its clinical importance and latest insight to research in it. Conclusion The reports presented in this review confirm the wide application of nanocarriers for transdermal delivery of drug/gene.

Rheumatoid arthritis is a severe autoimmune disorder, related to joints. It is associated with serious cartilage destruction. This causes disability and reduces the excellence of life. Numerous treatments are existed to combat this disease, however, they are not very efficient and possess severe side effects, higher doses, and frequent administration. Therefore, newer therapies are developed to overcome all these limitations. These include different monoclonal antibodies, immunoglobulins, small molecules used for immunotherapy and transgenes for gene therapy. One of the main goals of these new generation therapeutics is to address the underlying distressing biological processes by specifically targeting the causative agents with fewer systemic side effects and greater patient console. It is very fortuitous that loads of progressive investigations are going on in this field and many of them have entered into the successful clinical trial. But till date, a limited molecule has got FDA clearance and entered the market for treating this devastating disease. This review highlights the overview of conventional therapy and advancements in newer therapeutics including immunotherapy and gene therapy for rheumatoid arthritis. Further, different novel techniques for the delivery of these therapeutics of active and passive targeting are also described.

Surface-modified pH-sensitive liposomal system may be useful for intracellular delivery of chemotherapeutics.Achieving site-specific targeting with over-expressed hyaluronic acid (HA) receptors along with using pH sensitive liposome carrier for intracellular drug delivery was the aim of this study.Stealth HA-targeted pH-sensitive liposomes (SL-pH-HA) were developed and evaluated to achieve effective intracellular delivery of doxorubicin (DOX) vis-a-vis enhanced antitumor activity.The in vitro release studies demonstrated that the release of DOX from SL-pH-HA was pH-dependent, i.e. faster at mildly acidic pH ∼5, compared to physiological pH ∼7.4. SLpH-HA was evaluated for their cytotoxicity potential on CD44 receptor expressing MCF-7 cells. The half maximal inhibitory concentration (IC50) of SL-pH-HA and SL-HA were about 1.9 and 2.5 μM, respectively, after 48 h of incubation. The quantitative uptake study revealed higher localization of targeted liposomes in the receptor positive cells, which was further confirmed by fluorescent microscopy. The antitumor efficacy of the DOX-loaded HA-targeted pH-sensitive liposomes was also verified in a tumor xenograft mouse model.DOX was efficiently delivered to the tumor site by active targeting via HA and CD44 receptor interaction. The major side-effect of conventional DOX formulation, i.e. cardiotoxicity was also estimated by measuring serum enzyme levels of LDH and CPK and found to be minimized with developed formulation. Overall, HA targeted pH-sensitive liposomes were significantly more potent than the non-targeted liposomes in cells expressing high levels of CD44.Results strongly implies the promise of such liposomal system as an intracellular drug delivery carrier developed for potential anticancer treatment.

Heparin, a well known drug for anticoagulant therapy and prophylaxis of deep vein thrombosis and coronary syndromes, is also involved in numerous pathological processes such as inflammation, immune cell migration, tumor cell metastasis, smooth muscle cell proliferation etc. Though heparin is a clinically used anticoagulant with minimal side effects and drug interactions, its clinical use is limited due to parenteral administration. Alternatively, noninvasive delivery approaches such as oral, nasal, pulmonary or transdermal route are being explored that may deal with problems associated with parenteral heparin without compromising therapeutic benefits. For the successful noninvasive delivery of such a large drug candidate, the biological and biochemical barriers must be overcome to achieve a clinically acceptable therapeutic advantage. Nanocarriers significantly improve the pharmacokinetics and clinical effectiveness of the loaded therapeutics by either protecting them from unfavorable bioenvironment or modifying their release at the target site. Novel carriers such as liposomes, nanoparticles, dendrimers etc. have been developed to improve the bioavailability of heparin through various routes of delivery. Overall, the present review provides complete insight to the research that has been carried out for heparin delivery through various routes.

The present investigation reports the development of nanoengineered estrogen receptor (ER) targeted pH-sensitive liposome for the site-specific intracellular delivery of doxorubicin (DOX) for breast cancer therapy. Estrone, a bioligand, was anchored on the surface of pH-sensitive liposome for drug targeting to ERs. The estrone-anchored pH-sensitive liposomes (ES-pH-sensitive-SL) showed fusogenic potential at acidic pH (5.5). In vitro cytotoxicity studies carried out on ER-positive MCF-7 breast carcinoma cells revealed that ES-pH-sensitive-SL formulation was more cytotoxic than non-pH-sensitive targeted liposomes (ES-SL). The flow cytometry analysis confirmed significant enhanced uptake (p < 0.05) of ES-pH-sensitive-SL by MCF-7 cells. Intracellular delivery and nuclear localization of the DOX was confirmed by fluorescence microscopy. The mechanism for higher cytotoxicity shown by estrone-anchored pH-sensitive liposomal-DOX was elucidated using reactive oxygen species (ROS) determination. The in vivo biodistribution studies and antitumor activities of formulations were evaluated on tumor bearing female Balb/c mice followed by intravenous administration. The ES-pH-sensitive-SL efficiently suppressed the breast tumor growth in comparison to both ES-SL and free DOX. Serum enzyme activities such as LDH and CPK levels were assayed for the evaluation of DOX induced cardiotoxicity. The ES-pH-sensitive-SL accelerated the intracellular trafficking of encapsulated DOX, thus increasing the therapeutic efficacy. The findings support that estrone-anchored pH-sensitive liposomes could be one of the promising nanocarriers for the targeted intracellular delivery of anticancer agents to breast cancer with reduced systemic side effects.

Unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) are first choices of clinicians among available anticoagulants. Currently, these agents are administered either parenterally or subcutaneously, which reduces patient compliance and acceptability. Oral heparin may serve as an alternative to both parenteral heparin as well as presently available oral anticoagulants such as warfarin. This review focuses mainly upon recent perspectives in the development of heparin as an oral anticoagulant. The possibility of its success with special emphasis to nanotechnological approaches has been elaborated. Important strategies such as the use of penetration enhancers, the development of lipid conjugates of heparin, and the incorporation of heparin in polymeric matrix systems have been discussed. Additionally, introductory information on biological activities, physiochemical aspects, and pharmacokinetic and pharmacodynamic parameters of heparin is summarized. A brief comparison of UFH and LMWH is also included for reader's benefit. Informative discussion on clinical trials with the successes and limitations of oral heparin formulations is also presented. Overall, the present review provides complete insight to the research that has been carried out for the development of heparin as oral anticoagulant.

In clinical practices, solution of dorzolamide hydrochloride (DH) and timolol maléate (TM) is recommended for the treatment of glaucoma. However, low drug-contact time and poor ocular bioavailability of drugs due to drainage of solution, tear turnover and its dilution or lacrimation limits its uses. In addition, systemic absorption of TM may induce undesirable cardiovascular side effects. Chitosan (CS) is a polycationic biodegradable polymer which provides sustained and local delivery of drugs to the ocular sites. Hyaluronic acid (HA) also provides synergistic effect for mucoadhesion in association with chitosan. In the present study, hyaluronic acid modified chitosan nanoparticles (CS-HA-NPs) loaded with TM and DH were developed and characterized. The CS-HA-NPs were evaluated for size, shape, zeta potential, entrapment efficiency, and mucoadhesive strength. The in vitro release study was also performed in PBS pH 7.4. The ocular irritation potential of CS-HA-NPs was estimated using draize test on albino rabbits. A significant reduction in IOP level was obtained using CS-HA-NPs as compared to plain solution of drug and a comparable higher reduction in IOP level was observed as to CS-NPs. These results suggest that HA potentialy enhance the mucoadhesiveness and efficiency of CS-NPs and may be promising carrier for ocular drug delivery.

Controlled drug delivery to eye is one of the most challenging fields of pharmaceutical research. Low drug-contact time and poor ocular bioavailability due to drainage of solution, tear turnover and its dilution or lacrimation are the problems associated with conventional systems. In addition, anatomical barriers and physiological conditions of eye are also important parameters which control designing of drug delivery systems. Nanosized carriers like micro/nano-suspensions, liposome, niosome, dendrimer, nanoparticles, ocular inserts, implants, hydrogels and prodrug approaches have been developed for this purpose. These novel systems offer manifold advantages over conventional systems as they increase the efficiency of drug delivery by improving the release profile and also reduce drug toxicity. Conventional delivery systems get diluted with tear, washed away through the lacrimal gland and usually require administering at regular time intervals whereas nanocarriers release drug at constant rate for a prolonged period of time and thus enhance its absorption and site specific delivery. This review presents an overview of the various aspects of the ocular drug delivery, with special emphasis on nanocarrier based strategies, including structure of eye, its barriers, delivery routes and the challenges/limitations associated with development of novel nanocarriers. The recent progresses in therapy of ocular disease like gene therapy have also been included so that future options should also be considered from the delivery point of view. Recent progress in the delivery of proteins and peptides via ocular route has also been incorporated for reader benefit.

Construction of safe and effective delivery systems for proteins and peptides is demand of current clinical practices. Biodegradable polymers based particulates carriers fulfill much of the requirement in this applicable field. Number of marketed products related to biodegradable polymers encapsulating proteins is increasing. However, it has not achieved its proper place since problems related to the protein processing and stabilization limits the scientific community. In this present review we have summarized various aspects related to the formulation and processing of biodegradable polymerized microparticles/ nanoparticles for delivery of therapeutic proteins and peptides. A brief introduction of biodegradable polymers has been incorporated for readers benefit. In addition, biodegradable polymers based carriers designed for vaccine delivery has been incorporated in detail. Functionalized biodegradable carrier(s) for site specific delivery of proteineous matter has also been discussed.

The pH-sensitive liposomes have been extensively used as an alternative to conventional liposomes in effective intracellular delivery of therapeutics/antigen/DNA/diagnostics to various compartments of the target cell. Such liposomes are destabilized under acidic conditions of the endocytotic pathway as they usually contain pH-sensitive lipid components. Therefore, the encapsulated content is delivered into the intracellular bio-environment through destabilization or its fusion with the endosomal membrane. The therapeutic efficacy of pH-sensitive liposomes enables them as biomaterial with commercial utility especially in cancer treatment. In addition, targeting ligands including antibodies can be anchored on the surface of pH-sensitive liposomes to target specific cell surface receptors/antigen present on tumor cells. These vesicles have also been widely explored for antigen delivery and serve as immunological adjuvant to enhance the immune response to antigens. The present review deals with recent research updates on application of pH-sensitive liposomes in chemotherapy/diagnostics/antigen/gene delivery etc.

The aim of present study was to investigate the potential of mucoadhesive polymer chitosan (CS) and N-trimethyl chitosan (TMC) based nanoparticulate systems for oral bioavailability enhancement of low molecular weight heparin (LMWH). The TMC was synthesized by methylation of chitosan followed by characterization using infrared spectroscopy and (1)H-NMR spectroscopy. The IR and NMR spectra of TMC confirmed the presence of trimethyl groups and estimated the degree of quaternization for TMC about 46%. TMC nanoparticles were then prepared by ionic gelation method. The developed CS-NPs and TMC-NPs were characterized for various parameters including morphology, particle size, zeta potential, entrapment efficiency, in vitro release behavior and storage stability at different temperature and simulated gastrointestinal tract conditions. The fluorescent microscopy study confirmed the higher particle uptake of TMC-NPs by gastrointestinal epithelium in comparison to the CS-NPs. The concentration of LMWH in the systemic circulation followed by oral administration of formulations was estimated using FXa chromogenic assay. A significant increase (p

Publisher Summary This chapter deals with aspects related to proteins and peptide delivery to or through the ocular route for treatment of local and systemic disorders. The main challenge in ocular delivery is to circumvent the protective barriers of the eye so that the therapeutic molecule can penetrate into the bio-milieu quantities sufficient to treat ophthalmic diseases or to exert its pharmacological action. Although conventional drug delivery systems such as solutions, suspensions, gels, ointments, and inserts have been investigated for controlled ocular delivery, they suffer from problems such as poor drainage of instilled solutions, tear turnover, poor corneal permeability, nasolacrimal drainage, systemic absorption, and blurred vision. Advanced drug delivery systems have been developed with the intention of optimizing and controlling delivery of ocular therapeutics to the target sites, either by increasing its penetration across the mucosa or by prolonging the contact time of the carrier with the ocular surface, and have shown promising results. Most of the proteins and peptides that have been delivered to the eye have been for the treatment of local ocular disorders. Although the ocular route is not the preferred route for systemic delivery of proteins due to limitations such as the poor permeability through a membrane of these large, hydrophilic molecules, metabolism (enzymatic degradation), and low capacity for transport, some significant efforts have been made in this area.

The mucosal delivery of vaccines provides the basis for induction of humoral, cellular and mucosal immune responses against infectious diseases. The delivery of antigens to and through mucosal barriers always remains challenging due to adverse physiological conditions (pH and enzymes) and biological barriers created by tight epithelial junctions restricting transportation of macromolecules. Mucoadhesive and biodegradable polymers offer numerous advantages in therapeutic delivery of proteins/antigens particularly through the mucosal route by protecting antigens from degradation, increasing concentration of antigen in the vicinity of mucosal tissue for better absorption, extending their residence time in the body and/or targeting them to sites of antigen uptake. Furthermore, antigen can be delivered more effectively to the antigen presenting cells by anchoring the ligand having affinity on the surface of carrier for the receptors present on the mucosal epithelial cells.The present review covers various polymeric carriers, which allow the possibility of modification and manipulation of their properties, thereby, enhancing the effectiveness of mucosal vaccines. This article reviews the recent literature and patents in the field of vaccine delivery using mucoadhesive polymeric carriers.The reader will gain insights into various natural polymers, synthetic polymers and ligand derived polymeric carrier systems studied to enhance mucosal immunization.Biodegradable polymeric carriers represent a promising approach for mucosal delivery of vaccine.

The localized delivery of fluconazole (FLZ) by conventional therapy is a major impediment in achieving its therapeutic efficacy against skin infections, such as cutaneous candidiasis. Therefore, the present study was aimed to develop FLZ-loaded vesicular construct(s), such as liposomes and niosomes, incorporated into carbopol gel (1%; w/w) for sustained, localized application. The liposomes and niosomes were prepared by the lipid/nonionic surfactant-based dry-film hydration method and were characterized for different parameters. In addition, antifungal activity was carried out on experimentally induced cutaneous candidiasis in immunosuppressed albino rats. The results showed that the size of liposomes and niosomes was found to be 0.348 ± 0.054 and 0.326 ± 0.033 μm with encapsulation efficiency of 31.8 ± 1.36 and 27.6 ± 1.08%, respectively. The skin-retention studies of FLZ from in vitro and in vivo experiments showed significantly higher accumulation of drug in the case of liposomal gel. The in vivo localization studies in viable skin showed that liposomal gel could produce 14.2-fold higher drug accumulation, compared with plain gel, while it was 3.3-fold more in the case of an equivalent-dose application in the form of niosomal gel. The antifungal study also confirmed the maximum therapeutic efficacy of liposomal gel, as the lowest number of cfu/mL was recorded following liposomal FLZ application. The studies signify the potential of liposomal gel for topical delivery of FLZ with increased accumulation of drug in various strata of skin vis-a-vis through sustained release of drug could maintain the localized effect, resulting in an effective treatment of a life-threatening cutaneous fungal infection.

We here report the successful utilization of estrogen receptor (ER) for the delivery of anticancer drug doxorubicin (DOX) encapsulated within pegylated liposome for the treatment of breast cancer. Estrone (ES) was anchored as ligand on to stealth liposome (ES-SL-DOX) for targeting to ERs. In vitro cytotoxicity study was conducted on ER positive and negative breast carcinoma cells. The fluorescent microscopy studies were performed with estrone anchored stealth liposome (ES-SL) loaded with 6-carboxyfluorescein (6-CF). Pharmacokinetic, tissue distribution studies and tumor growth inhibition were carried out followed by intravenous (i.v.) administration of liposomal formulations. ES-SL-DOX demonstrated strongest cytotoxicity to the ER positive cell lines as compared to non-targeted formulations i.e. SL-DOX and plain DOX confirming that ES-SL-DOX was effectively taken up by cells expressing ERs. The half-life (t(1/2)) of SL-DOX and ES-SL-DOX was about 9 and 13 fold higher than that of the free DOX, respectively. Accumulation of ES-SL-DOX in the tumor tissue was 24.27 and 6.04 times higher as compared to free DOX and SL-DOX respectively, after 8 h. ES-SL-DOX at a dose of 5 mg DOX/kg resulted in effective retardation of tumor growth. These findings support that estrogen receptor(s) may be utilized as potential target for chemotherapy of cancers and estrone anchored stealth liposomes could be one of the promising solutions for the delivery of anticancer agent to breast tumors with reduced side-effects.

The aim of the present study was to develop chylomicron mimicking carrier emulsome for oral lymphatic delivery of methotrexate (MTX), an anticancer drug. The compritol 888 ATO (CA) was used as lipid core and soya lecithin (PC) as stabilizer. The optimized emulsome (1:1.2 mole ratio of CA:PC) showed mean particle size of 160.3 ± 10.2 nm and with 72.8 ± 6.5% drug entrapment efficiency. The differential scanning calorimetric studies revealed a depression in endothermic onset for MTX loaded emulsome. The rapid burst release of the drug was observed in simulated gastric fluid (SGF pH 1.2) with significant increase in particle size of emulsome. However in simulated intestinal fluid (SIF, pH 7.4) a slow and consistent release of the drug was obtained over period of 24 h. Storage stability studies were performed at different temperatures (4 ± 1 and 25 ± 1 °C) for 3 months which suggested that EML remain more stable when stored at refrigerated condition. The in vivo studies were carried out on albino rats and response was estimated collecting blood and lymph both. The pharmacokinetic parameters C max , t max and AUC 0→12 h after duodenal administration of optimized emulsomal formulation and plain MTX solution were 7.1 and 2.4 μg/mL, 4 and 1 h, 40.45 and 7.2 h μg/mL respectively. The relative bioavailability of MTX was enhanced nearly 5.7 times with optimized EML formulation when compared to plain MTX solution with higher uptake and longer residence time of MTX molecules in lymphatics. Thus, emulsome could be used as lymphotropic carrier for delivery of bioactive(s) and hence for bioavailability enhancement.

Estrone-appended liposomal formulation of doxorubicin was designed to enhance the capability of clinically used liposomal doxorubicin formulation with the added advantage of delivery of doxorubicin to its destination site, i.e. cancerous cells over-expressing estrogen receptors (ERs). Estrone was conjugated with distearoyl phosphatidylethanolamine (DSPE) using succinic anhydride as a linker and the conjugate was characterized by IR and mass spectroscopies. Estrone-coupled liposomes were prepared with the composition of egg phosphatidylcholine/cholesterol/distearoyl phosphatidylethanolamine-estrone (PC/CHOL/DSPE-ES) at the molar and drug-lipid ratios of 7:3:0.5 and 0.1:1 (w/w), respectively. The average vesicle sizes of the conventional and estrone-appended liposomes were found to be 193 +/- 24 and 207 +/- 28 nm, respectively. The fluorescent microscopy studies were performed with estrone-appended liposomes loaded with 6-carboxyfluorescein (6-CF). Results of in vivo biodistribution studies showed that estrone-appended liposomes were effectively taken up by cells expressing ERs. The drug uptake study showed that accumulation of ligand-appended liposomes in the breast and uterus was 13.9 and 12.7 times higher when compared with plain drug, and 11.05 and 10.3 times higher when compared with conventional liposomes, respectively, after 8 h of tail vein intravenous administration. The findings are seminal for selective targeting of antineoplastic agents to the ER, which are frequently over-expressed on carcinoma of breast and uterine origin, and opens the promising possibilities for non-immunogenic, site-specific delivery of bioactive(s) to these sites.

The maximum therapeutic potentials of pharmacologically active molecules are generally not attained due to their non specific delivery. Ligands associated with drug or delivery system through which it is delivered provide navigation and direction to the carrier system(s) so as to reach and release bioactive(s) at the desired site of action in a optimum therapeutic concentration vis a vis minimizing the undesired side effects associated with non specific delivery. Many ligands employed and implicated in targeted drug delivery have been reportedly found to be mild to strong immunogenic. Hence, their potential utility is considered to be compromised in achieving concept of magic bullet. Therefore endogenous ligand (bio self molecules) based drug/DNA delivery may be a better alternative they being biocomponents so are non-immunogenic and biocompatible per se. Estrogens and their receptors are over expressed in the several pathophysiological conditions including cardiovascular, osteoarthritis and cancer of prostate and ovaries etc. The selective high density of such portal may be utilized for targeting such estrogen receptor rich sites. The several scientific communities from various fields of specialization of science have explored estrogen(s) and their analogs for the purpose of targeting of bioactive(s) either by preparing estrogen-drug conjugates of using estrogens as site-directing ligands attached with various carrier system(s). This review presents an exhaustive account of how hormones especially estrogens and their derivatives could be used for site-specific delivery of bioactive(s), as diagnostic agents and also the future prospects of these bioligands in controlled and targeted clinical pharmacology. Estrogen-drug conjugates and various carrier systems that utilized estrogens as ligands for site-specific delivery have been reviewed and are discussed in detail.

The objective of the study was to develop lipid drug conjugate nanoparticles (LDC-NPs) of anticancer drug methotrexate (MTX) for oral delivery that faces problems of low and variable bioavailability. The MTX loaded LDC-NPs significantly enhanced bioavailability and reduced MTX associated gastrointestinal toxicity even in higher doses recommended for anticancer therapy.