Fabrication of acetazolamide loaded leciplex for intraocular delivery: Optimization by 32 full factorial design, in vitro, ex vivo and in vivo pharmacodynamics.

The complex structure of the eye poses challenges in delivering drugs effectively, which can be circumvented by employing nanotechnologies. The present study aimed to prepareacetazolamide-loadedleciplex (ACZ - LP) using a simple one-step fabrication approach followed byoptimization employing a 32 Full Factorial Design. The ACZ - LP demonstrated high entrapment efficiency (93.25 ± 2.32 %), average diameter was recorded around 171.03 ± 3.32 with monodisperse size distribution and zeta potential of 41.33 ± 2.10 mV. Invitro release and ex vivo permeation studies of prepared formulation demonstrated an initial burst release in 1 h followed by sustained release pattern as compared to plain acetazolamide solution. Moreover, an ex vivo corneal drug retention (27.05 ± 1.20 %) and in vitro mucoadhesive studies with different concentration of mucin indicated strong electrostatic bonding confirming the mucoadhesive characteristics of the formulation. Additionally, the histopathological studies ensured that the formulation was non-irritant and nontoxic while and HET-CAM ensured substantial tolerability of the formulation. The in vivo pharmacodynamic investigation carried out on a rabbit model demonstrated that treatment with ACZ - LP resulted in a significant and prolonged reduction in intraocular pressure as compared to plain acetazolamide solution, acetazolamide oral tablet, and Brinzox®. In summary, the ACZ - LP is anefficient and versatile drug delivery approach which demonstrates significant potential in controlling glaucoma.

Fabrication of architectonic nanosponges for intraocular delivery of Brinzolamide: An insight into QbD driven optimization, in vitro characterization, and pharmacodynamics.

The intricate structure of the eye poses difficulties in drug targeting, which can be surmounted with the help of nanoformulation strategies. With this view, brinzolamide nanosponges (BNS) were prepared using the emulsion solvent evaporation technique and optimized via Box-Behnken statistical design. The optimized BNS were further incorporated into a poloxamer 407 in situ gel (BNS-ISG) and evaluated. The optimized BNS showed spherical morphology, entrapment efficiency of 83.12 ± 1.2 % with particle size of 114 ± 2.32 nm and PDI of 0.11 ± 0.01. The optimized BNS-ISG exhibited a pseudoplastic behavior and depicted a gelling temperature and gelation time of 35 ± 0.5 °C and 10 ± 2 s respectively. In-vitro release and ex- vivo permeation studies of BNS-ISG demonstrated a sustained release pattern as compared to Brinzox®. Additionally, the HET-CAM and in vitro cytotoxicity studies (using SIRC cell line) ensured that the formulation was non-irritant and nontoxic for ophthalmic delivery. The in vivo pharmacodynamic study using rabbit model depicted that BNS-ISG treatment significantly lowers the intra ocular pressure for prolonged period of time when compared with Brinzox®. In conclusion, the BNS-ISG is an efficient and scalable drug delivery system with significant potential as the targeted therapy of posterior segment eye diseases.

Potential biomaterials and experimental animal models for inventing new drug delivery approaches in the neurodegenerative disorder: Multiple sclerosis.

The tight junction of endothelial cells in the central nervous system (CNS) has an ideal characteristic, acting as a biological barrier that can securely regulate the movement of molecules in the brain. Tightly closed astrocyte cell junctions on blood capillaries are the blood-brain barrier (BBB). This biological barrier prohibits the entry of polar drugs, cells, and ions, which protect the brain from harmful toxins. However, delivering any therapeutic agent to the brain in neurodegenerative disorders (i.e., schizophrenia, multiple sclerosis, etc.) is extremely difficult. Active immune responses such as microglia, astrocytes, and lymphocytes cross the BBB and attack the nerve cells, which causes the demyelination of neurons. Therefore, there is a hindrance in transmitting electrical signals properly, resulting in blindness, paralysis, and neuropsychiatric problems. The main objective of this article is to shed light on the performance of biomaterials, which will help researchers to create nanocarriers that can cross the blood-brain barrier and achieve a therapeutic concentration of drugs in the CNS of patients with multiple sclerosis (MS). The present review focuses on the importance of biomaterials with diagnostic and therapeutic efficacy that can help enhance multiple sclerosis therapeutic potential. Currently, the development of MS in animal models is limited by immune responses, which prevent MS induction in healthy animals. Therefore, this article also showcases animal models currently used for treating MS. A future advance in developing a novel effective strategy for treating MS is now a potential area of research.

Nose-to-brain delivery of octreotide acetate in situ gel for pituitary adenoma: Pharmacological and in vitro cytotoxicity studies.

Octreotide acetate (OA), a potent octapeptide, is used in the treatment of pituitary adenoma. An approach has been made in the present research to formulate an OA-loaded intranasal in situ gel (OA-ISG) to target pituitary adenoma. To achieve the objective of the present work, OA-ISG was fabricated using cold method, and further optimization was done by 32 factorial design. The optimized formulation was evaluated for gelation temperature, mucoadhesive strength, and % drug release (8 h), and the results were found to be 30.01 ± 0.4 °C, 40.12 ± 0.5 g, and 98.54 ± 0.45 %, respectively. Brain availability of OA was determined through gamma scintigraphy, wherein Cmax for technetium (99mTC) labeled intranasal OA-ISG (99mTC-OA-ISG) was found to be 1.041 % RA/g, and the findings for 99mTC-OA-Solution (intranasal) and 99mTC-OA-Solution (intravenous) were 0.395 % and 0.164 % RA/g, respectively. Consequently, a 3-10-fold increase in brain OA concentrations was observed upon intranasal administration (OA-ISG) as compared to others. Additionally, drug targeting index (100.13), targeting efficiency (10013 %), and direct transport percentage (2564.1 %) corroborate brain targeting of OA via intranasal route. Further, the cytotoxic potential of OA-ISG was screened on human pituitary tumor (GH3) cell lines using MTT assay. The IC50 value was found to be 9.5 µg/mL for OA-ISG, whereas it was 20.1 µg/mL for OA-Solution, thereby confirming the superior results of OA-ISG as compared to OA-Solution. Hence, the developed intranasal OA-ISG can be further explored for establishing its potential clinical safety, and as effective platform for targeted drug delivery to the brain in pituitary adenoma.

Drug Delivery of Natural Products Through Nanocarriers for Effective Breast Cancer Therapy: A Comprehensive Review of Literature.

Despite recent advances in the diagnosis and treatment of breast cancer (BC), it remains a global health issue affecting millions of women annually. Poor prognosis in BC patients is often linked to drug resistance as well as the lack of effective therapeutic options for metastatic and triple-negative BC. In response to these unmet needs, extensive research efforts have been devoted to exploring the anti-BC potentials of natural products owing to their multi-target mechanisms of action and good safety profiles. Various medicinal plant extracts/essential oils and natural bioactive compounds have demonstrated anti-cancer activities in preclinical BC models. Despite the promising preclinical results, however, the clinical translation of natural products has often been hindered by their poor stability, aqueous solubility and bioavailability. There have been attempts to overcome these limitations, particularly via the use of nano-based drug delivery systems (NDDSs). This review highlights the tumour targeting mechanisms of NDDSs, the advantages and disadvantages of the major classes of NDDSs and their current clinical status in BC treatment. Besides, it also discusses the proposed anti-BC mechanisms and nanoformulations of nine medicinal plants' extracts/essential oils and nine natural bioactive compounds; selected via the screening of various scientific databases, including PubMed, Scopus and Google Scholar, based on the following keywords: "Natural Product AND Nanoparticle AND Breast Cancer". Overall, these nanoformulations exhibit improved anti-cancer efficacy against preclinical BC models, with some demonstrating biocompatibility with normal cell lines and mouse models. Further clinical studies are, however, warranted to ascertain their efficacy and biocompatibility in humans.

Nose-to-brain delivery of amisulpride-loaded lipid-based poloxamer-gellan gum nanoemulgel: In vitro and in vivo pharmacological studies.

Unfavorable side effects of available antipsychotics limit the use of conventional delivery systems, where limited exposure of the drugs to the systemic circulation could reduce the associated risks. The potential of intranasal delivery is gaining interest to treat brain disorders by delivering the drugs directly to the brain circumventing the tight junctions of the blood-brain barrier with limited systemic exposure of the entrapped therapeutic. Therefore, the present research was aimed to fabricate, optimize and investigate the therapeutic efficacy of amisulpride (AMS)-loaded intranasal in situ nanoemulgel (AMS-NG) in the treatment of schizophrenia. In this context, AMS nanoemulsion (AMS-NE) was prepared by employing aqueous-titration method and optimized using Box-Behnken statistical design. The optimized nanoemulsion was subjected to evaluation of globule size, transmittance, zeta potential, and mucoadhesive strength, which were found to be 92.15 nm, 99.57%, -18.22 mV, and 8.90 g, respectively. The AMS-NE was converted to AMS-NG using poloxamer 407 and gellan gum. Following pharmacokinetic evaluation in Wistar rats, the brain Cmax for intranasal AMS-NG was found to be 1.48-folds and 3.39-folds higher when compared to intranasal AMS-NE and intravenous AMS-NE, respectively. Moreover, behavioral investigations of developed formulations were devoid of any extrapyramidal side effects in the experimental model. Finally, outcomes of the in vivo hematological study confirmed that intranasal administration of formulation for 28 days did not alter leukocytes and agranulocytes count. In conclusion, the promising results of the developed and optimized intranasal AMS-NG could provide a novel platform for the effective and safe delivery of AMS in schizophrenic patients.

Antipsychotic Potential and Safety Profile of TPGS-Based Mucoadhesive Aripiprazole Nanoemulsion: Development and Optimization for Nose-To-Brain Delivery.

Delivering therapeutics to the brain using conventional dosage forms is always a challenge, thus the present study was aimed to formulate mucoadhesive nanoemulsion (MNE) of aripiprazole (ARP) for intranasal delivery to transport the drug directly to the brain. Therefore, a TPGS based ARP-MNE was formulated and optimized using the Box-Behnken statistical design. The improved in vitro release profile of the formulation was in agreement to enhanced ex vivo permeation through sheep mucous membranes with a maximum rate of permeation co-efficient (62.87  cm h-1 × 103) and flux (31.43  µg cm-2.h-1). The pharmacokinetic profile following single-dose administration showed the maximum concentration of drug in the brain (Cmax) of 15.19 ± 2.51  µg mL-1 and Tmax of 1 h in animals with ARP-MNE as compared to 10.57 ± 1.88  µg mL-1 and 1 h, and 2.52 ± 0.38  µg mL-1 and 3 h upon intranasal and intravenous administration of ARP-NE, respectively. Further, higher values of % drug targeting efficiency (96.9%) and % drug targeting potential (89.73%) of ARP-MNE through intranasal administration were investigated. The studies in Wistar rats showed no existence of extrapyramidal symptoms through the catalepsy test and forelimb retraction results. No ex vivo ciliotoxicity on nasal mucosa reflects the safety of the components and delivery tool. Further, findings on locomotor activity and hind-limb retraction test in ARP-MNE treated animals established its antipsychotic efficacy. Thus, it can be inferred that the developed ARP-MNE could effectively be explored as brain delivery cargo in the effective treatment of schizophrenia without producing any toxic manifestation.

Nose-to-brain delivery of teriflunomide-loaded lipid-based carbopol-gellan gum nanogel for glioma: Pharmacological and in vitro cytotoxicity studies.

The research work was intended to formulate teriflunomide (TFM) loaded nano lipid-based (TNLC) carbopol-gellan gum in situ gel (TNLCGHG) and to investigate its therapeutic efficacy against glioma, a brain and spine tumor. Nanoformulation was developed using gellan gum and carbopol 974P as gelling and mucoadhesive agents, respectively, Glyceryl di-behenate and Glyceryl mono-linoleate blend as lipids, and Gelucire 44/14: water blend as surfactant system. Globule size, PDI, zeta potential, encapsulation efficiency, mucoadhesive strength, and nasal permeation were found to be 117.80 nm, 0.56, -21.86 mV, 81.16%, 4.80 g, and 904 µg/cm2, respectively. Anticancer efficacy of TFM-loaded nano lipid-based carbopol-gellan gum in situ gel (TNLCGHG) was determined in human U-87MG glioma cell line. IC50 was found 7.0 µg/mL for TNLCGHG, 4.8 µg/mL for pure TFM, and 78.5 µg/mL for TNLC, which approve the superiority of surfactant along with gellan gum as permeation enhancer. Brain Cmax for technetium (99mTC) labeled intranasal (i.n.) 99mTC-TNLCGHG was found 2-folds higher than 99mTC-TNLC (i.n.) and 99mTC-TNLC intravenous (i.v.) because the TNLCGHG formulation contains surfactant with natural gelling polymers, which promisingly improved drug permeability. Finally, this research revealed encouraging outcomes and successfully developed intranasal TNLCGHG nanoformulation as a novel tool for safe delivery of TFM in glioma patients.

Preparation, characterization, and optimization of asenapine maleate mucoadhesive nanoemulsion using Box-Behnken design: In vitro and in vivo studies for brain targeting.

The tight junctions between capillary endothelial cells of the blood-brain barrier (BBB) restricts the entry of therapeutics into the brain. Potential of the intranasal delivery tool has been explored in administering the therapeutics directly to the brain, thus bypassing BBB. The objective of this study was to develop and optimize an intranasal mucoadhesive nanoemulsion (MNE) of asenapine maleate (ASP) in order to enhance the nasomucosal adhesion and direct brain targetability for improved efficacy and safety. Box-Behnken statistical design was used to recognize the crucial formulation variables influencing droplet size, size distribution and surface charge of ASP-NE. ASP-MNE was obtained by incorporating GRAS mucoadhesive polymer, Carbopol 971 in the optimized NE. Optimized ASP-MNE displayed spherical morphology with a droplet size of 21.2 ± 0.15 nm and 0.355 polydispersity index. Improved ex-vivo permeation was observed in ASP-NE and ASP-MNE, compared to the ASP-solution. Finally, the optimized formulation was found to be safe in ex-vivo ciliotoxicity study on sheep nasal mucosa. The single-dose pharmacokinetic study in male Wistar rats revealed a significant increase in concentration of ASP in the brain upon intranasal administration of ASP-MNE, with a maximum of 284.33 ± 5.5 ng/mL. The time required to reach maximum brain concentration (1 h) was reduced compared to intravenous administration of ASP-NE (3 h). Furthermore, it has been established during the course of present study, that the brain targeting capability of ASP via intranasal administration had enhanced drug-targeting efficiency and drug-targeting potential. In the animal behavioral studies, no extrapyramidal symptoms were observed after intranasal administration of ASP-MNE, while good locomotor activity and hind-limb retraction test established its antipsychotic activity in treated animals. Thus, it can be concluded that the developed intranasal ASP-MNE could be used as an effective and safe tool for brain targeting of ASP in the treatment of psychotic disorders.

Formulation and evaluation of letrozole-loaded spray dried liposomes with PEs for topical application.

Letrozole (LET), an aromatase inhibitor widely used as a first-line drug for the estrogen-dependent breast cancer treatment in postmenopausal women. In this study, an attempt has been made to develop LET topical drug delivery which would be a more efficient system to treat elevated blood levels of estrogen found in breast cancer patients. The technique involves, encapsulation of the LET in phospholipids using spray dryer. The LET spray-dried powder (LT-SDP) powder was tested by Fourier transform infrared, X-RD, and differential scanning calorimetry. These studies confirm the entrapment efficiency (EE) of the system. The LT-SDP in the form dispersion was further evaluated. The confocal laser scanning microscopy (CLSM) showed spherical vesicles, the particle size, polydispersity index, and the EE was found to be 284.0 nm, 0.247, and 59.08%, respectively. LT-SDP dispersion was added into a cream base with peppermint and olive oil as natural penetration enhancers. Optimized formulation showed superior skin targeting in in vitro and in vivo studies. Cell proliferation assay and flow cytometry was carried out using human cancer cell line of breast MDA-MB-231 which showed superior anti-proliferative action and enhanced apoptosis activity of LT-SDP cream (43.9%) in comparison. The CLSM micrograph, skin irritation, and histopathology studies showed the penetration ability and inertness of the LT-SDP cream, respectively. In vivo bioavailability studies showed an almost four-fold increase in the plasma concentration (11.3 versus 4.2) while the mean residence time (81.11 versus 64.42 h) and half-life (51.01 versus 39.36 h) were reasonably higher than plain LET cream.

Efavirenz-loaded intranasal microemulsion for crossing blood-CNS interfaces in neuronal-AIDS: pharmacokinetic and in vivo safety evaluation.

Purpose: Development of delivery tool for the existing antiretroviral drugs against the neuronal-AIDS in itself is a big challenge because of blood-brain-barrier (BBB). Aim of present research is to formulate efavirenz (EFV) based mucoadhesive microemulsion (EMME) and investigates its efficiency through intranasal delivery.Methods: The EFV microemulsion (EME) was formulated by aqueous titration method. The formulation was screened for globule size, zeta potential and encapsulation efficiency. Bio-distribution of EFV was performed by gamma scintigraphy. Safety of optimized formulation was demonstrated using biochemical, hematological and histopathological data.Results: Experimental data demonstrate that optimized formulation showed significant size (19.04 nm), zeta potential (-32.2 mV) and entrapment efficiency (98.39%). The results of Cmax value suggested that intranasal (i.n.) 99mTc-EMME is able to improve the brain uptake of EFV around 2 folds more than i.n. 99mTC-EME and intravenous (i.v.) 99mTC-EME administrations. The drug targeting index (DTI= 10), drug targeting efficiency (DTE = 1000%) and direct transport percentage (DTP = 89%) were found highly significant for EMME (i.n.) than EME (i.n.). In vivo safety evaluation studies on experimental animals for biochemical, hematological and histopathological parameters remain unchanged.Conclusions: Hence, the intranasal delivery of EMME can be safe and effective tool in the treatment of neuronal-AIDS.

Lopinavir Loaded Spray Dried Liposomes with Penetration Enhancers for Cytotoxic Activity.

OBJECTIVE: HIV protease inhibitors (HIV-PI) are the drugs utilized for the treatment of HIV. However, their effectiveness is limited due to lack of bioavailability and they need to be coadministered with another drug. In this study single lopinavir (LPV) loaded phospholipid vesicles were prepared by the spray-drying method. The LPV-loaded spray-dried powder (L-SDP) was transformed into vesicles and then entrapped in a cream base with peppermint and olive oil. METHOD: It is an Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) membrane fluidity study that is used to predict oil's effect on skin. The central composite design was used to optimize the L-SDP cream formulation. Ex-vivo drug release, skin deposition study, and cell proliferation assays were carried out using cancer cell lines of breast, lung, and skin melanoma. Analysis of DNA by flow cytometry on human breast cancer cell line MDA-MB-231 was carried out. The fluorescence microscopy, histopathological study, and in-vivo bioavailability studies were performed to measure the penetration and inertness of cream in animals. RESULTS: A membrane fluidity study revealed the effectiveness of oils as penetration enhancers. The L-SDP cream showed comparatively superior (%) drug deposition and permeability . Fluorescence images further confirm the penetration ability of the L-SDP cream which showed promising antiproliferative action on breast and lung cancer cells. The histopathological study demonstrates the inertness of cream while in-vivo bioavailability studies showed the many-fold increase in bioavailability of LPV. CONCLUSIONS: The liposomal drug delivery system of LPV has the potential to expose skin to systemic circulation and is useful for treating cancer.

Nanostructured lipid carriers engineered for intranasal delivery of teriflunomide in multiple sclerosis: optimization and in vivo studies.

BACKGROUND: Multiple sclerosis (MS) is one of the most severe autoimmune disorder of the central nervous system (CNS). OBJECTIVE: The present research work was aimed to formulate and investigate teriflunomide (TFM)-loaded intranasal (i.n.) nanostructured lipid carriers (NLC) for the treatment of multiple sclerosis (MS). METHODS: The TFM-loaded NLC (TFM-NLC) nanoparticles were prepared by melt emulsification ultrasonication method using biodegradable and biocompatible polymers. The Box-Behnken statistical design was applied to optimize the formulation. The optimized NLC formulation was subjected to evaluate for particle size, entrapment efficiency (%), in vitro and ex vivo permeation. The safety and efficacy of optimized formulations were demonstrated using pharmacodynamic, subacute toxicity and hepatotoxicity data. RESULTS: Experimental data demonstrated that optimized NLC formulation (F17) showed significant size (99.82 ± 1.36 nm), zeta potential (-22.29 ± 1.8 mV) and % entrapment efficiency (83.39 ± 1.24%). Alternatively, ex vivo permeation of TFM mucoadhesive NLC (TFM-MNLC) and TFM-NLC was observed 830 ± 7.6 and 651 ± 9.8 µg/cm2, respectively. Whereas, TFM-MNLC shows around 2.0-folds more Jss than the TFM-NLC. Finally, TFM-MNLC (i.n.) formulation produced the rapid remyelination in cuprizone-treated animals and decreases the number of entries in open compartment of EPM when compared with negative control and TFM-NLC (oral) animals. Simultaneously, the nanoformulation did not reflect any gross changes in hepatic biomarkers and subacute toxicity when compared with control. CONCLUSIONS: Hence it can be inferred that the nose-to-brain delivery of TFM-MNLC can be considered as effective and safe delivery for brain disorders.

Agranulocytosis-Protective Olanzapine-Loaded Nanostructured Lipid Carriers Engineered for CNS Delivery: Optimization and Hematological Toxicity Studies.

Potential risk of agranulocytosis is one of the drug-induced adverse effects of the second-generation antipsychotic agents. The present investigation aimed to formulate and investigate olanzapine (OLZ)-loaded nanostructured lipid carriers (OLZ-NLCs) via intranasal (i.n.) route. The NLC was prepared by melt emulsification method and optimized by Box-Behnken design. Mucoadhesive NLC was prepared by using 0.4% Carbopol 974P (OLZ-MNLC (C)) and the combination of 17% poloxamer 407 and 0.3% of HPMC K4M (OLZ-MNLC (P+H)). The particle size, zeta potential, and entrapment efficiency were found to be 88.95 nm ± 1.7 nm, - 22.62 mV ± 1.9 mV, and 88.94% ± 3.9%, respectively. Ex vivo permeation of OLZ-NLC, OLZ-MNLC (P+H), and OLZ-MNLC (C) was found to be 545.12 µg/cm2 ± 12.8 µg/cm2, 940.02 µg/cm2 ± 15.5 µg/cm2, and 820.10 µg/cm2 ± 11.3 µg/cm2, respectively, whereas the OLZ-MNLC (P+H) formulation showed rapid drug permeation than the OLZ-NLC and OLZ-MNLC (C) formulations. The OLZ-MNLC (P+H) formulation was shown to have 13.57- and 27.64-fold more Jss than the OLZ-MNLC (C) and OLZ-NLC formulations. The OLZ nanoformulations showed sustained release of up to 8 h. Finally, the brain Cmax of technetium-99m (99mTc)-OLZ-MNLC (i.n.) and 99mTc-OLZ-NLC (i.v.) was found to be 936 ng and 235 ng, respectively, whereas the Cmax of i.n. administration was increased 3.98-fold more than the Cmax of i.v. administration. The in vivo hematological study of OLZ-MNLC (P+H) confirmed that the i.n. formulation did not reflect any variation in leukocyte, RBC and platelet counts. Hence, it can be concluded that the nose-to-brain delivery of OLZ-MNLC (P+H) can be considered as an effective and safe delivery for CNS disorders.

Formulation and ex vivo-in vivo evaluation of pH-triggered brimonidine tartrate in situ gel for the glaucoma treatment using application of 32 factorial design.

CONTEXT: Short residence time, poor bioavailability and poor permeability are the major problems for conventional eye drops treatment. OBJECTIVE: The aim of this article is to develop, optimize and ex vivo-in vivo investigation of brimonidine tartrate in situ gel as compared to marketed eye drops for the treatment of glaucoma. MATERIALS AND METHODS: The effect of independent variables, namely concentrations of polymers, on various dependent variables like viscosity at physiological pH and in vitro drug release were studied by using 32 factorial design. Further the optimized formulation was characterized for ex vivo and in vivo study. RESULTS AND DISCUSSION: Experimental data demonstrated that optimized in situ gel formulation (F8) showed in vitro-ex vivo sustained release profile with polymer composites carbopol 974P and HPMC K4M. After 5 h of ex vivo transcorneal permeation study, the amount recovered from the corneal surface on the donor chamber 12.40% (124 ug) and the amount collected from the receptor chamber 76.8% (760 ug) of the initial dose 1 mg. The total amount recovered from the permeation experiment was 89.2%. Bioadhesive carbopol 974P and viscosity HPMC K4M composites optimized formulation (F 8) produce greater influence on the duration of drug action and improved intraocular pressure reduction activity as compared to marketed eye drop solution in in vivo study. CONCLUSION: The developed in situ gelling system as a promising ophthalmic formulation to prolong the drug lowering effect on the intraocular pressure.

In vitro and in vivo evaluation of colon cancer targeted epichlorohydrin crosslinked Portulaca-alginate beads.

The aim of this study was to formulate a novel dual crosslinked hydrogel bead using Portulaca mucilage for colon-targeted delivery of 5-fluorouracil (5-FU) and evaluate its safety, specificity and efficacy. The ionotropic gelation technique was employed to prepare the hydrogel beads of Portulaca mucilage. For this, the mucilage was initially crosslinked with alginate and calcium ions. Epichlorohydrin was employed as a crosslinker in the second crosslinking step. The formulation was subjected to in vitro and in vivo studies to evaluate morphology, size, cytotoxicity, and organ distribution. Human HT-29 colon cancer cell-line was used for in vitro assays and in vivo studies were performed in Wistar rats to assess the usefulness and effectiveness of the formulation for colon cancer therapy. Microsphere sizes ranged from 930 to 977µm and possessed a high level of drug encapsulation efficiency (ca. 78% w/w). Compared with 5-FU solution (Tmax = 1.2 h, mean resident time: MRT = 3.3h) the dual crosslinked Portulaca microspheres exhibited sustained drug release after oral administration to rats (Tmax = 16h, MRT = 14h). The relative bioavailability of 5-FU solution and the microspheres were 100 and 93.6% respectively. Tissue distribution studies indicated high concentration of 5-FU in colon. In-vitro anticancer assay demonstrated IC50 value of 11.50 µg/ml against HT-29 colon cancer cell line. The epichlorohydrin cross-linked Portulaca microspheres prepared in this study provided sustained release of 5-FU up to 16h in the colonic region and enhanced the antitumor activity of the neoplastic drug. The formulation is hence an ideal carrier system for colon-targeted drug delivery.

Risk management and statistical multivariate analysis approach for design and optimization of satranidazole nanoparticles.

Rapidly evolving technical and regulatory landscapes of the pharmaceutical product development necessitates risk management with application of multivariate analysis using Process Analytical Technology (PAT) and Quality by Design (QbD). Poorly soluble, high dose drug, Satranidazole was optimally nanoprecipitated (SAT-NP) employing principles of Formulation by Design (FbD). The potential risk factors influencing the critical quality attributes (CQA) of SAT-NP were identified using Ishikawa diagram. Plackett-Burman screening design was adopted to screen the eight critical formulation and process parameters influencing the mean particle size, zeta potential and dissolution efficiency at 30min in pH7.4 dissolution medium. Pareto charts (individual and cumulative) revealed three most critical factors influencing CQA of SAT-NP viz. aqueous stabilizer (Polyvinyl alcohol), release modifier (Eudragit® S 100) and volume of aqueous phase. The levels of these three critical formulation attributes were optimized by FbD within established design space to minimize mean particle size, poly dispersity index, and maximize encapsulation efficiency of SAT-NP. Lenth's and Bayesian analysis along with mathematical modeling of results allowed identification and quantification of critical formulation attributes significantly active on the selected CQAs. The optimized SAT-NP exhibited mean particle size; 216nm, polydispersity index; 0.250, zeta potential; -3.75mV and encapsulation efficiency; 78.3%. The product was lyophilized using mannitol to form readily redispersible powder. X-ray diffraction analysis confirmed the conversion of crystalline SAT to amorphous form. In vitro release of SAT-NP in gradually pH changing media showed <20% release in pH1.2 and pH6.8 in 5h, while, complete release (>95%) in pH7.4 in next 3h, indicative of burst release after a lag time. This investigation demonstrated effective application of risk management and QbD tools in developing site-specific release SAT-NP by nanoprecipitation.

Mechanistic investigation of biopharmaceutic and pharmacokinetic characteristics of surface engineering of satranidazole nanocrystals.

The designing of surface engineered nanocrystals for improved stability and bioavailability is a multivariate process depending on several critical formulation and process variables. The present investigation deals with formulation of stable nanocrystals of poorly soluble satranidazole (SAT) for improving dissolution rate and pharmacokinetic profiling. SAT has low polar surface area, high dose and dosing frequency. Based on goniometric and stability studies of formulations prepared with various stabilizers, a unique combination of Span 20 and HPMC E-5 was selected for detailed investigation. Lyophilization of SAT nanosuspension was explored with nine different cryoprotectants in varying amounts to obtain easily redispersible nanocrystals (SAT-NC). The mean particle size and zeta potential of SAT-NC were found to be 208.8nm and -41.3mV respectively. DSC and XRPD confirmed the crystalline state of SAT. In vitro release studies of SAT-NC showed almost complete dissolution within 20min in water. Extravascular, one compartment pharmacokinetic modeling of in vivo plasma concentration versus time studies in male Wistar rats revealed twofold increase in Cmax, and AUC0-∞. Method of residuals was employed to calculate rate of absorption Ka and lag time. Nanosizing with appropriate stabilizers and programmed processing conditions successfully produced SAT-NC with improved pharmaceutic and pharmacokinetic characteristics.

Biosurfactant produced from Actinomycetes nocardiopsis A17: Characterization and its biological evaluation.

This investigation aims to isolate an Actinomycetes strain producing a biosurfactant from the unexplored region of industrial and coal mine areas. Actinomycetes are selected for this study as their novel chemistry was not exhausted and they have tremendous potential to produce bioactive secondary metabolites. The biosurfactant was characterized and further needed to be utilized for pharmaceutical dosage form. Isolation, purification, screening, and characterization of the Actinomycetes A17 were done followed by its fermentation in optimized conditions. The cell-free supernatant was used for the extraction of the biosurfactant and precipitated by cold acetone. The dried precipitate was purified by TLC and the emulsification index, surface tension and CMC were determined. The isolated strain with preferred results was identified as Actinomycetes nocardiopsis A17 with high foam-forming properties. It gives lipase, amylase, gelatinase, and protease activity. The emulsification index was found to be 93±0.8 with surface tension 66.67 dyne/cm at the lowest concentration and cmc 0.6 µg/ml. These biosurfactants were characterized by Fourier transform infra red (FT-IR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS). Therefore, it can be concluded that the biosurfactant produced by Actinomycetes nocardiopsis sp. strain A17 was found to have satisfactory results with high surface activity and emulsion-forming ability.