Targeting prostate cancer with docetaxel-loaded peptide 563-conjugated PEtOx-co-PEI30%-b-PCL polymeric micelle nanocarriers.

Prostate cancer is a global disease that negatively affects the quality of life. Although various strategies against prostate cancer have been developed, only a few achieved tumor-specific targeting. Therefore, a special emphasis has been placed on the treatment of cancer using nano-carrier-encapsulated chemotherapeutic agents conjugated with tumor-homing peptides. The targeting strategy coupling the drugs with nanotechnology helps to overcome the most common barriers, such as high toxicity and side effects. Prostate-specific membrane antigen has emerged as a promising target molecule for prostate cancer and shown to be targeted with high affinity by GRFLTGGTGRLLRIS peptide known as peptide 563 (P563). Here, we aimed to assess the in vitro and in vivo targeting efficiency, safety, and efficacy of P563-conjugated, docetaxel (DTX)-loaded polymeric micelle nanoparticles (P563-PEtOx-co-PEI30%-b-PCL-DTX) against prostate cancer. To this end, we analyzed the cytotoxic activity of P563-PEtOx-co-PEI30%-b-PCL and P563-PEtOx-co-PEI30%-b-PCL-DTX by a cell proliferation assay using PNT1A and 22Rv1 cells. We have also determined the targeting selectivity of P563-PEtOx-co-PEI30%-b-PCL-FITC by flow cytometry and assessed the induction of cell death by western blot and TUNEL assays for P563-PEtOx-co-PEI30%-b-PCL-DTX in 22Rv1 cells. To investigate the in vivo efficacy, we administered DTX in the free form or in polymeric micelle nanoparticles to athymic CD-1 nu/nu mice 22Rv1 xenograft models and performed histopathological analyses. Our study showed that targeting prostate cancer with P563-conjugated PEtOx-co-PEI30%-b-PCL polymeric micelles could exert a potent anti-cancer activity with low side effects.

Exploiting ionisable nature of PEtOx-co-PEI to prepare pH sensitive, doxorubicin-loaded micelles.

AIMS: This study was conducted to evaluate block copolymers containing two different poly(ethyleneimine) (PEI) amounts, as new pH-sensitive micellar delivery systems for doxorubicin. METHODS: Micelles were prepared with block copolymers consisting of poly(2-ethyl-2-oxazoline)-co-poly(ethyleneimine) (PEtOx-co-PEI) and poly(ε-caprolactone) (PCL) as hydrophilic and hydrophobic blocks, respectively. Doxorubicin loading, micelle size, pH-dependent drug release, and in vitro cytotoxicity on MCF-7 cells were investigated. RESULTS: The average size of drug-loaded micelles was under 100 nm and drug loading was between 10.7% and 48.3% (w/w). pH-sensitive drug release was more pronounced (84.7% and 68.9% (w/w) of drug was released at pH 5.0 and pH 7.4, respectively) for the micelles of the copolymer with the lowest PEI amount. The cell viability of doxorubicin-loaded micelles which were prepared by the copolymer with the lowest PEI amount was 28-33% at 72 h. CONCLUSIONS: PEtOx-co-PEI-b-PCL micelles of this copolymer were found to be stable and effective pH-sensitive nano-sized carriers for doxorubicin delivery.

Preparation, characterization and pharmacokinetic evaluation of rosuvastatin calcium incorporated cyclodextrin-polyanhydride nanoparticles.

Objective: The aim of the study was to formulate, cyclodextrin (CD)-polyanhydride (PA) nanoparticles (CPNs) with rosuvastatin calcium (RCa) in order to enhance the poor oral bioavailability. Methods: CPNs containing RCa/CD complexes were prepared by a modified solvent displacement method and morphological analyses, particle size (PS), polydispersity index (PDI), zeta potential (ZP), encapsulation efficiency (EE), DSC, FT-IR, XRD, 1H-NMR analyses were performed. In vitro release properties, release kinetics, cytotoxicity, in vitro permeability and pharmacokinetic studies were also studied. The stability of the formulations were evaluated during the storage period of 3 months. Results: The physicochemical studies showed that the RCa/CD complexes were well incorporated into CPNs resulted in nanosized particles (215.22 and 189.13 nm) with homogenous size distribution (PDI: 0.203 and 0.182) with relatively high incorporation capacity (76.11 and 68.18%) for the CPN1 and CPN2 formulations respectively. Sustained release of RCa from CPNs were achieved. The cytotoxicity values showed that the safety of the formulations. According to permeability studies, pure RCa had lowest permeability data (3.08 × 10-7 cm⋅s-1 Papp value) while CPNs gained higher permeability data (1.36 × 10-5 and 1.12 × 10-5 cm⋅s-1 Papp values) for the CPN1 and CPN2 formulations respectively. CPN2 formulation was selected for pharmacokinetic studies and analyses results demonstrated that approximately 8-fold relative oral bioavailability enhancement compared to the pure RCa was achieved. Conclusion: Considering the analyses results of the study, CPNs can be regarded as suitable, safe, functional oral delivery systems for RCa with enhanced oral bioavailability.

Development and evaluation of orally disintegrating tablets comprising taste-masked mirtazapine granules.

INTRODUCTION: Orally disintegrating tablets (ODTs) provide an important treatment option for pediatric, geriatric and psychiatric patients. In our previous study, we have performed the initial studies for the formulation development and characterization of new ODT formulations containing a bitter taste drug, mirtazapine, coated with 6% (w/w) Eudragit® E-100 (first group of formulations, FGF) without taste evaluation. In present study, coating ratio of the drug was increased to 8% (w/w) (second group of formulations, SGF) to examine the effect of increased coating ratio of drug on in vitro characterization of the formulations including in vitro taste masking study. MATERIALS AND METHODS: Coacervation technique using Eudragit® E-100 was employed to obtain taste-masked mirtazapine granules. FGF and SGF were compared to original product (Remeron SolTab, an antidepressant drug which produced by pellet technology) in terms of in vitro permeability, in vitro taste masking efficiency which was performed by dissolution studies in salivary medium and dissolution stability. Also, the other tablet characteristics (such as diameter, thickness) of SGF were examined. RESULTS AND DISCUSSION: The disintegration time of the SGF were found as A1 < A2 < A3 < A5 < A4 (8% Eudragit® E-100), but all of the formulations dissolved under 30 seconds and friability values were less than 1%. In vitro taste masking efficiency studies demonstrated that C2 formulation (in FGF) had the most similar dissolution profile to Remeron SolTab. CONCLUSIONS: According to these findings, B2 or C2 (with citric acid or sodium bicarbonate, respectively, with 6% Eudragit® E-100) formulations could be promising alternatives to Remeron SolTab.

Design and In Vitro Evaluation of Bispecific Complexes and Drug Conjugates of Anticancer Peptide, LyP-1 in Human Breast Cancer.

PURPOSE: LyP-1, a nine-amino-acid tumor homing peptide, selectively binds to its cognate receptor, p32. Overexpression of p32 in certain tumors should allow use of LyP-1 as a targeting agent for the delivery of therapeutic or diagnostic agents. Peptide conjugates are developed for enhanced pre-targeting of MDA-MB-231 breast cancer cells with peptide-antibody bispecific complexes and targeting with multiple-drug/-fluorophore-conjugated nano-polymers. METHODS: LyP-1-anti-DTPA bispecific antibody complexes (LyP-1-bsAbCx) were generated by conjugation of anti-DTPA antibody and LyP-1. LyP-1-doxorubicin (Dox), Dox-DTPA-succinyl-polylysine (Dox-DSPL), Dox-DSPL-LyP-1, DTPA-Dox-poly glutamic acid (D-Dox-PGA) or DTPA-rhodamine conjugated polylysine (DSPL-RITC) were prepared. In vitro therapeutic efficacy and targeting by immunofluorescence in MDA-MB-231 breast cancer cells were assessed with Dox-LyP-1. Immunofluorescence visualization of cancer cells was evaluated after pretargeting with LyP-1-bsAbCx and targeting with DSPL-RITC. RESULTS: Cytotoxicity of Dox-LyP-1 conjugates was significantly greater than free doxorubicin (p < 0.0001). For fluorescent-labeled LyP-1, internalization occurred in 30 min in tumor cells. Fluorescence intensity of two-step targeted cells showed that pretargeting with LyP-1-bsAbC, followed by targeting with DSPL-RITC was greater than non-pretargeted DSPL-RITC (p < 0.05). CONCLUSIONS: Peptide-conjugates are effective targeting agents for MDA-MB-231 breast cancer cells in culture. LyP-1-bsAbCx and Dox-LyP-1 conjugates may allow development of novel targeted cancer therapy and diagnosis.

Dry powders for the inhalation of ciprofloxacin or levofloxacin combined with a mucolytic agent for cystic fibrosis patients.

OBJECTIVE: This study aimed to design and characterize an inhalable dry powder of ciprofloxacin or levofloxacin combined with the mucolytics acetylcysteine and dornase alfa for the management of pulmonary infections in patients with cystic fibrosis. METHODS: Ball milling, homogenization in isopropyl alcohol and spray drying processes were used to prepare dry powders for inhalation. Physico-chemical characteristics of the dry powders were assessed via thermogravimetric analysis, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometry and scanning electron microscopy. The particle size distribution, dissolution rate and permeability across Calu-3 cell monolayers were analyzed. The aerodynamic parameters of dry powders were determined using the Andersen cascade impactor (ACI). RESULTS: After the micronization process, the particle sizes of the raw materials significantly decreased. X-ray and DSC results indicated that although ciprofloxacin showed no changes in its crystal structure, the structure of levofloxacin became amorphous after the micronization process. FT-IR spectra exhibited the characteristic peaks for ciprofloxacin and levofloxacin in all formulations. The dissolution rates of micro-homogenized and spray-dried ciprofloxacin were higher than that of untreated ciprofloxacin. ACI results showed that all formulations had a mass median aerodynamic diameter less than 5 µm; however, levofloxacin microparticles showed higher respirability than ciprofloxacin powders did. The permeability of levofloxacin was higher than those of the ciprofloxacin formulations. CONCLUSION: Together, our study showed that these methods could suitably characterize antibiotic and mucolytic-containing dry powder inhalers.

Lysozyme-loaded lipid-polymer hybrid nanoparticles: preparation, characterization and colloidal stability evaluation.

CONTEXT: Lipid-polymer hybrid nanoparticles (LPNPs) are polymeric nanoparticles enveloped by lipid layers, which have emerged as a potent therapeutic nanocarrier alternative to liposomes and polymeric nanoparticles. OBJECTIVE: The aim of this work was to develop, characterize and evaluate LPNPs to deliver a model protein, lysozyme. MATERIALS AND METHODS: Lysozyme-loaded LPNPs were prepared by using the modified w/o/w double-emulsion-solvent-evaporation method. Poly-ɛ-caprolactone (PCL) was used as polymeric core material and tripalmitin:lechitin mixture was used to form a lipid shell around the LPNPs. LPNPs were evaluated for particle size distribution, zeta potential, morphology, encapsulation efficiency, in vitro drug release, stability and cytotoxicity. RESULTS: The DLS measurement results showed that the particle size of LPNPs ranged from 58.04 ± 1.95 nm to 2009.00 ± 0.52 nm. The AFM and TEM images of LPNPs demonstrate that LPNPs are spherical in shape. The protein-loading capacity of LPNPs ranged from 5.81% to 60.32%, depending on the formulation parameters. LPNPs displayed a biphasic drug release pattern with a burst release within 1 h, followed by sustained release afterward. Colloidal stability results of LPNPs in different media showed that particle size and zeta potential values of particles did not change significantly in all media except of FBS 100% for 120 h. Finally, the results of a cellular uptake study showed that LPNPs were significantly taken up by 83.3% in L929 cells. CONCLUSION: We concluded that the LPNPs prepared with PCL as polymeric core material and tripalmitin:lechitin mixture as lipid shell should be a promising choice for protein delivery.

5-Fluorouracil-loaded PLA/PLGA PEG-PPG-PEG polymeric nanoparticles: formulation, in vitro characterization and cell culture studies.

In this study, 5-FU, a potent anticancer drug, is planned to be delivered via a new and promising drug delivery system, nanoparticles formed with hydrophobic core polymer and triblock copolymers; Poly(DL-lactic acid), Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) copolymer (PLA/PEG-PPG-PEG) and Poly(D,L-lactide-co-glycolide)/Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) copolymer (PLGA/PEG-PPG-PEG) nanoparticles. Particle size range of nanoparticles was found to be between 145 and 198 nm, which would promote the passive targeting of the nanoparticles to tumor cells based on the enhanced permeability and retention (EPR) effect. SEM images revealed all nanoparticles formulations to be spherical and without pores. Zeta potential, yield value and encapsulation efficiencies of 5-FU-loaded nanoparticles were within the range of -11.1 and -13.7 mV, 72.7-87.7% and 83.6-93.9%, respectively. Cumulative release of 5-FU was observed between 90% and 94.4% in all nanoparticle formulations by the end of 72 h, and fitness of release profiles to Higuchi model indicated matrix-controlled diffusion of the 5-FU from polymeric nanoparticles. Cell viability values of the cells treated with 5-FU-loaded nanoparticles were obtained as low as 47% and 52% with tetrazolium dye assay, suggesting that delivery of 5-FU via amphiphilic triblock copolymer nanoparticles would be a promising delivery system because of the EPR effect.

In vitro studies on 5-florouracil-loaded DTPA-PE containing nanosized pegylated liposomes for diagnosis and treatment of tumor.

Theranostic liposomes carry both the therapeutic active ingredients and the contrast agent into one delivery system. Codelivery of imaging contrast agent and chemotherapeutic drugs can provide real-time validation of the targeting strategy, resulting in an another step forward for individual-based therapy. The aim of this study was the incorporation of different drugs used in the diagnosis and treatment of tumors into one delivery system to develop nanosized, polyethylene glycol (PEG)-coated, different charged theranostic liposomes. Different charged liposomes consisting of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or Phospholipon(®) 90G (PL 90G; Phospholipid GmbH, Cologne, Germany), cholesterol, poly(ethylene glycol)2000/phosphatidyl ethanolamine (PEG(2000)-PE), stearylamine (SA) or dicetyl phosphate (DCP), and diethylenetriamine pentaacetate/PE (DTPA-PE) as bilayer ingredients and 5-florouracil (5-FU) as active substance were prepared by the film technique. Characterization, 5-FU in vitro release, cytotoxicity, and physical stability studies were performed. Particle size of all liposomes was 100-150 nm. Difference was not noted between encapsulation efficiency (EE%) of neutral DPPC and PL 90G liposomes containing 5-FU. EE% of charged DPPC liposomes was higher than that of charged PL 90G liposomes. PL 90G containing liposomes had a higher phospholipid amount than the same formulation of DPPC liposomes. DPPC containing different charged liposomes were selected for cytotoxicity studies. Different charged DPPC liposomes had the same antitumoral activity with the free 5-FU solution on MCF-7 cell lines. Liposome dispersions were more stable from the point of particle-size change and 5-FU leakage during storage at refrigerated temperature. The results of this study are very encouraging for the development of theranostic liposome formulations as a targeted delivery system for drugs, such as 5-FU, used both in therapy and imaging.

Preparation and characterization of metformin hydrochloride loaded-Eudragit®RSPO and Eudragit®RSPO/PLGA nanoparticles.

The aim of the present study was to develop and characterize metformin HCl-loaded nanoparticle formulations. Nanoparticles were prepared by the nanoprecipitation method using both a single polymer (Eudragit(®)RSPO) and a polymer mixture (Eudragit/PLGA). The mean particle size ranged from 268.8 to 288 nm and the nanoparticle surface was positively charged (9.72 to 10.1 mV). The highest encapsulation efficiency was observed when Eudragit®RSPO was used. All formulations showed highly reproducible drug release profiles and the in vitro drug release in phosphate buffer (pH = 6.8) ranged from 92 to 100% in 12 h. These results suggest that Eudragit(®)RSPO or Eudragit/PLGA nanoparticles might represent a promising sustained-release oral formulation for metformin HCl, reducing the necessity of repeated administrations of high doses to maintain effective plasma concentrations, and thus, increasing patient compliance and reducing the incidence of side-effects.

Preparation and characterization of nimesulide containing nanocrystal formulations.

The aim of this study was to develop and characterize nanocrystal formulation containing nimesulide. Physical mixture of drug and excipient (nimesulide:pluronic F127, 1:0.5) was also prepared to compare the efficiency of formulations. The physicochemical characteristics of the formulations were determined by means of Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), and X-ray diffractometry. Particle size, saturation solubilities as a function of pH, and permeability across Caco-2 monolayers were determined for nimesulide in powder, physical mixture, and nanocrystal formulations. In FT-IR analysis, the characteristic peaks that belong to nimesulide were seen in all formulations. X-ray diffractograms displayed that crystalline structure of nimesulide was conserved in the nanocrystal formulation. The interaction between nimesulide and pluronic F127 was demonstrated by DSC analysis. In all conditions, the average particle size of the nanocrystal formulations decreased significantly (p < 0.05) as compared with nimesulide and physical mixture. The solubility of nimesulide in nanocrystal formulation was higher than those of nimesulide in powder and physical mixture. Permeability studies revealed that nimesulide is a highly permeable compound whether in powder form or in physical mixture and nanocrystal formulation. All these results clearly demonstrate that aqueous solubility of poorly water-soluble compounds can be improved by preparing nanocrystal formulations.

Salmon calcitonin-loaded Eudragit® and Eudragit®-PLGA nanoparticles: in vitro and in vivo evaluation.

The main objective of this study was to prepare salmon calcitonin (sCT)-loaded Eudragit®RSPO, Eudragit®L100 and Eudragit®-poly(lactic-co-glycolic acid) blend nanoparticles for in vitro and in vivo evaluation as an oral drug delivery system. The prepared nanoparticles ranged in size from 179.7 to 308.9 nm with a polydispersity index between 0.051 and 2.75, and had surface charges ~ -11 to +6 mV. Efficient sCT encapsulation and release was observed with all the nanoparticle formulations. The polymer type was an important factor that influenced the release characteristics and the in vivo hypocalcemic effect. Nanoparticle formulations were also prepared with sodium taurodeoxycholate (NaTDC) and characterized. No statistically significant difference was noted between the hypocalcemic effect of any of the nanoparticle formulations with and without NaTDC (p > 0.05). The use of Eudragit®RSPO nanoparticles appears to be a potential approach for the oral delivery of sCT.

Cell culture and pharmacokinetic evaluation of a solid dosage formulation containing a water-insoluble orphan drug manufactured by FDM-3DP technology.

The in-vitro cytotoxicity, in-vitro permeability and in-vivo pharmacokinetics of a BCS Class-II drug - rufinamide - in a 3DP tablet formulation were evaluated. The cytotoxicity of the 3DP tablet formulation was evaluated with an MTT test; in-vitro permeability was evaluated with a Caco-2 cell culture study; and in-vivo pharmacokinetics were evaluated in Wistar albino male rats. The pharmacokinetic studies were performed following a two-sequence and single-period design approach. The highest Caco-2 permeability was obtained with the 3DP tablet formulation; and the highest cell viability was achieved with the 3DP tablet in both the Hep G2 and Caco-2 cell lines. In the in-vivo pharmacokinetic study, AUC and Cmax values were higher in the 3DP tablet formulation than in the Inovelon® film tablet at a 40 mg/kg dose. Thanks to the increased solubility of the active substance, higher in-vitro permeability and in-vivo absorption were achieved with the 3DP tablet formulation, and with lower cytotoxicity. Based on these promising findings, the 3DP tablet formulation can be considered an effective lower-dose treatment than commercial preparations.

The Nanosuspension Formulations of Daidzein: Preparation and In Vitro Characterization

Objectives: Daidzein (DZ), a water-insoluble isoflavone, has many beneficial effects (anti-inflammatory, antioxidant, and anticancer effects, etc.) on human health. DZ has a very low oral bioavailability related to its physicochemical properties (low solubility, intense metabolism of DZ in the intestine and liver). This study aimed to prepare and in vitro characterize the nanosuspension formulations of DZ to improve the poor solubility and efficacy of DZ. Materials and Methods: DZ nanosuspension formulations were prepared with media milling technique using zirconium oxide beads as milling media. Pluronic F127 and polyvinylpyrrolidone (PVP) K30 (formulation A; F-A) and sodium dodecyl sulfate (SDS) (SDS + pluronic F127 + PVP K30; formulation B; F-B) were used as stabilizers. The nanosuspension formulations were evaluated for morphological properties, particle sizes, zeta potential, DZ content, saturation solubility, dissolution, and their cytotoxic effects on RG2 glioblastoma tumor cells. Results: F-A and F-B formulations were nanosized (in the range of about 181-235 nm) and had negative zeta potential values before and after lyophilization. The DZ content of F-A and F-B formulations were found to be 93.68±0.78% and 89.75±0.49%, respectively. Fourier transform infrared spectroscopy analysis showed that there was no significant interaction between DZ and the excipients. Differential scanning calorimetry and X-ray diffraction analyses confirmed no change in the crystal structure of DZ in F-A and F-B formulations. Conclusion: In this study, the nanosuspension formulations were successfully prepared and characterized in vitro. Nanosuspension formulations increased the saturation solubility, dissolution rate, and cytotoxic effect of DZ.

Evaluation of drug-excipient interaction in the formulation of celecoxib tablets.

In the present study, the possible interactions between celecoxib and some excipients (colloidal silicon dioxide (Aerosil), microcrystalline cellulose (Avicel PH 102), lactose anhydrous, magnesium stearate, cross-povidone and talc) were evaluated by examining the pure drug or drug-excipient powder mixtures which were stored under different conditions (25 +/- 2 degrees C, 60% RH +/- 5% RH or 40 + 2 degrees C, 75% RH +/- 5% RH) and different period (30 or 60 days) using DSC, FT-IR and HPLC. In order to investigate the possibility of celecoxib-excipient interaction in aqueous medium, dispersions of the pure drug or drug in physical powder mixture (1:1 w/w) in water (1%, w/v) were also prepared and evaluated by FT-IR and HPLC at day 0 and day 7 (40 +/- 2 degrees C). The interaction between celecoxib and magnesium stearate or colloidal silicon dioxide were determined in the aqueous dispersions by FT-IR. Different tablet formulations with or without excipients tested were prepared, and assessed for drug dissolution and permeability.

Development and characterization of pullulan-based orally disintegrating films containing amlodipine besylate.

The aim of this study was to prepare pullulan-based orally disintegrating films (ODFs) containing amlodipine besylate, an anti-hypertensive drug, by the solvent casting method. For this purpose, nine different ODF formulations (F1-F9) were prepared by using different plasticizers (glycerol, sorbitol, propylene glycol) and different superdisintegrants (croscarmellose sodium, sodium starch glycolate, crospovidone). FD&C Green and aspartame were used as coloring agent and sweetener, respectively. According to the results of preformulation studies, the optimum ODF (F9) was determined and various characterization studies such as uniformity of mass, film thickness, surface pH of films, and mechanical properties (such as elongation at break, tensile strength, Young's modulus, and folding endurance), moisture content, disintegration time, uniformity of content and dissolution test, X-ray, DSC, SEM and short term stability analysis were performed on this formulation. Cytotoxicity and permeability studies for the F9 formulation were performed on the human epithelial colorectal adenocarcinoma (Caco-2) cell line. The formulation F9 had appropriate morphological and mechanical properties and disintegrated within 51.3 s according to the petri dish method, and 28.8 s according to the drop method. Dissolution studies revealed that 78.1 % of amlodipine besylate was dissolved in 20 min from F9 formulation. Cell culture studies showed that the formulation had no significant toxic effect on the Caco-2 cells. Also, there was no significant difference between the Caco-2 permeabilities of amlodipine besylate powder and amlodipine besylate ODFs. As a result of all these studies, we suggest to use the pullulan based amlodipine besylate ODFs to enhance ease of administration and patient compliance.

Formulation and In Vitro Evaluation of Telmisartan Nanoparticles Prepared by Emulsion-Solvent Evaporation Technique.

OBJECTIVES: Telmisartan (TLM) is an antihypertensive drug that has been shown to have antiproliferative effects on cancer cells. It has low solubility and suboptimal oral bioavailability. To investigate the potential anticancer effect of TLM on breast cancer cells, poly (D, L-lactide) (PLA) nanoparticles were formulated with the benefit of improving its solubility. MATERIALS AND METHODS: TLM-loaded PLA nanoparticles were prepared by emulsion solvent evaporation. The effects of sonication time and polymer:drug ratio on nanoparticle size and drug encapsulation were investigated. TLM-loaded nanoparticles were tested against MCF-7 and MD-AMB-231 breast cancer cell lines for antiproliferative effects. RESULTS: Nanoparticles with mean particle size 272 nm and 79% encapsulation efficiency were obtained. Sustained release TLM nanoparticles (40% in 24 h) decreased cell viability to 45% for MCF-7 cells at 72 h, even at the lowest TLM concentration, indicating better anticancer efficiency than TLM solution. CONCLUSION: TLM nanoparticles could be potential anticancer agents for breast cancer and deserve further studies.

Design of ocular drug delivery platforms and in vitro - in vivo evaluation of riboflavin to the cornea by non-interventional (epi-on) technique for keratoconus treatment.

AIM: Keratoconus is a common and progressive eye disease characterized by thinning and tapering of the cornea. This degenerative eye disease is currently treated in the clinic with an interventional technique ("epi-off") that can cause serious side effects as a result of the surgical procedure. The aim of this project is to design innovative formulations for the development of a riboflavin-containing medicinal product to develop a non-invasive ("epi-on") keratoconus treatment as an alternative to current treatment modalities. METHODS: Nanostructured lipid carriers (NLCs) were successfully loaded with either riboflavin base of riboflavin-5-phosphate sodium and designed with either Stearylamine (positive charge) or Trancutol P (permeation enhancer). In vitro characterization studies, cytotoxicity and permeability studies were performed. Selected formulations and commercial preparations were applied and compared in ex-vivo corneal drug accumulation and transition studies. Furthermore, in vivo studies were performed to assess drug accumulation in the rat cornea and the corneal stability after NLC treatment was investigated via a biomechanical study on isolated rabbit corneas. RESULTS: Both in vitro and ex-vivo as well as in vivo data showed that from the prepared NLC formulations, the most effective formulation was riboflavin-5-phosphate sodium containing NLC with Transcutol P as permeation enhancer. It possessed the highest drug loading content, low accumulation in the cornea but high permeability through the cornea as well as the highest functional performance in corneal crosslinking. CONCLUSION: Topical application of riboflavin-5-phosphate sodium loaded NLC systems designed with permeation enhancer Transcutol P may act as a potential alternative for non-invasive keratoconus treatments.

Development of an Anti-Inflammatory Drug-Incorporated Biomimetic Scaffold for Corneal Tissue Engineering.

Purpose: The aim of this study was to design naproxen sodium (NS)-containing, biomimetic, porous poly(lactide-co-glycolide) (PLGA) scaffolds for regeneration of damaged corneal epithelium. Methods: NS-incorporated PLGA scaffolds were prepared using the emulsion freeze-drying method and then coated with collagen or poly-l-lysine. Porosity measurements of the scaffolds were performed by the gas adsorption/desorption method and the scaffolds demonstrated highly porous, open-cellular pore structures with pore sizes from 150 to 200 µm. Results: The drug loading efficiency of scaffolds was found to be higher than 84%, and about 90%-98% of NS was released at the end of 7 days with a fast drug release rate at the initial period of time and then in a slow and sustained manner. The corneal epithelial cells were isolated from New Zealand white rabbits. The obtained cells were seeded onto scaffolds and continued to increase during the time period of the study, indicating that the scaffolds might promote corneal epithelial cell proliferation without causing toxic effects for at least 10 days. Conclusions: The NS-loaded PLGA scaffolds exhibited a combination of controlled drug release and biomimetic properties that might be attractive for use in treatment of corneal damage both for controlled release and biomedical applications.

Combination of Paclitaxel and R-flurbiprofen loaded PLGA nanoparticles suppresses glioblastoma growth on systemic administration.

Malignant gliomas are highly lethal. Delivering chemotherapeutic drugs to the brain in sufficient concentration is the major limitation in their treatment due to the blood-brain barrier (BBB). Drug delivery systems may overcome this limitation and can improve the transportation through the BBB. Paclitaxel is an antimicrotubule agent with effective anticancer activity but limited BBB permeability. R-Flurbiprofen is a nonsteroidal antienflammatory drug and has potential anticancer activity. Accordingly, we designed an approach combining R-flurbiprofen and paclitaxel and positively-charged chitosan-modified poly-lactide-co-glycolic acid (PLGA) nanoparticles (NPs) and to transport them to glioma tissue. NPs were characterized and, cytotoxicity and cellular uptake studies were carried out in vitro. The in vivo efficacy of the combination and formulations were evaluated using a rat RG2 glioma tumor model. Polyethylene glycol (PEG) modified and chitosan-coated PLGA NPs demonstrated efficient cytotoxic activity and were internalized by the tumor cells in RG2 cell culture. In vivo studies showed that the chitosan-coated and PEGylated NPs loaded with paclitaxel and R-flurbiprofen exhibited significantly higher therapeutic activity against glioma. In conclusion, PLGA NPs can efficiently carry their payloads to glioma tissue and the combined use of anticancer and anti-inflammatory drugs may exert additional anti-tumor activity.