Self-Assembled Peptide-Based Biocomposites for Near-Infrared Light Triggered Drug Release to Tumor Cells.

The application of α-mangostin (AMG) in breast cancer research has wide intentions. Chitosan-based nanoparticles (CSNPs) have attractive prospects for developing anticancer drugs, especially in their high flexibility for modification to enhance their anticancer action. This research aimed to study the impact of depolymerized chitosan (CS) on the cytotoxicity enhancement of AMG in MCF-7 breast cancer cells. CSNPs effectivity depends on size, shape, crystallinity degree, and charge surface. Modifying CS molecular weight (MW) is expected to influence CSNPs’ characteristics, impacting size, shape, crystallinity degree, and charge surface. CSNPs are developed using the method of ionic gelation with sodium tripolyphosphate (TPP) as a crosslinker and spray pyrolysis procedure. Nanoparticles’ (NPs) sizes vary from 205.3 ± 81 nm to 450.9 ± 235 nm, ZP charges range from +10.56 mV to +51.56 mV, and entrapment efficiency from 85.35% to 90.45%. The morphology of NPs are all the same spherical forms. In vitro release studies confirmed that AMG–Chitosan–High Molecular Weight (AMG–CS–HMW) and AMG–Chitosan–Low Molecular Weight (AMG–CS–LMW) had a sustained-release system profile. MW has a great influence on surface, drug release, and cytotoxicity enhancement of AMG in CSNPs to MCF-7 cancer cells. The preparations AMG–CS–HMW and AMG–CS–LMW NPs considerably enhanced the cytotoxicity of MCF-7 cells with IC50 values of 5.90 ± 0.08 µg/mL and 4.90 ± 0.16 µg/mL, respectively, as compared with the non-nano particle formulation with an IC50 of 8.47 ± 0.29 µg/mL. These findings suggest that CSNPs can enhance the physicochemical characteristics and cytotoxicity of AMG in breast cancer treatment.

Metformin HCl microspheres were prepared with the aim of increasing its bioavailability and decreasing gastrointestinal side effects by means of sustained action. Eudragit RSPO and Eudragit RLPO, polymers of different permeability characteristics were used to prepare different microspheres. Emulsification solvent evaporation technique using acetone as the internal phase and liquid paraffin as the external phase was the method of choice. Six formulations were prepared using two polymers. The effect of drug loading and polymeric property on the surface morphology, entrapment efficiency, particle size and release characteristics of the microspheres were examined. FTIR and DSC studies established compatibility of the drug with the polymers. SEM studies clearly revealed the effect of drug loading and polymeric nature on the surface morphology of the microspheres. Entrapment efficiencies were within 77.09-97.11% and particle size of all the batches were in the acceptable range. Release data were treated with different mathematical kinetic models. The drug release profile showed that Eudragit RSPO and Eudragit RLPO have opposite effect on drug release. On the other hand, increase in drug loading results in increased drug release. Kinetic modeling of in vitro dissolution profiles revealed that the drug release mechanism varies from diffusion controlled to anomalous type. Dhaka Univ. J. Pharm. Sci. 12(2): 131-141, 2013 (December) DOI: http://dx.doi.org/10.3329/dujps.v12i2.17611

Background: Intra-lysosomal targeting has been investigated for the treatment of cancer but details of the cytotoxicity pathways remain unclear. A high molecular weight gelatin - doxorubicin conjugate (GDox) has been synthesized to target acidic lysosomes for intra-lysosomal drug release. The purpose of this investigation was to explore GDox feasibility for drug delivery and to make a preliminary determination of a cytotoxic pathway. Methods: GDox was synthesized in formamide using the carbodiimide, EDC. Drug load was determined spectroscopically, drug release at pH 4.8 was determined by HPLC, and molecular weight and its reduction in FBS was determined by HPSEC. Cellular localization was determined for free Dox and GDox at 10 µM or its equivalent Dox concentration using fluorescence microscopy with appropriate subcellular stains. Three to four independent trials (n=3-4) were examined with 200 to 700 cells per time point. Cytotoxicity was determing by the MTT procedure (n=3). Viabilities, growth inhibition profiles and their IC50 values were calculated with GraphPad Prism 7. The nucleus content of free Dox or Dox released from GDox after incubation was determined by UHPLC using fluorescent detection (n=3-4). Results: A typical GDox contained 5.6% w/w Dox, had a molecular weight of ~ 160 kDa, and released 58+2.3% Dox at pH 4.8 representing lysosomal pH. After incubation in FBS at 37°C for 24 hr the low molecular weight species increased a relatively small 16%. Fluorescent images with LysoTracker Green confirmed GDox localization to the lysosome which was detectable by 2 hr but substantial in swollen lysosomes by 24 and 48 hrs. No released Dox was observed in the nucleus, but a slight red nucleus haze at later times suggested this possibility. Cell debri from GDox was not observed from free Dox. As expected, free Dox rapidly accumulated in the nucleus by 2 hr. Viability determinations at 0.1, 1, and 10 µM for 2 to 48 hr showed no effect from either agent before 24 hr. By 48 hr at 10 µM, the viability of Dox (30+12%) and GDox (36+13%) were indistinguishable (p=0.68). However, by 72 hr, IC50 values varied 10-fold at 0.094 and 0.96 µM, respectively. The nucleus drug content after incubation at 10 µM for 2 to 48 hr was 0.27+0.07 to 1.39+0.6 µg/106 cells (p&lt0.01) for free Dox, and 0.014+0.01 to 0.11+0.06 µg/106 cells (p&lt0.01) for released Dox. Conclusions: Taken together these results suggest good feasibility of GDox lysosomal targeting and Dox release in MCF7 breast cancer cells. Of note, after 48 hr incubation GDox produced the same cytotoxicity as the free drug but with 13-fold less Dox in the nucleus. This striking nucleus difference and the substantial lysosomal GDox content suggest a lysosomal pathway of GDox cytotoxicity in addition to a nuclear pathway. Support: NIH/NCI R15CA135421 and the Agnes Varis Trust for Women's Leadership and Health. Citation Format: Mohammed Alvi, Bayan Eshmawi, Rachel Nicoletto, Hyun Kate Kim, Christopher Cammarata, Clyde Ofner. Lysosomal targeting from a gelatin-doxorubicin conjugate produces evidence of both nuclear and lysosomal cytotoxcity pathways in mcf-7 breast cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4663.

Drug release studies from lipid nanoparticles in physiological media by a new DSC method

The main objective of present investigation was to design the colorectal microspheres of Capecitabine by using inexpensive natural polysaccharide based polymers. The pectin microspheres were prepared by single emulsification technique using calcium chloride as crosslinking agent. Pectin loaded microspheres were coated with ethyl cellulose by solvent evaporation method. The prepared microspheres were characterized by entrapment efficiency, particle size, in-vitro drug release, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Differential scanning calorimetry (DSC). The in-vitro drug release behaviour of ethyl cellulose coated pectin microspheres done in varying pH conditions up to 12 hr. Optimized uncoated batch of pectin based capecitabine microspheres showed optimum particle size with good drug encapsulation efficiency and spherical in nature. All the formulations showed less than 20 % drug release in acidic environment. Ethyl cellulose coated microspheres mininised initial burst effect and showed drug release in the range of 85.33 to 95.55% at the end of 12h. As concentration of ethyl cellulose was increased drug release was found to be retarded well. From above results it can be concluded that capecitabine loaded ethyl cellulose coated pectin based microspheres may be the best alternative to conventional tablets to treat the colon cancer.

Introduction: Functionalizing folic acid with a surfactant can enhance drug concentration at cancer sites by forming an outer layer on solid lipid nanoparticles. The formulation development and optimization employed Response Surface Methodology (RSM) based on a Central Composite Design, enabling quantitative evaluation of the effects of independent variables and their interactions on the response parameters. Methods: Poloxamer P 188 was conjugated with folic acid using 1,1-carbonyldimidazole. Folic Acid-Dasatinib Solid Lipid Nanoparticles (FA-DAS-SLN) were prepared using the hot homogenization and sonication method. The formulation was optimized through a central composite design, and the process was optimized using the OFAT approach. Evaluation criteria included particle size, PDI, % entrapment efficiency, surface morphology, and in-vitro drug release studied at pH 5.5 and 7.4. Results & Discussion: Functionalization of folic acid with Poloxamer P 188 was confirmed by FTIR, and the optimized formulation achieved 83.38 ± 0.14% entrapment efficiency, a particle size of 12.06 ± 2.24 nm, and sustained in-vitro release over 72 hours. Greater drug release at pH 5.5 than at pH 7.4 indicates tumor-targeting potential, with folic acid facilitating targeting of breast cancer cells. SEM imaging revealed that the freeze-dried optimized lipidic carriers had a spherical shape. Conclusion: This study demonstrated that folic acid functionalization enhances drug release at Triple-Negative Breast Cancer (TNBC) sites, while optimization using a central composite design identified statistically significant interactions between independent and dependent variables for FA-DAS-SLN.

Development of solid SEDDS, VII: Effect of pore size of silica on drug release from adsorbed self-emulsifying lipid-based formulations

LIN28 is a RNA binding protein and a pluripotency factor. It represses tumor suppressing microRNA let-7 and thus derepresses let-7 oncogene targets such as HMGA2, K-Ras and c-Myc. In addition, LIN28 binds and enhances translation of IGF-2 mRNA a known mitogen. Recent reports show that LIN28 overexpression promotes tumor cell migration and cellular transformation through repression of let-7, and that overexpression is associated with advanced stages of disease, including breast cancer. Despite the apparent critical role in cancer, the molecular function and mode of action of LIN28 is not yet elucidated. To further understand the function of LIN28, we explored LIN28 mRNA targets in breast cancer cells using RNA-protein immunoprecipitation (RIP-Chip) followed by RNA sequencing. Using RIP-Chip and RNA sequencing we have identified a number of novel LIN28 targets in MCF-7 breast cancer cells. Therapeutic drugs inhibiting LIN28 could be promising in treatment of cancer. Our experiments also demonstrate that MG132, a proteasome inhibitor, inhibits LIN28 expression and modulates expression of LIN28 mRNA targets in breast cancer cells. The mechanism by which LIN28 regulates its targets is unknown; however, a number of the new targets are important in cancer. Previous studies suggest that LIN28 acts through translational mechanisms. Studies are ongoing to reveal the mechanisms by which LIN28 regulates bound targets and how proteasome inhibitors impact this regulation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3082. doi:10.1158/1538-7445.AM2011-3082

Hyaluronic acid-coated capecitabine-loaded nanomicelles (HA-CAP-M) are synthesized to overcome the challenges associated with capecitabine (CAP) conventional delivery such as low permeability and systemic toxicity. Nanomicelles containing saponin, glycerol, and vitamin-E TPGS formulation of capecitabine were further encapsulated with hyaluronic acid (HA) for CD44 receptor-mediated targeting. Optimization of the formulation was carried out using a Box-Behnken design resulting in 17.8 nm particle size, 89.3% entrapment efficiency and a biphasic drug release profile. Characterization studies validated stability, spherical structure, and desirable encapsulation characteristics of the nanomicelles. Lowered critical micelle concentration (CMC) and acceptable drug release kinetics revealed improved thermodynamic stability and controlled drug release, as predicted by the Hixson-Crowell model. HA-CAP-M showed much higher permeability and cytotoxicity than the free CAP, with an IC50 of 2.964 μg mL-1 in in vitro experiments. AO/PI staining also demonstrated dose-dependent apoptosis in MCF-7 breast cancer cells and validated the highly effective active targeting of HA. In addition, the formulation demonstrated good stability during storage and dilution conditions, confirming its stability as a drug delivery platform. In conclusion, HA-functionalized nanomicelles provide a biocompatible and efficient system for the targeted breast cancer therapy, enhancing the therapeutic efficacy of capecitabine.

Two strategies to enhance ungual drug permeation from UV-cured films: Incomplete polymerisation to increase drug release and incorporation of chemical enhancers

The anti-HIV therapy is the most capable disease management approach for HIV-AIDS, but its purpose could not fulfill to get maximum bioavailability. In this study, an attempt has been made to develop lopinavir–loaded phospholipid vesicles by using the spray-drying method. Lopinavir loaded spray-dried powder (L-SDP) has been transformed into the vesicles and characterized for physico-chemical properties. Penetration enhancers (PEs) containing cream have been formulated to deliver L-SDP through the skin. Vesicle showed globular shape, 270 nm particle size, polydispersity index (PDI) 0.239, − 34.34 mV zeta potential with 56.38 ± 1.24% entrapment efficiency. In-vitro drug release (%) study through a cellophane membrane showed extended drug release of drug from liposomal formulations in contrast to hydro-alcoholic drug solution (HAS), which released most of the drug within 3–4 h and higher drug release than drug cream. The penetration enhancers (PEs) were selected after investigating their ability to enhance membrane fluidity by FTIR, which showed encouraging outcomes. L-SDP cream with PEs subjected for ex-vivo drug release and skin deposition study using goat facial skins. The cream showed superior drug deposition as well as drug release. The cream containing peppermint oil showed tenfold higher (57.2%) than drug cream (5.91%) and olive oil showed 44.9% drug release.

α-mangostin (AM) is a promising natural anticancer agent that can be used in cancer research. However, its effectiveness can be limited by poor solubility and bioavailability. To address this issue, chitosan-based nanoparticles (CSNPs) have been investigated as a potential delivery system to enhance the cytotoxicity to cancer cells and improve selectivity against normal cells. In this study, we developed folate-conjugated chitosan nanoparticles (F-CS-NPs) using a carbodiimide-based conjugation method to attach folate to chitosan (CS), which have different molecular weights. The NPs were crosslinked using tripolyphosphate (TPP) via ionic gelation. To characterize the F-CS-NPs, we utilized various analytical techniques, including transmission electron microscopy (TEM) to evaluate the particle size and morphology, Fourier-transform infrared spectroscopy (FTIR) to confirm the presence of functional groups, and ultraviolet-visible spectroscopy (UV-Vis) to measure the absorption spectrum and confirm the presence of folate. The particle size of AM-F-CS-NPs ranged from 180 nm to 250 nm, with many having favorable charges ranging from +40.33 ± 3.4 to 10.69 ± 1.3 mV. All NPs exhibited the same spherical morphology. The use of F-CS-NPs increased drug release, followed by a sustained release pattern. We evaluated the cytotoxicity of AM, AM-F-CS-HMW, and AM-F-CS-LMW NPs against MCF-7 cells and found IC50 values of 8.47 ± 0.49, 5.3 ± 0.01, and 4.70 ± 0.11 µg/mL, respectively. These results confirm the improved cytotoxicity of AM in MCF-7 cells when delivered via F-CS-NPs. Overall, our in vitro study demonstrated that the properties of F-CS-NPs greatly influence the cytotoxicity of AM in MCF-7 breast cancer cells (significantly different (p < 0.05)). The use of F-CS-NPs as a drug-delivery system for AM may have the potential to develop novel therapies for breast cancer.

NIR and glutathione trigger the surface release of methotrexate linked by Diels-Alder adducts to anisotropic gold nanoparticles

Objective: The main goal was to avoid all the problems associated with usual breast cancer treatment by using 6-thioguanine as a nanostructure lipid carrier (TG-NLCS). This was accomplished by administering an effective and targeted dose of 6-thioguanine (TG) to the tumour site using a long-lasting and biodegradable delivery system. Methods: A combination of heat homogenization and ultrasonication was used to implement the emulsification process. To obtain the optimal formulation, the prepared formulations were first assessed for particle size, Polydispersity Index (PDI), zeta potential, entrapment efficiency, and drug loading capacity. Additionally, a range of physicochemical characterization techniques were employed, including dissolution studies, melting point determination, Fourier-Transform Infrared (FTIR) spectroscopy, and Field Emission Scanning Electron Microscopy (FESEM), as well as cytotoxicity assessment of TG-NLCs in MCF-7 breast cancer cells. Results: The selected formula, TG03, showed a zeta potential of-13.5±0.27 mV and a particle size of 149±0.55 nm. This was further examined using a FESEM. In the in vitro drug release study, the formula demonstrated better-controlled drug release for 48 h in comparison to other formulations. In addition, the significant anti-proliferation activity of TG-NLCs against the MCF-7 breast cancer cell line. Conclusion: Nanostructured lipid carriers (NLCs) are one type of multifunctional nanoparticle that includes many combinations of lipids and medicines for various delivery routes.

Objective: The purpose of the present investigation is to formulate and evaluation of cubosome loaded in situ gel for fungal keratitis. Material and Method: The cubosomes were prepared by a top-down approach. Optimization of cubosome using box Behnken design. As formulation (independent) variables, lipid concentration (X1), poloxamer 407 concentration(X2), and homogenizer speed (X3) were used. The dependent variable was particle size (Y1), entrapment efficiency (Y2), and drug release(Y3) were investigated. 3-d surface plots and contour plots were drawn and optimized by feasibility and grid search. Identification of drug and drug-excipient compatibility study was carried out by DSC and FTIR. Particle size, PDI, and Zeta potential were analyzed by a zetatrac particle size analyzer. Entrapment efficiency, Invitro drug release study and SEM study were performed for characterization of nanoparticles. Viscosity, Gelation time and temperature, pH were performed for the characterization of nanoparticle-loaded in situ gel. An ocular irritancy study was performed on a rabbit. Result and Discussion: Cubosome was prepared by top-down method and optimized by Box-Behnken design and results show that particle size was found to be in the range of 200 to 350 nm, the entrapment efficiency was found to be in the range of 70-90%and drug release was found to be more than 80%. After preparing cubosome, that are incorporated into thermosensitive in situ gel for that carbopol 934: poloxamer 188 in the ratio of 1:20 were selected. The gelation time was found to be 41&plusmn;1 second and the gelation temperature was found to be 28 &plusmn; 0.70 &ordm;c. The checkpoint batch was formulated using the given value having predicted particle size, entrapment efficiency, and drug release respectively 209.106nm, 84.5541%, and 84.3765%, and actual (experimental) value particle size, entrapment efficiency, and drug release respectively 207.88nm, 83.79%, and 82.94%. That shows less % relative error. From the image, the surface of cubosomes can be easily studied as to whether it has a cubic shape. The drug was 90.22 % diffused after 4 hrs. study of the Franz diffusion cell. In the ocular irritancy, study results indicate that the optimized in situ gelling system was non-irritant and well tolerated by the rabbit&rsquo;s eyes. Conclusion: In this study cubosome loaded in situ gel for fungal keratitis in the ocular route demonstrate that the ocular route is a promising approach and may improve the retention time of drug by the ocular route and reduce side effects related to other routes also improve patient compliance. This cubogel is an ocular dosage form to boost corneal permeability and bioavailability. The developed novel formulation is promising for the ocular delivery of a drug.