scholarly journals Nano Co-Crystal Embedded Stimuli-Responsive Hydrogels: A Potential Approach to Treat HIV/AIDS

Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 127
Author(s):  
Bwalya A. Witika ◽  
Jessé-Clint Stander ◽  
Vincent J. Smith ◽  
Roderick B. Walker
Keyword(s):  
Cell Viability ◽  
Gelation Time ◽  
In Vitro Cytotoxicity ◽  
Physical Mixture ◽  
In Vitro Dissolution ◽  
Order Kinetic ◽  
Stimuli Responsive ◽  
Thermoresponsive Hydrogel ◽  
Immunodeficiency Syndrome

Currently, the human immunodeficiency virus (HIV) that causes acquired immunodeficiency syndrome (AIDS) can only be treated successfully, using combination antiretroviral (ARV) therapy. Lamivudine (3TC) and zidovudine (AZT), two compounds used for the treatment of HIV and prevention of disease progression to AIDS are used in such combinations. Successful therapy with 3TC and AZT requires frequent dosing that may lead to reduced adherence, resistance and consequently treatment failure. Improved toxicity profiles of 3TC and AZT were observed when combined as a nano co-crystal (NCC). The use of stimuli-responsive delivery systems provides an opportunity to overcome the challenge of frequent dosing, by controlling and/or sustaining delivery of drugs. Preliminary studies undertaken to identify a suitable composition for a stimulus-responsive in situ forming hydrogel carrier for 3TC-AZT NCC were conducted, and the gelation and erosion time were determined. A 25% w/w Pluronic® F-127 thermoresponsive hydrogel was identified as a suitable carrier as it exhibited a gelation time of 5 min and an erosion time of 7 days. NCC-loaded hydrogels were evaluated using in vitro dissolution and cytotoxicity assays. In vitro dissolution undertaken using membrane-less diffusion over 168 h revealed that 3TC and AZT release from NCC-loaded hydrogels was complete and followed zero-order kinetic processes, whereas those loaded with the micro co-crystal and physical mixture were incomplete and best described using the Korsmeyer–Peppas kinetic model. The release of AZT and 3TC from the physical mixture and MCC-loaded gel exhibited a value for n of 0.595 for AZT release from the physical mixture and 0.540 for the MCC technology, whereas the release exponent for 3TC was 0.513 for the physical mixture and 0.557 for the MCC technology indicating that diffusion and erosion controlled 3TC and AZT release. In vitro cytotoxicity assay data revealed that the addition of NCC to the thermoresponsive hydrogel resulted in an improved cell viability of 88.0% ± 5.0% when compared to the cell viability of the NCC of 76.9% ± 5.0%. The results suggest that the use of a thermoresponsive nanosuspension may have the potential to be delivered as an intramuscular injection that can subsequently increase bioavailability and permit dose reduction and/or permit use of a longer dosing frequency.

scholarly journals Multiresponsive Hybrid Microparticles for Stimuli-Responsive Delivery of Bioactive Compounds

2020 ◽  
Vol 10 (12) ◽  
pp. 4324 ◽  
Author(s):  
Sergei S. Vlasov ◽  
Pavel S. Postnikov ◽  
Mikhail V. Belousov ◽  
Sergei V. Krivoshchekov ◽  
Mekhman S. Yusubov ◽  
...  
Keyword(s):  
Cell Viability ◽  
Spherical Shape ◽  
In Vitro Cytotoxicity ◽  
Poly Lactic Acid ◽  
Iron Core ◽  
Stimuli Responsive ◽  
Ultrasonic Fields ◽  
Burst Intensity ◽  
Free Doxorubicin

Hybrid microparticles based on an iron core and an amphiphilic polymeric shell have been prepared to respond simultaneously to magnetic and ultrasonic fields and variation in the surrounding pH to trigger and modulate the delivery of doxorubicin. The microparticles have been developed in four steps: (i) synthesis of the iron core; (ii) surface modification of the core; (iii) conjugation with the amphiphilic poly(lactic acid)-grafted chitosan; and (iv) doxorubicin loading. The particles demonstrate spherical shape, a size in the range of 1–3 µm and surface charge that is tuneable by changing the pH of the environment. The microparticles demonstrate good stability in simulated physiological solutions and are able to hold up to 400 µg of doxorubicin per mg of dried particles. The response to ultrasound and the changes in the shell structure during exposure to different pH levels allows the control of the burst intensity and release rate of the payload. Additionally, the magnetic response of the iron core is preserved despite the polymer coat. In vitro cytotoxicity tests performed on fibroblast NIH/3T3 demonstrate a reduction in the cell viability after administration of doxorubicin-loaded microparticles compared to the administration of free doxorubicin. The application of ultrasound causes a burst in the release of the doxorubicin from the carrier, causing a decrease in cell viability. The microparticles demonstrate in vitro cytocompatibility and hemocompatibility at concentrations of up to 50 and 60 µg/mL, respectively.

Formulation, Characterization and In vitro Cytotoxicity of 5-Fluorouracil Loaded Polymeric Electrospun Nanofibers for the Treatment of Skin Cancer

2019 ◽  
Vol 13 (2) ◽  
pp. 114-128 ◽  
Author(s):  
Gayatri Patel ◽  
Bindu K.N. Yadav
Keyword(s):  
Skin Cancer ◽  
Basal Cell Carcinoma ◽  
Cell Viability ◽  
Cell Carcinoma ◽  
Basal Cell ◽  
Fiber Diameter ◽  
Electrospun Nanofibers ◽  
In Vitro Cytotoxicity ◽  
Fractional Factorial

Background: The purpose of this study was to formulate, characterize and conduct in vitro cytotoxicity of 5-fluorouracil loaded polymeric electrospun nanofibers for the treatment of skin cancer. The patents on electrospun nanofibers (US9393216B2), (US14146252), (WO2015003155A1) etc. helped in the selection of polymers and method for the preparation of nanofibers. Methods: In the present study, the fabrication of nanofibers was done using a blend of chitosan with polyvinyl alcohol and processed using the electrospinning technique. 5-fluorouracil with known chemotherapeutic potential in the treatment of skin cancer was used as a drug carrier. 24-1 fractional factorial screening design was employed to study the effect of independent variables like the concentration of the polymeric solution, applied voltage (kV), distance (cm), flow rate (ml / hr) on dependent variables like % entrapment efficiency and fiber diameter. Results: Scanning electron microscopy was used to characterize fiber diameter and morphology. Results showed that the fiber diameter of all batches was found in the range of 100-200 nm. The optimized batch results showed the fiber diameter of 162.7 nm with uniform fibers. The tensile strength obtained was 190±37 Mpa. Further in vitro and ex vivo drug release profile suggested a controlled release mechanism for an extended period of 24 hr. The 5-fluorouracil loaded electrospun nanofibers were found to decrease cell viability up to ≥50% over 24 hr, with the number of cells dropping by ~ 10% over 48 hr. As the cell viability was affected by the release of 5-fluorouracil, we believe that electrospun nanofibers are a promising drug delivery system for the treatment of Basal Cell Carcinoma (BCC) skin cancer. Conclusion: These results demonstrate the possibility of delivering 5-Fluorouracil loaded electrospun nanofiber to skin with enhanced encapsulation efficiency indicating the effectiveness of the formulation for the treatment of basal cell carcinoma type of skin cancer.

scholarly journals Preparation and Evaluation of Inclusion Complex of the Lipid Lowering Drug Lovastatin with ?-Cyclodextrin

1970 ◽  
Vol 6 (1) ◽  
pp. 25-36 ◽  
Author(s):  
RP Patel ◽  
MM Patel
Keyword(s):  
Dissolution Rate ◽  
Inclusion Complexation ◽  
Physical Mixture ◽  
Lipid Lowering ◽  
In Vitro Dissolution ◽  
Phase Solubility ◽  
Stoichiometric Ratio ◽  
Significant Difference ◽  
Insoluble Drugs

Several attempts have been made to improve the solubility of water insoluble drugs. Over the years, inclusion complexation of drugs with ?-cyclodextrin has emerged as a viable attempt to improve the dissolution of water insoluble drugs. The aim of the present work was to improve the dissolution rate of lovastatin, a water insoluble drug, by inclusion complexation with ?-cyclodextrin. The stoichiometric ratio determined by phase solubility analysis for inclusion complexation of lovastatin with ?-cyclodextrin was 1:1. The solubility of lovastatin increased with increasing amount of ?-cyclodextrin in water. Gibbs free energy (?Gtr°) values were all negative, indicating the spontaneous nature of lovastatin solubilization. Complexes of lovastatin were prepared with ?-cyclodextrin by various methods such as kneading, coevaporation and physical mixing. The complexes were characterized by Fourier-transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) patterns. These studies indicated the inclusion of lovastatin in the cavity of ?-cyclodextrin. The complexation resulted in a marked improvement in the solubility of lovastatin. The complex prepared by kneading method showed fastest and highest in vitro dissolution rate compared to the tablets of pure of lovastatin. Physical mixture of ?-cyclodextrin/lovastatin also showed significant improvement in the dissolution rate compared to pure lovastatin. Mean dissolution time (MDT) of lovastatin decreased significantly after preparation of complexes and physical mixture of lovastatin with ?-cyclodextrin. Similarity factor (f2) indicated significant difference between the release profiles of lovastatin from complexes and from pure lovastatin. Key words: Lovastatin, ?-cyclodextrin, inclusion complexation, in vitro dissolution studies. Dhaka Univ. J. Pharm. Sci. 6(1): 25-36, 2007 (June) The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website

scholarly journals In-Vitro Cytotoxicity Study: Cell Viability and Cell Morphology of Carbon Nanofibrous Scaffold/Hydroxyapatite Nanocomposites

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1552
Author(s):  
Asmaa M. Abd El-Aziz ◽  
Azza El-Maghraby ◽  
Andrea Ewald ◽  
Sherif H. Kandil
Keyword(s):  
Heat Treatment ◽  
Cell Viability ◽  
Cell Morphology ◽  
Bone Cell ◽  
In Vitro Cytotoxicity ◽  
Cell Counting ◽  
Hydrothermal Modification ◽  
Bone Cell Proliferation ◽  
L929 Mouse

Electrospun carbon nanofibers (CNFs), which were modified with hydroxyapatite, were fabricated to be used as a substrate for bone cell proliferation. The CNFs were derived from electrospun polyacrylonitrile (PAN) nanofibers after two steps of heat treatment: stabilization and carbonization. Carbon nanofibrous (CNF)/hydroxyapatite (HA) nanocomposites were prepared by two different methods; one of them being modification during electrospinning (CNF-8HA) and the second method being hydrothermal modification after carbonization (CNF-8HA; hydrothermally) to be used as a platform for bone tissue engineering. The biological investigations were performed using in-vitro cell counting, WST cell viability and cell morphology after three and seven days. L929 mouse fibroblasts were found to be more viable on the hydrothermally-modified CNF scaffolds than on the unmodified CNF scaffolds. The biological characterizations of the synthesized CNF/HA nanofibrous composites indicated higher capability of bone regeneration.

scholarly journals Improvement in vitro Dissolution Rate of Quercetin Using Cocrystallization of Quercetin-Malonic Acid

2018 ◽  
Vol 18 (3) ◽  
pp. 531 ◽  
Author(s):  
Dwi Setyawan ◽  
Sukma Adhi Permata ◽  
Ahmad Zainul ◽  
Maria Lucia Ardhani Dwi Lestari
Keyword(s):  
Dissolution Rate ◽  
Malonic Acid ◽  
Fourier Transforms ◽  
Solvent Evaporation ◽  
Physical Mixture ◽  
Original Position ◽  
In Vitro Dissolution ◽  
Solvent Evaporation Method ◽  
Evaporation Method

The aim of the study was to improve the in-vitro dissolution rate of quercetin (Qu) using cocrystallization of quercetin. Cocrystals of quercetin (Co Qu) were produced with malonic acid (Ma) as coformer at ratio 1:2 using solvent evaporation method. Cocrystals quercetin-malonic acid (Co Qu-Ma) was characterized using Differential Thermal Analysis (DTA), Powder X-Ray Diffraction (PXRD), Scanning Electron Microscope (SEM), and Fourier Transforms Infrared Spectrophotometer (FTIR) and in-vitro dissolution study. A new endothermic peak at 277.9 °C was shown from the thermogram. Diffractogram of Co Qu-Ma showed a new diffraction peak at 2θ 9.81, 12.99, and 19.80°. Microphotograph showed that Qu and Ma exhibited a columnar-shaped and a pebble-shaped crystal, respectively, and FTIR wavenumber of O-H functional group of quercetin was shifted from its original position at 3411 to 3428 cm-1 in the physical mixture (pm) of Qu-Ma and 3418 cm-1 in Co Qu-Ma, respectively. The physicochemical characterizations using DTA, PXRD, SEM and FTIR indicated that Co Qu-Ma were successfully obtained through solvent evaporation method. The in-vitro dissolution rate of Co Qu-Ma was 95.30% at 60 min. Cocrystals effectively increased dissolution rate and dissolution efficiency in comparison to the pure quercetin and physical mixture of quercetin-malonic acid.

In Vitro Cytotoxicity Evaluation of Oxytetracycline Loaded Cockle Shell Derived Calcium Carbonate Aragonite Nanoparticles

2020 ◽  
Vol 10 ◽  
Author(s):  
Sherifat Banke Idris ◽  
Abdul Kadir Arifah ◽  
Faez Firdaus Abdullah Jesse ◽  
Siti Zubaidah Ramanoon ◽  
Muhammad Abdul Basit ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Cell Viability ◽  
Trypan Blue ◽  
Pharmaceutical Formulations ◽  
In Vitro Cytotoxicity ◽  
Mouse Fibroblast ◽  
Nih3t3 Cells ◽  
Toxicological Assessment ◽  
Culture Models

Background: Evaluation of the toxic effects of nanoparticle-drug in vitro is an important step in the design of new pharmaceutical formulations. Rapid results, reduced cost and easy handling makes cell culture models first line in initial toxicological assessment of nanodrug preparations. Objective: To evaluate the in vitro cytotoxicity of oxytetracycline loaded calcium carbonate aragonite nanoparticle in normal mouse fibroblast (NIH3T3) cell line. Method: NIH3T3 cells were exposed to varying concentrations (6.25 - 100µg/mL) of calcium carbonate aragonite nanoparticle (CS-CaCO3NP), oxytetracycline loaded calcium carbonate aragonite nanoparticle (OTC-CS-CaCO3NP) and oxytetracycline (OTC) in 96 well plates for 24, 48 and 72 hours. Cell viability was determined by MTT and trypan blue assays. Result: Both assays show that CS-CaCO3NP and OTC-CS-CaCO3NP had higher cell viability values compared to OTC. Conclusion: Encapsulating OTC into CS-CaCO3NP reduced its cytotoxicity to NIH3T3 cells using both MTT and trypan blue assay.

Solubility Enhancement of Hydrochlorothiazide using a Novel Drug-Drug Solid Dispersion Technology

2015 ◽  
Vol 8 (3) ◽  
pp. 2924-2936
Author(s):  
Rakshit N Sonpal ◽  
Pragna Shelat ◽  
Anita Lalwani
Keyword(s):  
Solid Dispersion ◽  
Aqueous Solubility ◽  
Physical Mixture ◽  
In Vitro Dissolution ◽  
Fixed Dose ◽  
Pharmacokinetic Analysis ◽  
Metoprolol Tartrate ◽  
Pure Drug ◽  
Novel Drug

Fixed dose combination (FDC) is commonly used in pharmaceuticals to reduce pill burden and optimize the drug therapy. The recent advancements in combinatorial chemistry often lead to drugs with low aqueous solubility. Many FDC’s contain at least one drug with suboptimal physicochemical properties like BCS class II drugs for which its poor aqueous solubility may often be a limiting factor to its bioavailability. Considering the above fact, a novel drug – drug solid dispersion has been developed in present study, wherein a poorly soluble drug hydrochlorothiazide has been solid dispersed in a hydrophilic drug, Metoprolol tartrate with which it is available as a FDC. Hydrochlorothiazide was solid dispersed in Metoprolol tartrate in ratios as available in market and also in conventional carrier mannitol by melting method. Physical mixtures of the two drugs and hydrochlorothiazide and mannitol were also prepared in the same ratio. Physical mixture did not show any signs of incompatibility in the FTIR study. In vitro dissolution study showed that t90% was less for solid dispersion (SDMT4) as compared to pure drug and physical mixture of the two drugs and so was selected for further study. The SDMT4 batch was then subjected to DSC analysis and XRD study, where the results suggested amorphization of hydro-chlorothiazide. Tablets were prepared from the SDMT4 batch and the in vitro release profile was compared to marketed formulation of hydrochlorothiazide. Tablets were subjected to accelerated stability analysis for 6 months at 40 °C and 75 % RH and were found to remain stable. Pharmacokinetic analysis was carried out with pure drug and SDMT4 and relative bioavailability was estimated to be 1.21. Thus a novel concept where in one drug is solid dispersed in other was hypothesized and proved. The concept can be explored for many such FDC’s.

Evaluation of the Influence of Ferrite Magnetic Nanoparticle for Cancer Cell

2021 ◽  
Vol 323 ◽  
pp. 146-151
Author(s):  
Khishigdemberel Ikhbayar ◽  
Nomin Myagmar ◽  
Gantulga Davaakhuu ◽  
Uyanga Enkhnaran ◽  
Enkhmend Bekhbaatar ◽  
...  
Keyword(s):  
Cell Viability ◽  
Colony Formation ◽  
Magnetic Nanoparticle ◽  
In Vitro Cytotoxicity ◽  
Colony Formation Assay ◽  
Cell Viability Assay ◽  
Cytotoxic Effects ◽  
Viability Assay ◽  
A Cell

Magnetic nanoparticles for thermotherapy must be biocompatible and possess high thermal efficiency as heating elements. The biocompatibility of Mg 0.8 Ni 0.2 Fe 2 O 4 nanoparticles was studied using a cytotoxicity colony formation assay and a cell viability assay. HeLa cells exhibited cytotoxic effects when exposed to three different concentrations of 150 μg /ml, 100 μg /ml, and 50 μg /ml nanoparticles. Therefor e, c oncentrations of 50 μg /ml showed the lowest cytotoxic activity and the lowest toxicity to living cells. In vitro cytotoxicity of samples was then investigated by two methods, colony formation assay and cell viability assay. The Hela inhibited cell growth as 16.8% during heating by magnetic field generators.

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