scholarly journals Injectable Vaginal Hydrogels as a Multi-Drug Carrier for Contraception

2019 ◽  
Vol 9 (8) ◽  
pp. 1638 ◽  
Author(s):  
Nie ◽  
Zou ◽  
Dong ◽  
Sun ◽  
Ding ◽  
...  
Keyword(s):  
Ethinyl Estradiol ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Temperature Sensitive ◽  
Dosage Group ◽  
Contraceptive Effect ◽  
Poly Ethylene ◽  
Release Profiles

Injectable intravaginal hydrogels could deliver drugs systemically without hepatic first pass effect. This paper focuses on the contraceptive function of an injectable temperature-sensitive four-arm star-shaped poly(D,L-lactic-co-glycolic acid)-b-methoxy poly(ethylene glycol) (4sPLGA-mPEG) block copolymer hydrogels as a carrier of three drugs. In vitro controlled release profiles were investigated via HPLC, and it showed that the cumulative release amounts of indomethacin (IMC), gestodene (GSD), and ethinyl estradiol (EE) from copolymer hydrogels could be regulated by adjusting the lactide/glycolide (LA/GA) mol ratio. In addition, in vitro release profiles of IMC, GSD, and EE well corresponded to Higuchi model. The acute toxicity of copolymer hydrogels loaded with different dosage contents multi-drug was evaluated in vivo. As to the high dosage group, the uterus was hydropic at day 1 and ulcerated at day 5, followed with intestinal adhesion. Regarding the middle dosage group, no festering of tissues was observed and, blood coagulum existed in the uterus at different days. For low dosage group, no significant tissue necrosis was found. Finally, the antifertility experiments confirmed that hydrogels loaded with the multi-drug had an excellent contraceptive effect. The above results indicated that injectable copolymer hydrogel as a multi-drug carrier was promising as a novel contraception method.

scholarly journals Comparative Analysis of Morphological and Release Profiles in Ocular Implants of Acetazolamide Prepared by Electrospinning

Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 260
Author(s):  
Mariana Morais ◽  
Patrícia Coimbra ◽  
Maria Eugénia Pina
Keyword(s):  
Drug Release ◽  
In Vitro Release ◽  
Morbidity Rate ◽  
Coating Film ◽  
Sustained Drug Release ◽  
Coated Implant ◽  
Poly Ethylene ◽  
Coaxial Fibers ◽  
Release Profiles

The visual impairment that often leads to blindness causes a higher morbidity rate. The goal of this work is to create a novel biodegradable polymeric implant obtained from coaxial fibers containing the dispersed drug—acetazolamide—in order to achieve sustained drug release and increase patient compliance, which is of the highest importance. Firstly, during this work, uncoated implants were produced by electrospinning, and rolled in the shape of small cylinders that were composed of uniaxial and coaxial fibers with immobilized drug inside. The fibers were composed by PCL (poly ε-caprolactone) and Lutrol F127 (poly (oxyethylene-b-oxypropylene-b-oxyethylene)). The prepared implants exhibited a fast rate of drug release, which led to the preparation of new implants incorporating the same formulation but with an additional coating film prepared by solvent casting and comprising PCL and Lutrol F127 or PCL and Luwax EVA 3 ((poly (ethylene-co-vinyl acetate)). Implants were characterized and in vitro release profiles of acetazolamide were obtained in phosphate buffered saline (PBS) at 37 °C. The release profile of the acetazolamide from coated implant containing Luwax EVA 3 is considerably slower than what was observed in case of coated implants containing Lutrol F127, allowing a sustained release and an innovation relatively to other ocular drug delivery systems.

scholarly journals Folate-Functionalized Mesoporous Hollow SnO2 Nanofibers as a Targeting Drug Carrier to Improve the Antitumor Effect of Paclitaxel for Liver Cancer Therapy

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Huiling Lv ◽  
Chao Wu ◽  
Xuan Liu ◽  
Andi Bai ◽  
Yue Cao ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Liver Cancer ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Hollow Structure ◽  
Amorphous State ◽  
Outer Diameter ◽  
Drug Delivery Carrier

In this study, we prepared PTX-loaded mesoporous hollow SnO2 nanofibers conjugated with folic acid (SFNFP) for liver cancer therapy. According to SEM and TEM characterization, SFNF showed a mesoporous hollow structure. The average outer diameter was 200 nm, and the wall thickness was 50 nm. The DSC and XRD study showed that PTX in the channels of nanofibers was present in an amorphous state. The in vitro release experiments demonstrated that SFNF could efficiently improve the dissolution rate of PTX. Both in vitro cell experiments and in vivo antitumor experiments showed that SFNFP could efficiently inhibit the growth of liver cancer cells. Therefore, SFNF is a promising targeting antitumor drug delivery carrier.

scholarly journals In vitro Release and in vivo Anti-tumor Efficacy of Doxorubicin from Biodegradable Temperature-sensitive Star-shaped PLGA-PEG Block Copolymer Hydrogel

2007 ◽  
Vol 40 (2) ◽  
pp. 171-176 ◽  
Author(s):  
Su Jeong Lee ◽  
Yoonsoo Bae ◽  
Kazunori Kataoka ◽  
Dukjoon Kim ◽  
Doo Sung Lee ◽  
...  
Keyword(s):  
Block Copolymer ◽  
In Vitro Release ◽  
Temperature Sensitive ◽  
Copolymer Hydrogel ◽  
Vitro Release

scholarly journals Delay Tumor Growth Properties of LA-PEG-G Molecule and Its' Application as Drug Carrier

2020 ◽  
Author(s):  
guangcheng wei ◽  
Meixiu Xin ◽  
Hao Wang ◽  
Yehong Huo ◽  
Wei Hu ◽  
...  
Keyword(s):  
Tumor Growth ◽  
Antitumor Effect ◽  
Drug Carrier ◽  
In Vitro Release ◽  
Serum Biochemistry ◽  
Delay Tumor Growth ◽  
In Vivo Experiments ◽  
Low Cytotoxicity

Abstract LA–PEG–G molecule was prepared through the covalent conjugation of linoleic acid, polyethylene glycol and guanosine. LA–PEG–G molecule can self-assemble into spherical aggregate in aqueous solution. The size of the LA–PEG–G aggregate was approximately 132.1 ± 13.718 nm, and the Zeta potential was −36.3 ± 0.9644 mv. The loading rate of LA–PEG–G aggregates to Dox was 84.62 ± 1.810%. In vitro release experiments showed that Dox release from the LA–PEG–G–Dox nanomedicine was slow-release. Cell experiments showed that LA–PEG–G aggregates have low cytotoxicity, and the relative cancer cells survival rate decreased with the increasing of time and LA–PEG–G–Dox nanomedicine concentration. In vivo experiments showed that LA–PEG–G–Dox nanomedicine can inhibit tumor growth, and the LA–PEG–G aggregate could also delay the tumor growth which is very important to play the synergistic antitumor effect with the anticancer drug. Serum biochemistry showed that LA–PEG–G–Dox nanomedicine which reduced the Dox toxicity had very good antitumor effect. The tumor tissue sections indicated that LA–PEG–G–Dox nanomedicine can effectively induce tumor cell apoptosis, and finally cause tissue necrosis to achieve tumor treatment.

scholarly journals Dexamethasone PLGA Microspheres for Sub-Tenon Administration: Influence of Sterilization and Tolerance Studies

Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 228
Author(s):  
Deyanira Barbosa-Alfaro ◽  
Vanessa Andrés-Guerrero ◽  
Ivan Fernandez-Bueno ◽  
María Teresa García-Gutiérrez ◽  
Esther Gil-Alegre ◽  
...  
Keyword(s):  
Particle Size ◽  
In Vitro Release ◽  
Intravitreal Injections ◽  
Plga Microspheres ◽  
Promising Alternative ◽  
Before And After ◽  
Evaporation Technique ◽  
Release Profiles

Many diseases affecting the posterior segment of the eye require repeated intravitreal injections with corticosteroids in chronic treatments. The periocular administration is a less invasive route attracting considerable attention for long-term therapies. In the present work, dexamethasone-loaded poly(lactic-co-glycolic) acid (PLGA) microspheres (Dx-MS) were prepared using the oil-in-water (O/W) emulsion solvent evaporation technique. MS were characterized in terms of mean particle size and particle size distribution, external morphology, polymer integrity, drug content, and in vitro release profiles. MS were sterilized by gamma irradiation (25 kGy), and dexamethasone release profiles from sterilized and non-sterilized microspheres were compared by means of the similarity factor (f2). The mechanism of drug release before and after irradiation exposure of Dx-MS was identified using appropriate mathematical models. Dexamethasone release was sustained in vitro for 9 weeks. The evaluation of the in vivo tolerance was carried out in rabbit eyes, which received a sub-Tenon injection of 5 mg of sterilized Dx-MS (20–53 µm size containing 165.6 ± 3.6 µg Dx/mg MS) equivalent to 828 µg of Dx. No detectable increase in intraocular pressure was reported, and clinical and histological analysis of the ocular tissues showed no adverse events up to 6 weeks after the administration. According to the data presented in this work, the sub-Tenon administration of Dx-MS could be a promising alternative to successive intravitreal injections for the treatment of chronic diseases of the back of the eye.

scholarly journals In Vitro–In Vivo Correlation (IVIVC) Population Modeling for the In Silico Bioequivalence of a Long-Acting Release Formulation of Progesterone

Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 255
Author(s):  
Elena M. Tosca ◽  
Maurizio Rocchetti ◽  
Elena Pérez ◽  
Conchi Nieto ◽  
Paolo Bettica ◽  
...  
Keyword(s):  
Clinical Studies ◽  
In Vitro Release ◽  
Release Formulation ◽  
Mixed Effect ◽  
Ring Model ◽  
Long Acting ◽  
Vitro Release ◽  
Release Profiles

Health authorities carefully evaluate any change in the batch manufacturing process of a drug before and after regulatory approval. In the absence of an adequate in vitro–in vivo correlation (Level A IVIVC), an in vivo bioequivalence (BE) study is frequently required, increasing the cost and time of drug development. This study focused on developing a Level A IVIVC for progesterone vaginal rings (PVRs), a dosage form designed for the continuous delivery in vivo. The pharmacokinetics (PK) of four batches of rings charged with 125, 375, 750 and 1500 mg of progesterone and characterized by different in vitro release rates were evaluated in two clinical studies. In vivo serum concentrations and in vitro release profiles were used to develop a population IVIVC progesterone ring (P-ring) model through a direct differential-equation-based method and a nonlinear-mixed-effect approach. The in vivo release, Rvivo(t), was predicted from the in vitro profile through a nonlinear relationship. Rvivo(t) was used as the input of a compartmental PK model describing the in vivo serum concentration dynamics of progesterone. The proposed IVIVC P-ring model was able to correctly predict the in vivo concentration–time profiles of progesterone starting from the in vitro PVR release profiles. Its internal and external predictability was carefully evaluated considering the FDA acceptance criteria for IVIVC assessment of extended-release oral drugs. Obtained results justified the use of the in vitro release testing in lieu of clinical studies for the BE assessment of any new PVRs batches. Finally, the possible use of the developed population IVIVC model as a simulator of virtual BE trials was explored through a case study.

Reliability of a Single β-Thromboglobulin Measurement in a Diabetic Population : Importance of PGE1 in Anticoagulant Mixture

1987 ◽  
Vol 57 (02) ◽  
pp. 201-204 ◽  
Author(s):  
P Y Scarabin ◽  
L Strain ◽  
C A Ludlam ◽  
J Jones ◽  
E M Kohner
Keyword(s):  
In Vitro Release ◽  
Mean Value ◽  
Reliable Estimate ◽  
Diabetic Patients ◽  
Single Measurement ◽  
Diabetic Population ◽  
The Difference ◽  
Vitro Release

SummaryDuring the collection of samples for plasma β-thromboglobulin (β-TG) determination, it is well established that artificially high values can be observed due to in-vitro release. To estimate the reliability of a single β-TG measurement, blood samples were collected simultaneously from both arms on two separate occasions in 56 diabetic patients selected for a clinical trial. From each arm, blood was taken into two tubes containing an anticoagulant mixture with (tube A) and without (tube B) PGE!. The overall mean value of B-TG in tube B was 1.14 times higher than in tube A (p <0.01). The markedly large between-arms variation accounted for the most part of within-subject variation in both tubes and was significantly greater in tube B than in tube A. Based on the difference between B-TG values from both arms, the number of subjects with artifically high B-TG values was significantly higher in tube B than in tube A on each occasion (overall rate: 28% and 14% respectively). Estimate of between-occasions variation showed that B-TG levels were relatively stable for each subject between two occasions in each tube. It is concluded that the use of PGEi decreases falsely high B-TG levels, but a single measurement of B-TG does not provide a reliable estimate of the true B-TG value in vivo.

Fenofibrate Solid Dispersion for Improving Oral Bioavailability: Preparation, and Characterization and in vivo Evaluation

2020 ◽  
Vol 13 (5) ◽  
pp. 5102-5109
Author(s):  
Venu Madhav K ◽  
Somnath De ◽  
Chandra Shekar Bonagiri ◽  
Sridhar Babu Gummadi
Keyword(s):  
Oral Bioavailability ◽  
Oral Delivery ◽  
Solid Dispersions ◽  
In Vitro Release ◽  
Aqueous Solubility ◽  
Water Soluble ◽  
Scanning Calorimetry ◽  
In Vivo Evaluation

Fenofibrate (FN) is used in the treatment of hypercholesterolemia. It shows poor dissolution and poor oral bioavailability after oral administration due to high liphophilicity and low aqueous solubility. Hence, solid dispersions (SDs) of FN (FN-SDs) were develop that might enhance the dissolution and subsequently oral bioavailability. FN-SDs were prepared by solvent casting method using different carriers (PEG 4000, PEG 6000, β cyclodextrin and HP β cyclodextrin) in different proportions (0.25%, 0.5%, 0.75% and 1% w/v). FN-SDs were evaluated solubility, assay and in vitro release studies for the optimization of SD formulation. Differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) analysis was performed for crystalline and morphology analysis, respectively. Further, optimized FN-SD formulation evaluated for pharmacokinetic performance in Wistar rats, in vivo in comparison with FN suspension.  From the results, FN-SD3 and FN-SD6 have showed 102.9 ±1.3% and 105.5±3.1% drug release, respectively in 2 h. DSC and PXRD studies revealed that conversion of crystalline to amorphous nature of FN from FT-SD formulation. SEM studies revealed the change in the orientation of FN when incorporated in SDs. The oral bioavailability FN-SD3 and FN-SD6 formulations exhibited 2.5-folds and 3.1-folds improvement when compared to FN suspension as control. Overall, SD of FN could be considered as an alternative dosage form for the enhancement of oral delivery of poorly water-soluble FN.

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