Prolonged release of insulin by cholesterol-matrix implant

Diabetes ◽  
1987 ◽  
Vol 36 (9) ◽  
pp. 1068-1072 ◽  
Author(s):  
P. Y. Wang
Keyword(s):  
2019 ◽  
Vol 41 (4) ◽  
pp. 271-278
Author(s):  
S.A. Lukashevich ◽  
◽  
R.A. Rozhnova ◽  
G.A. Kozlova ◽  
L.Yu. Nechaeva ◽  
...  

Author(s):  
Mohammed Ibrahim ◽  
Alaa Zaky ◽  
Mohsen Afouna ◽  
Ahmed Samy

Carrier erythrocytes are emerging as one of the most promising biological drug delivery systems investigated in recent decades. Beside its biocompatibility, biodegradability and ability to circulate throughout the body, it has the ability to perform extended release system of the drug for a long period. The ultimate goal of this study is to introduce a new carrier system for Salbutamol, maintaining suitable blood levels for a long time, as atrial to resolve the problems of nocturnal asthma medication Therefore in this work we study the effect of time, temperature as well as concentration on the loading of salbutamol in human erythrocytes to be used as systemic sustained release delivery system for this drug. After the loading process is performed the carrier erythrocytes were physically and cellulary characterized. Also, the in vitro release of salbutamol from carrier erythrocytes was studied over time interval. From the results it was found that, human erythrocytes have been successfully loaded with salbutamol using endocytosis method either at 25 Co or at 37 Co . The highest loaded amount was 3.5 mg/ml and 6.5 mg/ml respectively. Moreover, the percent of cells recovery is 90.7± 1.64%. Hematological parameters and osmotic fragility behavior of salbutamol loaded erythrocytes were similar that of native erythrocytes. Scanning electron microscopy demonstrated that the salbutamol loaded cells has moderate change in the morphology. Salbutamol releasing from carrier cell was 43% after 36 hours in phosphate buffer saline. The releasing pattern of the drug from loaded erythrocytes showed initial burst release in the first hour followed by a very slow release, obeying zero order kinetics. It concluded that salbutamol is successfully entrapped into erythrocytes with acceptable loading parameters and moderate morphological changes, this suggesting that erythrocytes can be used as prolonged release carrier for salbutamol.


Author(s):  
C Suja ◽  
Sismy C

The goal of this study was to formulate and evaluate norfloxacin sustained release tablets. Norfloxacin sustained release tablets were prepared by wet granulation method using two polymers such as HPMC K 100 M (hydrophilic polymer) and guar gum (natural polymer) and with three polymer ratios (0.5, 1.0 and 1.5). The prepared granules were evaluated to preformulation studies such as angle of repose, bulk density, tapped density, bulkiness, compressibility index and Hauser’s ratio. All the parameters shows that the granules having good flow properties. Then the formulated tablets were taken to evaluation studies such as hardness, weight variation, friability, drug content and thickness. All the parameters were within the acceptable limits. IR spectral analysis showed that there was no interaction between the drug and polymers. The in vitro release study was performed in phosphate buffer pH 7.4 at 293 nm. The in vitro release study showed that if the polymer ratio is increased, then the release of the drug is prolonged. HPMC K 100M shows a prolonged release when compared to guar gum.


2020 ◽  
Vol 26 (27) ◽  
pp. 3251-3268
Author(s):  
Shweta Ramkar ◽  
Abhishek K. Sah ◽  
Nagendra Bhuwane ◽  
Ishwari Choudhary ◽  
Narayan Hemnani ◽  
...  

The pilosebaceous unit is the triad comprising of hair follicle, arrector pilli muscle, and sebaceous gland. Drug delivery to and through the hair follicles has garnered much attention of the researchers and the hair follicles represent an attractive target site via topical applications. They are bordered by capillaries and antigenpresenting cells, connected to the sebaceous glands and the bulge region of the hair follicle anchors the stem cells. The nano lipid carriers have the propensity to penetrate through the skin via transcellular route, intracellular route and follicular route. It has been established that nano lipid carriers have the potential for follicular drug delivery and provide some advantages over conventional pathways, including improved bioavailability, enhanced penetration depth, fast transport into the skin, tissue targeting and form a drug reservoir for prolonged release. This review describes the pilosebaceous unit (PSU) and related diseases and the recent lipid-based nanotechnology approaches for drug delivery to the follicular unit as well as related issues. Different types of nano lipid carriers, including ethosomes, liposomes, nanoparticles, solid lipid nanoparticles (SLNs), and nano lipid carriers (NLCs) have been reported for follicular drug delivery. Targeted drug delivery with nano-lipid carriers has the potential to augment the efficacy of drugs/bioactives to treat diseases of PSU. This review systematically introduces the activities of different formulations and the use of nano lipid carriers in treating PSU related disorders like alopecia, acne, and hirsutism.


2020 ◽  
Vol 23 (10) ◽  
pp. 1064-1079
Author(s):  
Ahmet Alper Öztürk ◽  
İrem Namlı ◽  
Kadri Güleç ◽  
Şennur Görgülü

Aims: To prepare lamivudine (LAM)-loaded-nanoparticles (NPs) that can be used in lung cancer treatment. To change the antiviral indication of LAM to anticancer. Background: The development of anticancer drugs is a difficult process. One approach to accelerate the availability of drugs is to reclassify drugs approved for other conditions as anticancer. The most common route of administration of anticancer drugs is intravenous injection. Oral administration of anticancer drugs may considerably change current treatment modalities of chemotherapy and improve the life quality of cancer patients. There is also a potentially significant economic advantage. Objective: To characterize the LAM-loaded-NPs and examine the anticancer activity. Methods: LAM-loaded-NPs were prepared using Nano Spray-Dryer. Properties of NPs were elucidated by particle size (PS), polydispersity index (PDI), zeta potential (ZP), SEM, encapsulation efficiency (EE%), dissolution, release kinetics, DSC and FT-IR. Then, the anticancer activity of all NPs was examined. Results: The PS values of the LAM-loaded-NPs were between 373 and 486 nm. All NPs prepared have spherical structure and positive ZP. EE% was in a range of 61-79%. NPs showed prolonged release and the release kinetics fitted to the Weibull model. NPs structures were clarified by DSC and FT-IR analysis. The results showed that the properties of NPs were directly related to the drug:polymer ratio of feed solution. NPs have potential anticancer properties against A549 cell line at low concentrations and non-toxic to CCD 19-Lu cell line. Conclusion: NPs have potential anticancer properties against human lung adenocarcinoma cells and may induce cell death effectively and be a potent modality to treat this type of cancer. These experiments also indicate that our formulations are non-toxic to normal cells. It is clear that this study would bring a new perspective to cancer therapy.


Author(s):  
Gülsel Yurtdaş Kırımlıoğlu ◽  
Sinan Özer ◽  
Gülay Büyükköroğlu ◽  
Yasemin Yazan

Background: Considering the low ocular bioavailability of conventional formulations used for ocular bacterial infection treatment, there’s a need for designing efficient novel drug delivery systems that may enhance of precorneal retention time and corneal permeability. Aim and Objective: The current research focuses on developing nanosized and non-toxic Eudragit® RL 100 and Kollidon® SR nanoparticles loaded with moxifloxacin hydrochloride (MOX) for its prolonged release to be promising for effective ocular delivery. Methods: In this study, MOX was incorporation was carried out by spray drying method aiming ocular delivery. In vitro characteristics were evaluated in detail with different methods. Results: MOX was successfully incorporated into Eudragit® RL 100 and Kollidon® SR polymeric nanoparticles by spray-drying process. Particle size, zeta potential, entrapment efficiency, particle morphology, thermal, FTIR, XRD and NMR analyses and MOX quantification using HPLC method were carried out to evaluate the nanoparticles prepared. MOX loaded nanoparticles demonstrated nanosized and spherical shape while in vitro release studies demonstrated modified release pattern which followed Korsmeyer-Peppas kinetic model. Following successful incorporation of MOX into the nanoparticles, the formulation (MOX: Eudragit® RL 100, 1:5) (ERL-MOX 2) was selected for further studies by the reason of its better characteristics like cationic zeta potential, smaller particle size, narrow size distribution and more uniform prolonged release pattern. Moreover, ERL-MOX 2 formulation remained stable for 3 months and demonstrated higher cell viability values for MOX. Conclusion: In vitro characterization analyses showed that non-toxic, nano-sized and cationic ERLMOX 2 formulation has the potential of enhancing ocular bioavailability.


2013 ◽  
Vol 10 (3) ◽  
pp. 251-260 ◽  
Author(s):  
Francesco Cilurzo ◽  
Chiara G.M. Gennari ◽  
Francesca Selmin ◽  
Umberto M. Musazzi ◽  
Cristiano Rumio ◽  
...  
Keyword(s):  

2019 ◽  
Vol 16 (3) ◽  
pp. 347-352 ◽  
Author(s):  
M. Vlachou ◽  
G. Stavrou ◽  
A. Siamidi ◽  
S. Flitouri ◽  
V. Ioannidou ◽  
...  

Background: N-Acetylserotonin (NAS, N-acetyl-5-hydroxytryptamine) is the immediate precursor of the neurohormone melatonin (MT, N-acetyl-5-methoxytryptamine), which regulates sleep and wake cycles. NAS is produced by the N-acetylation of serotonin and is converted to melatonin via the action of Acetylserotonin O-methyltransferase (ASMT). Like melatonin, NAS acts as an agonist on the melatonin receptors MT1, MT2, and MT3. However, as NAS is abundant in specific brain areas, separate from serotonin and melatonin, it may also have discrete central effects. Indicatively, it has been reported that NAS may play a role in the antidepressant effects of Selective Serotonin Reuptake Inhibitors (SSRIs) and Monoamine Oxidase Inhibitors (MAOIs). </P><P> Objective: To decipher the controlled release characteristics of the active substances (NAS and MT) in a quick initial pace, aiming at a satisfactory sleep-onset related anti-depressive profile and prolonged release, thereafter, targeting at coping with poor sleep quality problems. </P><P> Methods: A series of hydrophilic matrix tablets involving as excipients, hydroxypropylmethylcellulose (HPMC) K15M, low viscosity sodium alginate, lactose monohydrate, and polyvinylpyrrolidone (PVP) M.W.: 10.000 and 55.000) was developed and tested at two dissolution media (pH 1.2 and 7.4). </P><P> Results: The results showed that commonly used excipients with different physicochemical properties govern the controlled release of NAS and MT from solid matrix systems. </P><P> Conclusions: We have demonstrated how broadly used excipients affect the in vitro controlled release of NAS and MT from solid pharmaceutical formulations. Currently, we extend our studies on the controlled release of these drugs using various other biopolymers/formulants of different physicochemical characteristics, which will help to highlight the discrete release profiles of NAS and MT.


2020 ◽  
Vol 12 ◽  
Author(s):  
Shivani Verma ◽  
Sukhjinder Kaur ◽  
Lalit Kumar

Background: HQ is used for hyper-pigmentation treatment using conventional creams and gels. These formulations show various disadvantages like poor skin permeation, allergic reactions, and repeated use decreasing patient compliance. Objectives: The present work involved formulation, statistical optimization, and characterization of nanostructured lipid carriers (NLCs) for efficient topical delivery of hydroquinone (HQ) for hyperpigmentation treatment. Methods: The NLCs were optimized exploring Box–Behnken design (BBD) using three independent variables and two dependent variables. Formulation having the minimum size and maximum drug entrapment was considered as optimized formulation. Optimized formulation was evaluated for drug release followed by its freeze-drying. The freeze-dried formulation was subjected to differential scanning calorimetry (DSC) analysis, X-raydiffraction (XRD) analysis, and Fourier transform-infrared spectroscopy (FT-IR) analysis. Furthermore, NLCs based gel was prepared by using Carbopol 934 as a gelling agent. NLCs based gel was evaluated for skin permeation, skin retention, and skin distribution (through confocal microscopic analysis) using pig ear skin. Results: Optimized NLCs showed smaller particle size [(271.9 ± 9) nm], high drug entrapment [(66.4 ± 1.2) %], tolerable polydispersity index (PDI) (0.221 ± 0.012), and zeta potential [(-25.9± 1.2) mV]. The FT-IR analysis revealed excellent compatibility between HQ and other excipients. The Carbopol 934 gel containing NLCs showed high transdermal flux [(163 ± 16.2) μg/cm2/h], permeability coefficient (0.0326 ± 0.0016), and skin permeation enhancement ratio (3.7 ± 0.4) compared to marketed cream of HQ. The results of confocal microscopic (CLSM) analysis revealed the accumulation of optimized NLCs in the lower epidermal layers of skin. Conclusion: NLCs based gel was considered effective in the topical delivery of HQ to treat hyper-pigmentation due high skin permeation, skin retention, and prolonged release of HQ.


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