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Melamine-impregnated paper is made by impregnating paper with melamine-formaldehyde resin and can be hot-pressed and laminated onto the surface of wood boards. If the paper has antibacterial activity, it can prevent the spread of indoor bacteria, but impregnated paper with a long-term antibacterial effect has not been proposed. Metal–organic frameworks (MOFs) have been studied as a reservoir of metal ions. In this study, a silver-metal organic framework (Ag-BTC) was synthesized by a green and scalable method at 60 °C (A-60) and at room temperature (A-25). The structure and thermal stability of the Ag-BTC were characterized. Compared with A-25, the structure and particle size distribution of A-60 were more regular and uniform. The thermal stability and the compatibility of Ag-BTC and MF resin were suitable for hot-pressing process. Ag-BTC in the cured impregnated paper exhibited the sustained-release performance of Ag+. The antibacterial ratio of decorated blockboards with 0.10 wt% A-25 to E. coli and S. aureus exceeded 99.99%, reaching Level I antibacterial grade. Compared with A-60-decorated blockboards, the better antibacterial activity of A-25-decorated blockboards was due to the release of more Ag+. This study provides new ideas for the design of antibacterial melamine-impregnated paper. [ABSTRACT FROM AUTHOR]

The introduction of long‐acting injectable buprenorphine preparations for opioid use disorder has been widely heralded as a breakthrough treatment, with several studies indicating positive results when using these medications. In many locations, nurse practitioners prescribe, administer, and monitor long‐acting injectable preparations. The objective of this paper is to explore whether a reduction in dispensed needles and syringes is attributable to increased nurse practitioner prescribing of LAIB. We used a retrospective audit of needles dispensed through the health service needle and syringe program vending machine, and individuals treated with long‐acting injectable buprenorphine by the nurse practitioner led model. In addition, we examined potential factors that may influence changes in the number of needles dispensed. Linear regression found that each individual with opioid dependence treated with long‐acting injectable buprenorphine was associated with 90 fewer needles dispensed each month (p < 0.001). The nurse practitioner led model of care for individuals with opioid dependence appears to have influenced the number of needles dispensed at the needle and syringe program. Although all confounding factors could not be discounted entirely, such as substance availability, affordability, and individuals obtaining injecting equipment elsewhere, our research indicates that a nurse practitioner led model of treating individuals with opioid use disorder influenced needle and syringe dispensing in the study setting. [ABSTRACT FROM AUTHOR]

Background and Aims: Long‐acting injectable buprenorphine (LAIB) is a new treatment for opioid use disorder that is generating positive outcomes. Negative effects are typically mild and transient, but can occasionally be serious, resulting in treatment discontinuation/non‐adherence. This paper aims to analyse patients' accounts of how they felt during the first 72 h after initiating LAIB. Methods: Semi‐structured interviews were conducted (June 2021–March 2022) with 26 people (18 males and 8 females) who had started LAIB within the previous 72 h. Participants were recruited from treatment services in England and Wales and were interviewed by telephone using a topic guide. Interviews were audio‐recorded, transcribed and coded. The concepts of embodiment and embodied cognition framed the analyses. Data on participants' substance use, initiation onto LAIB and feelings were tabulated. Next, participants' accounts of how they felt were analysed following the stages of Iterative Categorization. Results: Participants reported complex combinations of changing negative and positive feelings. Bodily experiences included withdrawal symptoms, poor sleep, injection‐site pain/soreness, lethargy and heightened senses inducing nausea ('distressed bodies'), but also enhanced somatic wellbeing, improved sleep, better skin, increased appetite, reduced constipation and heightened senses inducing pleasure ('returning body functions'). Cognitive responses included anxiety, uncertainties and low mood/depression ('the mind in crisis') and improved mood, greater positivity and reduced craving ('feeling psychologically better'). Whereas most negative effects reported are widely recognized, the early benefits of treatment described are less well‐documented and may be an overlooked distinctive feature of LAIB. Conclusions: During the first 72 h after initiating long‐acting injectable buprenorphine, new patients report experiencing a range of interconnected positive and negative short‐term effects. Providing new patients with information about the range and nature of these effects can prepare them for what to expect and help them manage feelings and reduce anxiety. In turn, this may increase medication adherence. [ABSTRACT FROM AUTHOR]

Developing long-acting products and formulations for infectious diseases is a nontrivial undertaking that is frequently classified as high risk and low reward by the pharmaceutical industry. The Long-Acting/Extended Release Antiretroviral Research Resource Program (LEAP) was founded in 2015 with the support of the National Institutes of Health to encourage, promote, and accelerate the development of such products. Assessment methodology for any new proposal brought to this group is part of a framework—the LEAP Process—that includes a landscape analysis of what is currently available in the public domain. This is followed by in silico modeling and simulation offered as a service to the relevant scientific community. A variety of preclinical and clinical outcome metrics are applied to each new agent as part of a continuous feedback loop to improve product characteristics. This allows us to catalog knowledge gaps and barriers that can be addressed by engaged stakeholders. Results are communicated in scientific articles, reviews, and position papers. This undertaking serves to de-risk discovery, development, and implementation by bridging the gaps between academic, regulatory, and industrial investigators, and by engaging those in the community who will be the eventual users of these medicines. The LEAP Process has supported formulations now approved for human immunodeficiency virus, as well as products in clinical and preclinical development for tuberculosis and hepatitis viruses B and C. [ABSTRACT FROM AUTHOR]

The objective of this paper was to develop a PLGA carrier Ticagrelor sustained-release microspheres preparation, which was expected to continue to release Ticagrelor for 14 days with a high encapsulation rate. Ticagrelor microspheres were prepared successfully with average diameter of 7.31 µm, drug loading of 12.49 ± 0.32% and EE up to 79.09 ± 1.69%. In the release medium of PH7.4 PBS, the microspheres showed good drug release behavior in vitro. In vivo release results also showed that the sustained-release microspheres could effectively control drug release in vivo and maintain a relatively stable blood drug concentration for about 2 weeks. The results indicate that Ticagrelor sustained-release microspheres can be used for long-term treatment of acute coronary syndrome. [ABSTRACT FROM AUTHOR]

Introduction: Qualitative analysis of Twitter posts reveals key insights about user norms, informedness, perceptions, and experiences related to opioid use disorder (OUD). This paper characterizes Twitter message content pertaining to medications for opioid use disorder (MOUD) and Naloxone. Methods: In-depth thematic analysis was conducted of 1,010 Twitter messages collected in June 2019. Our primary aim was to identify user perceptions and experiences related to harm reduction (e.g., Naloxone) and MOUD (e.g., sublingual and Extended-release buprenorphine, Extended-release naltrexone, Methadone). Results: Tweets relating to OUD were most commonly authored by general Twitter users (43.8%), private residential or detoxification programs (24.6%), healthcare providers (e.g., physicians, first responders; 4.3%), PWUOs (4.7%) and their caregivers (2.9%). Naloxone was mentioned in 23.8% of posts and authored most commonly by general users (52.9%), public health experts (7.4%), and nonprofit/advocacy organizations (6.6%). Sentiment was mostly positive about Naloxone (73.6%). Commonly mentioned MOUDs in our search consisted of Buprenorphine-naloxone (13.8%), Methadone (5.7%), Extended-release naltrexone (4.1%), and Extended-release buprenorphine (0.01%). Tweets authored by PWUOs (4.7%) most commonly related to factors influencing access to MOUD or adverse events related to MOUD (70.8%), negative or positive experiences with illicit substance use (25%), policies related to expanding access to treatments for OUD (8.3%), and stigma experienced by healthcare providers (8.3%). Conclusion: Twitter is utilized by a diverse array of individuals, including PWUOs, and offers an innovative approach to evaluate experiences and themes related to illicit opioid use, MOUD, and harm reduction. [ABSTRACT FROM AUTHOR]

Background: Targetable drug delivery is an important method for the treatment of liver tumors. For the quantitative analysis of drug diffusion, the establishment of a method for information collection and characterization of extracellular space is developed by imaging analysis of magnetic resonance imaging (MRI) sequences. In this paper, we smoothed out interferential part in scanned digital MRI images.Materials and Methods: Making full use of priors of low rank, nonlocal self-similarity, and regularized sparsity-promoting entropy, a block-matching regularized entropy minimization algorithm is proposed. Sparsity-promoting entropy function produces much sparser representation of grouped nonlocal similar blocks of image by solving a nonconvex minimization problem. Moreover, an alternating direction method of multipliers algorithm is proposed to iteratively solve the problem above.Results and Conclusions: Experiments on simulated and real images reveal that the proposed method obtains better image restorations compared with some state-of-the-art methods, where most information is recovered and few artifacts are produced. [ABSTRACT FROM AUTHOR]

The efficacy of traditional tablets, drop pills and soft capsules of bergenin is far lower than expected. Therefore, bergenin was modified in this paper to connect with amino polylactic acid, a kind of biodegradable material, for chemical immobilization. The bergenin-amino PLA thus obtained was controllable with small molecular weight and excellent thermal stability. Its release in vitro could be extended with the increase in molecular weight. According to tests of biological compatibility and anti-tumor in vitro, bergenin-amino PLA at a proportion of 1 to 100 was characterized by better biological compatibility and lower cytotoxicity than control group at a concentration of 0.4 μ g/m L. The chemical immobilization of bergenin not only provides patients with an excellent way of drug administration but lays a good foundation for sustained drug release. Unlabelled Image [ABSTRACT FROM AUTHOR]

Controlled release packaging (CRP) is an innovative technology that uses the package to release active compounds in a controlled manner to improve safety and quality for a wide range of food products during storage. This paper provides a critical review of the uniqueness, design considerations, and research gaps of CRP, with a focus on the kinetics and mechanism of active compounds releasing from the package. Literature data and practical examples are presented to illustrate how CRP controls what active compounds to release, when and how to release, how much and how fast to release, in order to improve food safety and quality. [ABSTRACT FROM AUTHOR]

Objectives: Women with sickle cell disease (SCD) are living longer as a result of advances in the care of their underlying disease. With the population growing of women living with SCD, reproductive health issues in this population have become an emphasized area of medical care. We sought to describe current patterns of contraception use, menstruation, and quality-of-life (QOL) measures in women with SCD.Methods: Using a cross-sectional study design, we administered paper surveys at two academic medical centers to women aged 10 to 55 years with SCD to capture current contraceptive use, characteristics of menstrual cycles, and QOL metrics.Results: Of the 103 women who participated, 12.7% (13/102) experienced a duration of menses >7 days (defined here as prolonged menstrual bleeding). Approximately half of women (51.5%, 53/103) used some form of contraception, with depot medroxyprogesterone acetate injections and condoms being the most common. During their last menstrual periods, women with both dysmenorrhea and prolonged menstrual bleeding (6.9%, 7/102) were more likely to experience more days of poor QOL, with more nights with sleep disturbance (P = 0.001) and more days with trouble taking care of themselves (P = 0.003), as well as being unable to do things they previously enjoyed (P = 0.001), compared with those with neither phenomenon (28.2%, 29/103).Conclusions: Dysmenorrhea and prolonged menstrual bleeding negatively affect the QOL of women with SCD. Menstrual histories and preventive measures for menstruation-related morbidity should be incorporated into routine evaluations of women with SCD. [ABSTRACT FROM AUTHOR]

Postoperative infection and thromboembolism represent significant sources of morbidity and mortality but cannot be easily tracked after hospital discharge. Therefore, a molecular test that could be performed at home would significantly impact disease management. The laboratory has previously developed intravenously delivered 'synthetic biomarkers' that respond to dysregulated proteases to produce a urinary signal. These assays, however, have been limited to chronic diseases or acute diseases initiated at the time of diagnostic administration. Here, a subcutaneously administered sustained-release system, using small poly(ethylene glycol) scaffolds (<10 nm) to promote diffusion into the bloodstream over a day, is formulated. The utility of a thrombin sensor to identify thrombosis and an Matrix metalloproteinase (MMP) sensor to measure inflammation is demonstrated. Finally, a companion paper ELISA (Enzyme-linked immunosorbent sssay), using printed wax barriers, with nanomolar sensitivity for urinary reporters for point-of-care detection is developed. The approach for subcutaneous delivery of nanosensors combined with urinary paper analysis may enable facile monitoring of at-risk patients. [ABSTRACT FROM AUTHOR]

Abstract: Aims: To review systematically the published literature on extended‐release naltrexone (XR‐NTX, Vivitrol®), marketed as a once‐per‐month injection product to treat opioid use disorder. We addressed the following questions: (1) how successful is induction on XR‐NTX; (2) what are adherence rates to XR‐NTX; and (3) does XR‐NTX decrease opioid use? Factors associated with these outcomes as well as overdose rates were examined. Methods: We searched PubMed and used Google Scholar for forward citation searches of peer‐reviewed papers from January 2006 to June 2017. Studies that included individuals seeking treatment for opioid use disorder who were offered XR‐NTX were included. Results: We identified and included 34 studies. Pooled estimates showed that XR‐NTX induction success was lower in studies that included individuals that required opioid detoxification [62.6%, 95% confidence interval (CI) = 54.5–70.0%] compared with studies that included individuals already detoxified from opioids (85.0%, 95% CI = 78.0–90.1%); 44.2% (95% CI = 33.1–55.9%) of individuals took all scheduled injections of XR‐NTX, which were usually six or fewer. Adherence was higher in prospective investigational studies (i.e. studies conducted in a research context according to a study protocol) compared to retrospective studies of medical records taken from routine care (6‐month rates: 46.7%, 95% CI = 34.5–59.2% versus 10.5%, 95% CI = 4.6–22.4%, respectively). Compared with referral to treatment, XR‐NTX reduced opioid use in adults under criminal justice supervision and when administered to inmates before release. XR‐NTX reduced opioid use compared with placebo in Russian adults, but this effect was confounded by differential retention between study groups. XR‐NTX showed similar efficacy to buprenorphine when randomization occurred after detoxification, but was inferior to buprenorphine when randomization occurred prior to detoxification. Conclusions: Many individuals intending to start extended‐release naltrexone (XR‐NTX) do not and most who do start XR‐NTX discontinue treatment prematurely, two factors that limit its clinical utility significantly. XR‐NTX appears to decrease opioid use but there are few experimental demonstrations of this effect. [ABSTRACT FROM AUTHOR]

Objective: Paliperidone palmitate is now available as a three-month depot injection. This paper will review the pharmacokinetics, pharmacodynamics, efficacy and tolerability, as well as practical issues and pitfalls for clinicians with this innovative treatment for schizophrenia.Conclusion: The three-month depot formulation of paliperidone for the treatment of schizophrenia is not a new compound. The nanocrystalline structure of the three-month formulation is larger and takes longer to disperse than the one-month formulation, hence its extended depot action. As expected, it is non-inferior to one-month depot paliperidone, and superior to placebo, for the treatment of schizophrenia. The side effect profile of three-month paliperidone is identical to the one-month formulation. The relapse rate on treatment is low, and the median time to relapse after ceasing the drug is 395 days. An understanding of half-life and kinetics is crucial for clinicians using this compound, and the loading strategy is important to ensure effectiveness. There are significant challenges: ensuring timely administration and switching a three-month depot treatment to another antipsychotic may be problematic. Paliperidone palmitate three-month depot injection represents an advance for both convenience and effectiveness in the long term psychopharmacological treatment of schizophrenia. [ABSTRACT FROM AUTHOR]

In this paper, lignin-polyurea microcapsules (LPMC) with anti-photolysis and sustained-release performance were synthesized by interfacial polymerization based on Pickering emulsion templates of lignin particle-stabilized oil-in-water (O/W). Scanning electron microscopy (SEM) and optical microscopy (OM) images showed that LPMC was spherical in shape, with a double layer structure of a loose outer layer and a dense inner layer and its mean diameter was 10–100 μm. Fourier transform infrared spectroscopy (FTIR) indicated that lignin had successfully participated in the interfacial polymerization of polyurea. LPMC were used to encapsulate avermectin (AVM), a kind of photosensitive pesticide. According to the experiment results of sustained release and anti-photolysis performance, the AVM cumulative release amount of AVM@lignin-polyurea microcapsules (AVM@LPMC) was 85% more than that of AVM@polyurea microcapsules (AVM@PMC) 50% after 72 h. And the effective AVM retention rate of AVM@LPMC reached as high as 72%, while that of AVM@PMC was only 30% under UV radiation for 120 h. [ABSTRACT FROM AUTHOR]

Paliperidone palmitate 3-month formulation (PP3M), a long-acting injectable atypical antipsychotic, was recently approved in the US and Europe for the treatment of schizophrenia in adult patients who have already been treated with paliperidone palmitate 1-month formulation (PP1M) for ≥4 months. This article reviews the pharmacokinetic rationale for the approved dosing regimens for PP3M, dosing windows, management of missed doses and treatment discontinuation, switching to other formulations, and dosing in special populations. Approved PP3M dosing regimens are based on the comparisons of simulations with predefined dosing regimens using paliperidone palmitate and oral paliperidone extended release (ER) population pharmacokinetic models (one-compartment model with two saturable absorption processes for PP3M; one-compartment model with parallel zero- and first-order absorption for PP1M; two-compartment model with sequential zero- and first-order absorption for ER) versus clinical trial data. Covariates were obtained by resampling subject covariates from the pharmacokinetics database for PP1M and PP3M. Simulation scenarios with varying doses and covariate values were generated. The population median and 90% prediction interval of the simulated concentration-time profiles were plotted for simulation outcomes evaluation. Simulations described in this paper provide (a) simulated plasma exposures for switching from PP1M to PP3M, (b) support for a once-every-3-months injection cycle, (c) information on dosing windows and managing missed doses of PP3M, (d) important guidance on PP3M dosing in special patient populations, and (e) key PP3M pharmacokinetic exposure metrics based on the population pharmacokinetic PP3M model. Population pharmacokinetics provided practical guidance to establish dosing regimens for PP3M. [ABSTRACT FROM AUTHOR]

This paper addressed the application of hydroxyethyl pachyman (HEP) as a novel matrix for sustained – release tablets, using diclofenac sodium (DS) as a model drug. The studies showed the HEP tablets prepared by wet granulation had much slower drug release as compared to those prepared by direct compression. Meanwhile, increasing the percentage of HEP in the formulations caused a decrease in drug release rates. Moreover, DS release from the HEP tablets was much higher at high pH (6.8) than that at low pH (1.2). Morphology studies proved the HEP tablet formed a continuous gel layer with porous inner structure in the dissolution media. Analysis of DS release profiles revealed that diffusion and matrix erosion occurred in simulated intestinal fluid(SIF, pH = 6.8) for all the tablets. The experimental results predict HEP has a potential as a hydrophilic matrix in tablets to prolong drug release. [ABSTRACT FROM AUTHOR]

Controlled release is an important determinant of the in-vivo performance of drug delivering nanoparticles (NPs). Therefore the control over and understanding of the release mechanism, e . g . by disassembly or degradation of the carrier, is essential for the optimization of NP formulations. This paper presents a supramolecular toolbox approach for the formation and UV-induced disassembly of supramolecular nanoparticles (SNPs) which are either exclusively stabilized by cucurbit[8]uril (CB[8])/methyl viologen (MV)/azobenzene (Azo) interactions or CB[8]/MV/naphthol (Np) interactions, or by a combination of both. Photoisomerization of the Azo units enables UV-triggered disassembly of the CB[8]/MV/Azo host-guest complex. Depending on the valency of the electron-rich guest moieties (Np or Azo), either SNPs with a UV-responsive shell or a UV-responsive core were formed by assembling SNPs using a mixture of Azo and Np bearing guest molecules. In contrast, non-responsive SNPs or SNPs which disintegrate at both the core and the shell were formed by using exclusively CB[8]/MV/Np or CB[8]/MV/Azo interactions, respectively. [ABSTRACT FROM AUTHOR]

To improve the recognition ability and the controlled release of andrographolide (ADR), it is necessary to prepare a better intelligent drug delivery carrier. In this paper, the magnetic andrographolide imprinted polymer (ADR-MMIP) with pH/redox/light triple stimulus response was successfully prepared by reverse atom transfer radical polymerization (RATRP), where ADR was as the template, β-Cyclodextrin (β-CD) and 4-amino-4′-methacrylamide azobenzene (AMAB) as the bi-functional monomers, and both of N, N′-bis (acryloyl) cystamine (BAC) and ethylene glycol dimethacrylate (EGDMA) as cross-linkers. A series of adsorption experiments indicated that ADR-MMIP had excellent adsorption and selectivity capacities with the maximum adsorption capacity 41.43 mg g−1 and the factors α 4.256 and β 1.940 for the selectivity and relative selectivity, respectively. The adsorption mechanism of ADR-MMIP was investigated the multiphase adsorption with the chemical action on heterogeneous material surface by the linear fitting with the isothermal and kinetic adsorption models, and the in-vitro ADR release showed ADR-MMIP was sensitive to the triple-stimuli of pH/redox/light with the maximum cumulative drug release rate 91.53% when the above three conditions were applied concurrently. The above information demonstrated the ADR-MMIP should be of great application potential in the ADR extraction and isolation from mixture and the intelligent drug delivery system. [Display omitted] • A new magnetic andrographolide molecularly imprinted polymer (ADR-MMIP) was prepared by RATRP technology; • The ADR-MMIP could achieve physical targeting by using external magnetic field for active remote guidance; • The ADR-MMIP had the high selectivity and adsorption capacity on andrographolide; • This imprinted material had the good stability and reproducibility; • In vitro release studies indicated that ADR-MMIP could controllably release ADR via triple pH/redox/light-sensitive bonds. [ABSTRACT FROM AUTHOR]

The release profile of chlorhexidine from the PerioChip™ (Chip), a biodegradable local delivery system that contains 2.5 mg of chlorhexidine gluconate (CHX) in a cross-linked hydrolyzed gelatin matrix, into the gingival crevice, was evaluated in an in vivo, open label, single-center. 10-day pharmaco-kinetic study conducted on 19 volunteers with chronic adult periodontitis. Each volunteer had a single chip inserted into each of 4 selected pockets, with probing pocket depths of between 5-8 mm, at time 0. Gingival crevicular fluid (GCF) samples were collected using filter paper strips prior to Chip placement and at 2 h, 4 h, 24 h and 2, 3, 4, 5, 6, 8, and 9 days post-Chip placement. The GCF volume was measured using a calibrated Periotron™ 6000. Blood samples were collected at times 0, 1, 4, 8, 12 h and 5 days post-dosing. Urine was collected as a total 24-h specimen immediately post-dosing and 2 single samples at time 0, prior to dosing, and 5 days. The CHX was eluted from the paper strips and the CHX levels in GCF, blood and urine quantified using HPLC. The results indicate an initial peak concentration of CHX in the GCF at 2 h post-Chip insertion (2007 μg/ml) with slightly lower concentrations of between 1300-1900 μg/ml being maintained over the next 96 h. The CHX concentration then progressively decreased until study conclusion with significant CHX concentrations (mean = 57 μg/ml) still being detectable at study termination. CHX was not detectable in any of the plasma or urine samples at any time point during the study. These results indicate that the PerioChip™ can maintain clinically effective levels of CHX in the GCF of periodontal pockets for over 1 week with no detectable systemic absorption. [ABSTRACT FROM AUTHOR]

Therapeutic proteins and peptides demonstrate unique, peerless, pharmacological characteristics such as high specificity to receptors and superior biological mimicking of physiological mechanisms, resulting in a better therapeutic index compared to conventional chemical-derived drugs. However, proteins also present inherent bioavailability limitations. Thus, this paper proposes several effective tools to improve protein/peptide drugs stability, permeability and pharmacokinetics with special emphasis on oral polymeric films as oral delivery platforms. Indeed, oral films present inherent characteristics that can greatly enhance biological performance of proteins and peptides and patient compliance along with other advantages that are critically discussed in this review. A rational choice of excipients addressed in and manufacture processes are also focused. In addition, possible toxicity issues to be overtaken and critical analysis regarding current market tendencies respecting oral films and protein/peptides along with future prospects are disclosed. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this paper was to introduce a new mechanism of thermal sensitivity in nanocarriers that results in a relatively low drug release at physiological temperature and rapid release of the encapsulated drug at hyperthermia and thermal ablation temperature range (40-60 °C). Materials and methods: The nanocarriers were synthesised by coating mesoporous silica nanoparticles with a thin layer of polyacrylamide. The low gelation temperature of the protective shell provides preferred routes for drug diffusion when the nanocarriers are heated within the hyperthermia temperature range. In order to determine the gelation point of polyacrylamide shell, differential scanning calorimetry was used. Various chemical, morphological, thermal, as well as drug loading capacities of these nanocarriers were characterised and their drug release behaviour was examined using magnetic resonance -guided focused ultrasound (MRgFUS). Results: Drug release measurements at different temperatures using doxorubicin showed 11.5 ± 2.4% leakage in aqueous solution at 37 °C after 30 min, while this value was significantly increased to 67.6 ± 2.5% at 60 °C. A 39.2 ± 2.2% release of doxorubicin was also obtained due to the sonication of drug-loaded nanoparticles for 5 × 20 s using MRgFUS. Conclusion: The nanocarriers developed do not exhibit a sharp transition temperature. However, a relatively high loading efficiency as well as rapid drug release at thermal ablation temperature range makes these nanostructures promising candidates for application as adjuvants to various thermal modalities such as radiofrequency and high intensity focused ultrasound. [ABSTRACT FROM AUTHOR]

PAI-1 prevents lysis of blood clot by inhibiting the urokinase and tPA induced conversion of plasminogen to plasmin. VLHL PAI-1 protein mutant was created to extend half-life over 700 hours. The objective of this paper was to test VLHL PAI-1 effects on bleeding during partial nephrectomy in mice. All animals had a left partial nephrectomy after intravenous infusion of saline or tPA. The animals were divided into four groups. Group 1 was infused with saline and kidney was exposed to saline too; Group 2 was infused with saline and kidney was exposed to PAI-1. Group 3 was infused with tPA and kidney was exposed to saline, while Group 4 was infused with tPA and kidney was exposed to PAI-1. Preweighed gauze containing PAI-1 or saline was then applied to the kidney for 30 minutes. The gauze was afterward weighed and blood loss was measured by subtracting the preweight of gauze from the final weight. We have observed a statistically significant (P≤0.05) reduction of bleeding in PAI-1-treated group in comparison to saline and tPA-treated groups. Based on these results we propose that VLHL PAI-1 can be used therapeutically in limiting the flow of blood from renal wounds. [ABSTRACT FROM AUTHOR]

Purpose -- This paper aims to study the controlled release and synergistic effect of water-soluble polyvinyl alcohol (PVA) on phosphate corrosion inhibitor at the interface of thermal insulation cotton/carbon steel. Design/methodology/approach -- This study was carried out using a coating method, scanning electron microscopy, energy dispersive spectroscopy and AC impedance. Findings -- The single-phase phosphate particles were coated/adsorbed on the PVA film, which was formed on the fiber surface of corrosion inhibitor/PVA-impregnated rock wool sample. On the surface of Q235 steel, an effective protective film was formed by the corrosion inhibitor with partially dissolved PVA that can significantly increase the polarization resistance of corrosion reaction, and reduce the capacitive reactance of electric double layer. The rock wool impregnated with the phosphate corrosion inhibitor and 1.5 per cent PVA showed obvious controlled release and inhibition synergism. Originality/value -- The rock wool impregnated with the phosphate corrosion inhibitor and 1.5 per cent PVA showed the following advantages: the adsorption and release quantities of the corrosion inhibitor increased by 3.3 and 2.9 times, respectively; the release-adsorption equilibrium time increased from 2 to 6 h; and the corrosion inhibition efficiency increased from 61.55 per cent to 94.6 per cent. [ABSTRACT FROM AUTHOR]

In this paper, ascorbic acid (Vitamin C, AA) known as an antioxidant was successfully incorporated in solid lipid nanoparticles (SLNs) by hot homogenization and efficient delivery of AA to cancer cells. The obtained SLN formulations were characterized by Nano Zetasizer ZS and HPLC with the particle size being less than 250 nm. AA-SLNs exhibited sustained release and high entrapment efficiency. According to MTT test results, AA-SLNs showed high cytotoxic activity compared to the free AA against H-Ras 5RP7 cells without damaging NIH/3T3 control cells. These results were supported by the Annexin V-PI and caspase-3 assay. Furthermore, as compared to the AA, AA-SLNs exhibited more efficient cellular uptake, accumulated in the cytoplasm and induced apoptosis which was observed by confocal laser scanning microscopy (CLSM) and transmission electron microscopy (TEM). Thus, the results of this study suggest that SLNs can be a potential nanocarrier system for AA. [ABSTRACT FROM AUTHOR]

Lignin is the most abundant renewable aromatic resource on the Earth, which can be used for producing bio-products to support human sustainable development. Due to the dual challenges of resources and environment, how to effectively utilize this kind of abundant, degradable, and renewable natural polymer has attracted great attention. In recent years, there are many studies on lignin-based slow-release fertilizer duo to its excellent slow release properties. As a carrier of nutrients, lignin-based physically impeded fertilizer can be realized by absorbing and wrapping nutrients, and lignin-based chemically modified fertilizer can be realized by chemical reaction between lignin and nutrients. In this paper, we reviewed the application of lignin in preparation of slow-release fertilizer. The possible pathways and release mechanisms of physically impeded and chemically modified slow-release fertilizer were discussed. Although there was no uniform evaluation standard for slow-release fertilizer, its three common evaluation criteria were analyzed. With the expansion of the function of slow-release fertilizer, the evaluation system should be broadened and diversified. Finally, the challenges and future prospects of lignin-based slow-release fertilizer were discussed. The application of lignin-based slow-release fertilizer has great potential for promoting resource utilization and environmental protection. [Display omitted] • Lignin is an excellent carrier of nutrients for slow-release fertilizer. • Ammoxidation, Mannich, chelation are primarily chemical modification method. • The possible release mechanisms of slow-release fertilizer were explored. • The evaluation of lignin-based slow-release fertilizer was analyzed. • Challenge and future prospect of lignin-based slow-release fertilizer was assessed. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the effects of hydrogel mesh size, a conductive polymer, and electric field strength on controlled drug delivery phenomena using drug-loaded polyacrylamide hydrogels prepared at various crosslinking ratios both with and without a conductive polymer system. Poly(p-phenylene vinylene), PPV, as the model conductive polymer, was used to study its ability to control aloin released from aloin-doped poly(p-phenylene vinylene)/polyacrylamide hydrogel (aloin-doped PPV/PAAM). In the passive release, the diffusion of aloin from five aloin-doped PPV/PAAM hydrogel systems each was delayed ranging from during the first three hours to during the first 14 h due to the ionic interaction between the anionic drug and PPV. After the delayed periods, aloin could diffuse continuously into the buffer solution through the PAAM matrix. The amount of aloin released from the aloin-doped PPV/PAAM rose with increasing electric field strength as a result of the three mechanisms: the expansion of PPV chains inside the hydrogel, iontophoresis, and the electroporation of the matrix pore size, combined. Furthermore, the conductive polymer and the electric field could be used in combination to regulate the amount of release drug to a desired level, to control the release rate, and to switch the drug delivery on/off. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the controlled release of aroma compounds from cyclodextrins (CDs) and CD polymers was studied by multiple headspace extraction (MHE) experiments. Mentha piperita essential oil was obtained by Soxhlet extraction and identification of the major compounds was performed by GC–MS analysis. Menthol, menthone, pulegone and eucalyptol were identified as the major components. Retention of standard compounds in the presence of different CDs and CD polymers has been realised by static headspace gas chromatography (SH-GC) at 25°C in the aqueous or gaseous phase. Stability constants for standard compounds and for compounds in essential oil have been also determined with monomeric CD derivatives. The obtained results indicated the formation of a 1:1 inclusion complex for all the studied compounds. Molecular modelling was used to investigate the complementarities between host and guest. This study showed that β-CDs were the most versatile CDs and that β-CD polymers could perform the controlled release of aroma compounds. [Copyright &y& Elsevier]

Aim: The current paper was an attempt to design a sustained release dosage form using various grades of hydrophilic polymers, Hypromellose (hydroxyl-propyl methylcellulose [HPMC] K15M, HPMC K100M and HPMC K200M) and Polyacrylate polymers, Eudragit RL100 and Eudragit RS100 with or without incorporating ethyl cellulose on a matrix-controlled drug delivery system of Metformin hydrochloride. Materials and Methods: Laboratory scale batches of nine tablet formulations were prepared by wet granulation technique (Low shear). Micromeritic properties of the granules were evaluated prior to compression. Tablets were characterized as crushing strength, friability, weight variation, thickness, drug content or assay and evaluated for in-vitro release pattern for 12 h using Phosphate buffer of pH 6.8 at 37± 0.5°C. The in-vitro release mechanism was evaluated by kinetic modeling. Results and Discussion: The results obtained revealed that HPMC K200M at a concentration of 26% in formulation (F6) was able to sustain the drug release for 12 h and followed the Higuchi pattern quasi-Fickian diffusion. With that, combined effect of HPMC K15M as an extragranular section and Eudragit RS100 displayed a significant role in drug release. Dissolution data were compared with innovator for similarity factor (f2), and exhibited an acceptable value of ≥50 Three production validation scale batches were designed based on lab scale best batch and charged for stability testing, parameters were within the limit of acceptance. There was no chemical interaction found between the drug and excipients during Fourier Transform Infrared Spectroscopy (FTIR) and Differential scanning calorimetry study. Conclusion: Hence, combinely HPMC K200M and Eudragit RS100 at a suitable concentration can effectively be used to sustain drug release. [ABSTRACT FROM AUTHOR]

Abstract: In this paper it is shown that when a thermosensitive hydrogel based on poly(N-isopropylacrylamide)-poly(ethylene glycol)-poly(N-isopropylacrylamide) (pNIPAm-PEG-pNIPAm) was transferred into water, flower-like micelles were continuously released as long as the medium was regularly refreshed. On the other hand, if the medium was not refreshed the concentration of micelles reached an equilibrium. When this gel was loaded with the cytostatic agent paclitaxel (PTX), the released micelles solubilized PTX, as evidenced by a PTX concentration in the release medium above its aqueous solubility. To test the applicability of these micelle-releasing gels for sustained and systemic delivery of PTX an in vivo experiment was performed in tumor-bearing mice. pNIPAm-PEG-pNIPAm gels (without and with 1.2% and 6.0% PTX loading) were administered i.p. in nude mice bearing 14C human squamous cell carcinoma tumor xenografts to obtain doses corresponding to one and five times the maximum tolerated dose of PTX (when given i.v. as the standard formulation in Cremophor EL/ethanol). All gel formulations were well tolerated and no signs of acute systemic toxicity were observed. After injection of the highest dose, PTX levels in serum could be determined for 48h with a comparatively long elimination half-life of 7.4h pointing to a sustained release of PTX. A bioavailability of 100% was calculated from the area under the curve of plasma concentration vs time. Furthermore, at the highest dose, PTX was shown to completely inhibit tumor growth for at least 3weeks with a single hydrogel injection. This promising concept may find application as a depot formulation for sustained, metronomic dosing of chemotherapeutics. [Copyright &y& Elsevier]

Abstract: It is difficult to develop injectable sustained delivery systems for herbal medicines because of their composition complexity. Encapsulating various compounds with different physiochemical properties and achieving their synchronized and sustained release seem too hard to realize. In this paper, an injectable nanoparticulate system based on an mPEG–PLGA–mPEG (PELGE) platform was prepared for co-encapsulation and sustained release of four active components (ginkgolides A, B, C and bilobalide) in Ginkgo biloba extract. Different carriers were screened by macrophage uptake experiment for their ability to be long-circulation. Drug loaded nanoparticles were prepared with 10% PEG2000 modified PLGA by a co-precipitation method. The encapsulation efficiency of the total ginkgo terpenes (GT) in the optimal formulation was 78.84±2.06% with a loading dose of 11.90±0.31mg/150mg PELGE. The particles exhibited a spherical shape with a mean diameter of 123.3±44.0nm and zeta potential of −30.86±2.49mV. Sustained and synchronized release of the four components from PELGE nanoparticles was observed both in vitro and in vivo, which was mainly contributed to the long circulation of PEGylated nanoparticles and the slow degradation of PLGA. The half-life time of the four terpenoid compounds were also significantly improved by incorporation into PELGE nanoparticles. The results indicate that a PELGE nanoparticle is a promising carrier system for sustained and synchronized release of herbal medicines containing multiple components. [Copyright &y& Elsevier]

Abstract: Evidence from literature has shown that compared with instant addition, slow release of antioxidants has some advantages to inhibit lipid oxidation and extend shelf life of food products. In this paper, the hypothesis that there is a range of release rates of antioxidants which could provide the maximum extension of induction period for lipid oxidation was tested in a model system using a syringe pump to deliver tocopherol into linoleic acid. Conjugated dienes, the first products appearing in lipid oxidation, were measured to determine the length of induction period for onset of lipid oxidation during incubation at 30 and 40°C. Maximum inhibition of oxidation occurred at the release rates of 3.3×10−4 and 7.7×10−4 g/day at 30 and 40°C, respectively, supporting the hypothesis. Based on the results, a term “target release rate” was defined and its application in controlled release packaging was discussed. [Copyright &y& Elsevier]

Natural polymers, because of their biocompatibility, availability, and physico-chemical properties have been the materials of choice for the fabrication of injectable hydrogels for regenerative medicine. In particular, they are appealing materials for delivery systems and provide sustained and controlled release of drugs, proteins, gene, cells, and other active biomolecules immobilized. In this work, the use of hydrogels obtained from natural source polymers as cell delivery systems is discussed. These materials were investigated for the repair of cartilage, bone, adipose tissue, intervertebral disc, neural, and cardiac tissue. Papers from the last ten years were considered, with a particular focus on the advances of the last five years. A critical discussion is centered on new perspectives and challenges in the regeneration of specific tissues, with the aim of highlighting the limits of current systems and possible future advancements. [ABSTRACT FROM AUTHOR]

Controlled release of additives and adhesives at the right place and the right time is a key functionality that can be provided by microencapsulation technology. A timely and targeted release improves the effectiveness of additives and adhesives, broadens their application range, and ensures optimal dosage, thereby improving cost-effectiveness for the adhesive manufacturer. Reactive, sensitive, or volatile additives (catalysts, prepolymers, solvents, antioxidants, preservatives, adhesion promoters, biocides, flame retardants, dyes, etc), as well as the total formulation of the adhesive, can be turned into stable ones through microencapsulation. With carefully fine-tuned controlled release properties, microencapsulation is no longer just an added value technique, but the source of totally new products with matchless properties. Nevertheless, although it offers great potential in the adhesive and sealants industry, very little development has been carried out to date in this field. Therefore, the aim of the present literature review paper is to present microencapsulation technique as an interesting option for the adhesive industry as its application can transform traditionally used adhesives into smart or multifunctional ones. [ABSTRACT FROM PUBLISHER]

Abstract: This paper reports the effective treatment of Schistosoma japonicum in a mouse model with long-acting praziquantel (PZQ)-loaded poly(ε-caprolactone) implants. The implants yielded stable, high plasma PZQ concentrations ranging 100–1600ng/mL during the 40-day investigation period. For assessment of efficacy, the implants were implanted into mice immediately after infection and at 1, 2, 3 and 4weeks after infection to treat the schistosomes at different developmental stages. All the mice were sacrificed at 6weeks after infection for worm and egg recovery, worm morphology examination, and histopathological analysis of implantation site tissues. The worm burdens, egg burdens, and numbers of miracidia hatched from the retrieved eggs for all the implant-treated groups (except groups T2-A, T4 and T5) were reduced by 100% when compared with the control group. From groups T2-A, T4 and T5, some schistosome debris was recovered. Eggs were found in only group T5 for which the time between infection and implantation was 4weeks, which enabled the maturation of juvenile female schistosomes into adult ones that lay eggs. Histopathological observations of implantation tissue showed no evidence of granulomatous foreign-body or lymphoid cell aggregation, demonstrating good biocompatibility of the PZQ implants. These results demonstrate that the long-acting PZQ implants can kill schistosomes at any developmental stages and attenuate/avoid the associated liver damage. [Copyright &y& Elsevier]

This paper describes the synthesis of thermosensitive surfactants by polymerizing N-isopropylacrylamide (NIPAAm) into the Pluronic F68 surfactant and their application for a controlled drug release. Poly(NIPAAm)-Pluronic surfactants with different lengths of the NIPAAm block were synthesized by activating two hydroxyl groups of poly(ethylene oxide) (PEO) at the end of Pluronic F68 using cerium ammonium nitrate (CAN, redox initiator), followed by adding the NIPAAm monomer into a reactor. The resultant poly(NIPAAm)-Pluronic surfactants were characterized by FT-IR and gel filtration chromatography (GPC). It was observed that their critical micellar concentrations increased with an increase in the length of the poly(NIPAAm) block. In addition, poly(D, L-lactide-co-glycolide) (PLGA) microparticles was prepared by an oil-in-water emulsion and solvent evaporation method using the poly(NIPAAm)-Pluronic surfactants in an aqueous continuous phase. At 37°C, nile red (model dye) was released from the PLGA microparticles in a more sustained manner when the length of poly(NIPAAm) was longer due to a thicker layer of shrunken poly(NIPAAm) at the surface of the microparticles. [ABSTRACT FROM AUTHOR]

Background: Modified-release (MR) products are complex dosage forms designed to release drug in a controlled manner to achieve the desired efficacy and safety profiles. Inappropriate control of drug release from such products may result in reduced efficacy or increased toxicity. Objective: This paper is a summary report of the American Association of Pharmaceutical Scientists, International Pharmaceutical Federation, and Product Quality Research Institute workshop titled “Challenges and Opportunities in Establishing Scientific and Regulatory Standards for Assuring Therapeutic Equivalence of Modified Release Products”, held October 1–2, 2009, in Baltimore, Maryland. Methods: The workshop provided an opportunity for pharmaceutical scientists from academia, industry, and regulatory agencies to discuss current regulatory expectations and industry practices for evaluating the pharmaceutical equivalence and bioequivalence of oral MR products. Results: In the case of conventional monophasic MR formulations, the current regulatory approaches and criteria for bioequivalence evaluation were considered adequate for the assessment of therapeutic equivalence and inter-changeability of drug products. Additional measures may occasionally be needed to determine the bioequivalence of multiphasic MR products. The metric of partial AUC proposed by the US Food and Drug Administration received broad support as an additional measure for evaluating bioequivalence of multiphasic MR products designed to have a rapid onset of drug action followed by sustained response. The cutoff for partial AUCs may be based on the pharmacokinetic/pharmacodynamic or pharmacokinetic/ response characteristics of the products under examination. If the new metric is highly variable, the bioequivalence limits may be set based on the known within-subject vari- ability for the reference product. Conclusions: The current regulatory approaches and criteria for bioequivalence evaluation were considered adequate for the assessment of therapeutic equivalence and interchangeability of conventional monophasic MR products. Additional measures may occasionally be needed to establish the bioequivalence of multiphasic MR products, and development of such measures is an important objective. The metric of partial AUC was proposed for products designed to have a rapid drug action followed by sustained response. [Copyright &y& Elsevier]

Abstract: In this paper, two charge-neutral and poorly water-soluble bactericides (BC), hexaconazole and triadimenol, were first encapsulated in micelles derived from anionic surfactant, calcium dodecylbenzenesulfonate (DBS), and then were successfully intercalated into the gallery of Mg–Al layered double hydroxides (LDHs) by using ion exchange, coprecipitation and reconstruction methods, respectively, to obtain BC–LDHs nanohybrids. The loading amounts of hexaconazole-LDHs nanohybrids are obviously higher than those of triadimenol-LDHs nanohybrids. The release kinetics of bactericides from the nanohybrids was investigated. It was found that the bactericide release kinetic processes of the nanohybrids can be described with pseudo-second-order model. The initial release rates and equilibrium percent releases of the nanohybrids are obviously dependent of synthesis methods. The nanohybrids can well control the release of bactericides, showing they are a potential pesticide controlled-release formulation. [Copyright &y& Elsevier]

In order to lower the risks associated to intensive pesticide use, efforts have been made at the European and the national level of several member countries of the European Union. In Germany, a national reduction programme for pesticides had been set up. The programme makes use of the methods elaborated in the context of the NEPTUN-project. The NEPTUN-approach had introduced several indicators to assess the intensity of pesticide use in agriculture. This approach was exemplarily applied to data from a case study region in north-eastern Germany. The aim of the paper is to discuss the strengths and weaknesses of the presented approach as based on results gained in the chosen case study region. [Copyright &y& Elsevier]

Abstract: This paper reports the preparation and characterization of sustained release sodium diclofenac microparticles by spray drying. Aqueous dispersions of ethyl cellulose (Surelease®) and Eudragit RS 30 D® were evaluated as controlled release polymers. The product properties (product moisture, size distribution, particle morphology, flow properties, total drug load, in-vitro dissolution studies, and encapsulating efficiency) were determined as a function of inlet temperature of the spray drying, the feed flow rate and composition of the microencapsulating formulation. In general, lower values of the product moisture content were observed at higher drying temperatures. The spray-dried product was composed mainly by rounded-shape and multi-size particles. The mean particle diameters of the Eudragit based microparticles tended to be slight bigger than the Surelease based microparticles. The spray dried microparticles showed delayed drug dissolution rates, sustaining the drug release for several hours. These findings confirm the feasibility of the spray drying for preparation of microparticles with sustained release properties. The physical and chemical properties of the microparticles can be changed by varying the spray drying parameters as well as the microencapsulating formulation. [Copyright &y& Elsevier]

In this paper, we present a preclinical approach for evaluating the feasibility of applying controlled-release (CR) oral drug delivery to increase the duration of exposure and lower the Cmax of compounds in a lead series of short half-life atypical antipsychotics. Three lead compounds in the series had demonstrated potential pharmacological benefits for the treatment of psychosis, in preclinical studies. However, the compounds showed evidence of insufficient half-lives to enable a once-a-day (QD) product using immediate-release (IR) oral delivery. To evaluate and compare the potential for oral CR delivery to extend the duration of action and thereby enable QD administration, the in vitro solubility and permeability, and the duodenal and colonic absorption of three compounds in the series were measured. Based on the results, one candidate was selected for advancement that showed moderate in vitro solubility, but had the highest in vitro permeability and ratio of colonic to duodenal bioavailability (0.9) in the rat. The results from this study provided evidence that a CR drug delivery system could be used to extend the duration of exposure of the compounds in the series and a scientific basis for selecting one of the three compounds as a candidate. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95:883–895, 2006 [ABSTRACT FROM AUTHOR]

Abstract: Cellular delivery involving the transfer of various drugs and bio-active molecules (peptides, proteins and DNAs, etc.) through the cell membrane into cells has attracted increasing attention because of its importance in medicine and drug delivery. This topic has been extensively reviewed. The direct delivery of drugs and biomolecules, however, is generally inefficient and suffering from problems such as enzymic degradation of DNAs. Therefore, searching for efficient and safe transport vehicles (carriers) to delivery genes or drugs into cells has been challenging yet exciting area of research. In past decades, many carriers have been developed and investigated extensively which can be generally classified into four major groups: viral carriers, organic cationic compounds, recombinant protiens and inorganic nanoparticles. Many inorganic materials, such as calcium phosphate, gold, carbon materials, silicon oxide, iron oxide and layered double hydroxide (LDH), have been studied. Inorganic nanoparticles show low toxicity and promise for controlled delivery properties, thus presenting a new alternative to viral carriers and cationic carriers. Inorganic nanoparticles generally possess versatile properties suitable for cellular delivery, including wide availability, rich functionality, good biocompatibility, potential capability of targeted delivery (e.g. selectively destroying cancer cells but sparing normal tissues) and controlled release of carried drugs. This paper reviews the latest advances in inorganic nanoparticle applications as cellular delivery carriers and highlights some key issues in efficient cellular delivery using inorganic nanoparticles. Critical properties of inorganic nanoparticles, surface functionalisation (modification), uptake of biomolecules, the driving forces for delivery, and release of biomolecules will be reviewed systematically. Selected examples of promising inorganic nanoparticle delivery systems, including gold, fullerences and carbon nanotubes, LDH and various oxide nanoparticles in particular their applications for gene delivery will be discussed. The fundamental understanding of properties of inorganic nanoparticles in relation to cellular delivery efficiency as the most paramount issue will be highlighted. [Copyright &y& Elsevier]

Abstract: Increasing the solubility in aqueous environment while alleviating the toxicity of the delivery system at the same time are the vital challenges related to the administration of the antitumor drugs. In the present paper we describe a novel drug delivery system for the well known anticancer drug, camptothecin (CPT). This system is the aggregates of O-carboxymethylchitosan (OCMCS), which is a kind of biocompatible and amphiphilic chitosan derivative. The amount of drug loaded was examined by stead-state fluorescence. The release behaviors of CPT from this proposed controlled release system in PBS solution at 37°C were studied by UV spectroscopy. The antiproliferative activity of cancer cell was evaluated using MTS assay. The results demonstrate that not only the aggregates but also the unimers of OCMCS can help to enhance the solubility of CPT. After CPT is loaded in OCMCS, the release of CPT is significantly sustained, which is caused by the interactions between OCMCS and lipophilic CPT. In vitro cancer antiproliferative activity test further confirms the slow release of CPT from OCMCS-drug system. The result of OCMCS unimers showing as good drug-loading and controlled release capability as its aggregates indicates that this novel release system can solve the commonly existing problem of unavailability of micelles assembled from amphiphilic copolymer in the significant dilution accompanying IV injection. These findings propose a new concept of a localized drug delivery. [Copyright &y& Elsevier]

This paper reports the properties of vitamin C encapsulated sodium alginate beads prepared by an alternative approach. The alternative encapsulation process mainly involves immobilization of vitamin C in hydrated zinc oxide layers and encapsulation of prepared immobilized particles in sodium alginate bead. The immobilization of vitamin C in hydrated zinc oxide layers was achieved by a coprecipitation process. Fourier transform infrared (FTIR) spectroscopy showed that the vitamin C was found to be stable after its immobilization. X-ray diffraction (XRD) studies revealed that anionic vitamin C molecules are adsorbed between positively charged zinc hydroxide layers with a 1:1 layer sequence, since well-defined change in basal spacing was observed. Well-defined change in surface morphology was observed by scanning electron microscopy (SEM) when vitamin C immobilized particles are encapsulated in sodium alginate bead. The biological activity of vitamin C was retained, even after its immobilization which was confirmed by 4-dihydroxy-L-phenylalanine (L-DOPA) oxidase inhibition and free radical scavenging activity studies. The release rate of vitamin C from immobilized particles and beads was sustained through an ion exchange process. A higher amount of stable vitamin C was recovered from the bead when compared to neat vitamin C itself. [ABSTRACT FROM AUTHOR]

Chronoflex, a polyurethane, is a suitable material for use in polymeric tracheobronchial stents. A controlled release layer on the stent is required for effective localized delivery of cancer drugs to the tumor cells. This paper reports on the investigation of coating Chronoflex with acrylated oligomers by argon plasma assisted UV graft polymerization. Coatings of poly(ethylene glycol) diacrylate (PEGDA) with molecular weight 700 or a 50 : 50 mixture of PEGDA with poly(propylene glycol) diacrylate (PPGDA) with molecular weight 900 which were tens of micrometers thick were shown to have good adhesion to Chronoflex. No photoinitiator was added. Formulations containing photoinitiator or a trifunctional crosslinker which increases strength and decreases water swelling showed poor adhesion to Chronoflex. The degree of water swelling of grafted PEGDA coating reached about 709%, making it suitable for use as a hydrogel coating for controlled drug release on Chronoflex. Adding PPGDA to PEGDA was shown to decrease the degree of water swelling. Hence, removal of the photoinitiator, use of oligomeric diacrylate with high molecular weight per acrylate group and a clean Chronoflex surface are found to be important factors for ensuring adhesion between the thick hydrogel coating and Chronoflex. [ABSTRACT FROM AUTHOR]

In this paper, different electromigration methods used to monitor drugs and polymers released from drug delivery systems are reviewed. First, an introduction to the most typical arrangements used as drug delivery systems (e.g., polymer–drug covalent conjugates, membrane or matrix-based devices) is presented. Next, the principles of different capillary electromigration procedures are discussed, followed by a revision on the different procedures employed to monitor the release of drugs and the degradation or solubilization of the polymeric matrices from drug delivery systems during both in vitro and in vivo assays. A critical comparison between these capillary electrophoretic methods and the more common chromatographic methods employed to analyze drugs and polymers from drug delivery systems is presented. Finally, future outlooks of these electromigration procedures in the controlled release field are discussed. [Copyright &y& Elsevier]

There are many similarities between the human health and animal health industries. Both industries are research driven, have global presence, are highly regulated, and have to profit in a competitive business environment. However, there are also notable differences. This review highlights and discusses those differences as they relate to the pharmaceutical challenges in veterinary product development. This paper provides a brief review of the animal health pharmaceutical product landscape, segmentation, and market evolution; highlights challenges and special considerations in veterinary drug delivery; and identifies unmet needs in animal health along with recent advances. [Copyright &y& Elsevier]

This paper, a continuation of our previous work, is a presentation of the effect of the morphology and the average thickness of the deformed coating films on the slow diffusional release characteristics analyzed numerically under the constraints of the constant volume of the drug matrices and the coating films, if the films have the same average thickness. Increasing the average thickness of the coating films slows down the fractional release and the average release rate of the drug and smoothen the initial burst of the drug, as well as increase the initial lag time. The effect due to deformation of the coating films on these diffusional release characteristics are found to be less significant with the increasing average thickness of the coating films. Interestingly initial lag times are found to be the same for the coated particles having the same smallest thickness but different average thickness of coating films. The effect due to the change in the average thickness of the coating films on the characteristics of the slow controlled-release is discussed to shed light on the design of a better controlled-release device. [Copyright &y& Elsevier]

• Preparation of sustained-release microcapsules containing calcium chloride. • Reduce the salting-out effect of calcium chloride on lauryl sulfate solution. • Extend fire prevention and suppression time of water-based foam. To reduce the effect of conventional halogen salt inhibitors on the performance of foaming solutions and extend the fire prevention and suppression time of water-based foams, herein, microencapsulation technology has been used in the preparation of inhibitors. Calcium chloride sustained-release microcapsule with ethyl cellulose as wall material was successfully prepared by solvent evaporation method. The microcapsule complied with Higuchi release kinetics equation. The experiment showed that the foaming solution added with 20 g microcapsules had almost the same foaming capacity as the pure foaming solution, and the foaming multiple could reach 14 times, and the half-life of the foam could reach 123 min. The foaming multiple was much higher than the foaming multiple of calcium chloride foam (0 times). Compared with calcium chloride foam, the new type of foam prepared in this paper has better inhibition ability, and the inhibition rate is as high as 83.8%. Ethyl cellulose used as wall material in microcapsules can soften covered coal in the process of heating up, isolate coal and oxygen, and thus inhibit coal and oxygen binding. The experimental results show that the temperature of T1 (84.6℃), T3 (338.2℃) and the cross-point temperatures of the coal sample treated with the new type of foam are higher than that of the coal sample treated with the calcium chloride foam. At the same time, the new type of foam can significantly inhibit the oxidation rate of methyl and methylene. It can be seen that the microencapsulation technology can improve the ability of the inhibitor foam. [ABSTRACT FROM AUTHOR]