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Within the scope of the European Horizon 2020 project ACDC – Artificial Cells with Distributed Cores to Decipher Protein Function, we aim at the development of a chemical compiler governing the three-dimensional arrangement of droplets, which are filled with various chemicals. Neighboring droplets form bilayers containing pores through which chemicals can move from one droplet to its neighbors. When achieving a desired three-dimensional configuration of droplets, we can thus enable gradual biochemical reaction schemes for various purposes, e.g., for the production of some desired macromolecules for pharmaceutical purposes. In this paper, we focus on geometric restrictions to possible arrangements of droplets. We present analytic results for the buttercup problem and a heuristic optimization method for the kissing number problem, which we then apply to find (quasi) optimum values for a bidisperse kissing number problem, in which the center sphere exhibits a larger radius.

We aim at planning and creating specific agglomerations of droplets to study synergic communication using these as programmable units. In this paper, we give an overview of preliminary obstacles for the various research issues, namely of how to create droplets, how to set up droplet agglomerations using DNA technology, how to prepare them for confocal microscopy, how to make a computer see droplets on photos, how to analyze networks of droplets, how to perform simulations mimicking experiments, and how to plan specific agglomerations of droplets.

We simulate the movement and agglomeration of oil droplets in water under constraints, like confinement, using a simplified stochastic-hydrodynamic model. In the analysis of the network created by the droplets in the agglomeration, we focus on the paths between pairs of droplets and compare the computational results for various system sizes.

Within the context of the European Horizon 2020 project ACDC, we intend to develop a probabilistic chemical compiler, to aid the construction of three-dimensional agglomerations of artificial hierarchical cellular constructs. These programmable discrete units offer a wide variety of technical innovations, like a portable biochemical laboratory that e.g. produces macromolecular medicine on demand. For this purpose, we have to investigate the agglomeration process of droplets and vesicles under proposed constraints, like confinement. This paper focuses on the influence of the geometry of the initialization and of the container on the agglomeration.

Anticancer drug development is a crucial step toward cancer treatment, that requires realistic predictions of malignant tissue development and sophisticated drug delivery. Tumors often acquire drug resistance and drug efficacy, hence cannot be accurately predicted in 2D tumor cell cultures. On the other hand, 3D cultures, including multicellular tumor spheroids (MCTSs), mimic the in vivo cellular arrangement and provide robust platforms for drug testing when grown in hydrogels with characteristics similar to the living body. Microparticles and liposomes are considered smart drug delivery vehicles, are able to target cancerous tissue, and can release entrapped drugs on demand. Microfluidics serve as a high‐throughput tool for reproducible, flexible, and automated production of droplet‐based microscale constructs, tailored to the desired final application. In this review, it is described how natural hydrogels in combination with droplet microfluidics can generate MCTSs, and the use of microfluidics to produce tumor targeting microparticles and liposomes. One of the highlights of the review documents the use of the bottom‐up construction methodologies of synthetic biology for the formation of artificial cellular assemblies, which may additionally incorporate both target cancer cells and prospective drug candidates, as an integrated “droplet incubator” drug assay platform., This review summarizes the recent progress of droplet technologies in anticancer drug development. Microfluidic‐formed droplets are utilized in both tumor spheroid formation and smart drug delivery. This work also highlights the current trend of using artificial cells materials for drug metabolism studies. Finally, a novel ‘droplet incubator’ concept as a prospective anticancer drug screening platform is introduced.

The bottom‐up construction of synthetic cells with user‐defined chemical organization holds considerable promise in the creation of bioinspired materials. Complex emulsions, droplet networks, and nested vesicles all represent platforms for the engineering of segregated chemistries with controlled communication, analogous to biological cells. Microfluidic manufacture of such droplet‐based materials typically results in radial or axisymmetric structures. In contrast, biological cells frequently display chemical polarity or gradients, which enable the determination of directionality, and inform higher‐order interactions. Here, a dual‐material, 3D‐printing methodology to produce microfluidic architectures that enable the construction of functional, asymmetric, hierarchical, emulsion‐based artificial cellular chassis is developed. These materials incorporate droplet networks, lipid membranes, and nanoparticle components. Microfluidic 3D‐channel arrangements enable symmetry‐breaking and the spatial patterning of droplet hierarchies. This approach can produce internal gradients and hemispherically patterned, multilayered shells alongside chemical compartmentalization. Such organization enables incorporation of organic and inorganic components, including lipid bilayers, within the same entity. In this way, functional polarization, that imparts individual and collective directionality on the resulting artificial cells, is demonstrated. This approach enables exploitation of polarity and asymmetry, in conjunction with compartmentalized and networked chemistry, in single and higher‐order organized structures, thereby increasing the palette of functionality in artificial cellular materials., Polarized artificial cells are created by 3D‐microfluidics. Multi‐material 3D‐printed microfluidics is used to create hierarchical droplet assemblies, where 3D‐channel geometries enable asymmetric and polarized patterning in droplet assemblies. These materials contain lipid‐bilayer‐segregated droplet networks and integrate patterned organic and inorganic components. Polarized patterning with magnetic microparticles bestows directional properties and motion in aqueous environments, with constructs exhibiting simple group‐level behaviors.

In article number https://doi.org/10.1002/advs.201901719, David Anthony Barrow, Oliver Kieran Castell, and co‐workers create polarized artificial cells from compartmentalized droplet networks and nanomaterials, using multi‐material, 3D‐printed fluidics. Polarized patterning with magnetic microparticles bestow directional properties and motion in aqueous environments, with artificial cells exhibiting simple group‐level behaviors.

PURPOSE: Obesity may alter mononuclear phagocyte system (MPS) function and the pharmacology and efficacy of nanoparticles therapies, such as PEGylated liposomal doxorubicin (PLD). We aimed to evaluate relationships between hormone and chemokine mediators of MPS function and the pharmacokinetic (PK) exposure of PLD in obese and normal weight patients with ovarian and endometrial cancer. METHODS: Hormone and chemokine mediators in obese and normal weight ovarian and endometrial cancer patients were measured. A separate pharmacology study was performed that evaluated the relationship between serum hormone concentrations, MPS function, and PK disposition of PLD in refractory ovarian cancer patients. RESULTS: Univariate analysis revealed a significant relationship between serum estradiol and body mass index (OR: 8.64, 95% CI: 2.67–28.0, p

Summary Objective Our study analyzes the association between chemokine-ligand-2 (CCL2) serum concentrations at baseline and knee radiographic osteoarthritis (OA) (knee-rOA), knee-rOA progression, individual radiographic features and knee symptomatic OA at 5-year follow-up. Design OA outcomes were analyzed in a community-based cohort including a baseline enrollment and a 5-year follow-up. Baseline CCL2 serum concentrations were assessed by multiplex assay and associated with presence or progression of individual radiographic features at 5-year follow-up. Separate multiple logistic regression models were used to examine adjusted associations between baseline CCL2 and each of the knee OA variables at follow-up. CCL2 at baseline was modeled as an explanatory variable, whereas each of the knee OA variables at follow-up served as the response variables. Models were adjusted for age, BMI, race, and sex. Trend tests were conducted to assess any linear effect on outcomes across CCL2 tertiles. Results Participants (n = 168) had a median age of 57-years and median BMI of 29 kg/m2. About 63% of all participants were women, and 58% Caucasian (42% African American). In adjusted logistic models, continuous log-CCL2 was significantly associated with knee-rOA. For each unit increase in log CCL2, the odds of having knee-rOA at follow-up was increased by 72%. CCL2 tertiles showed significant linear associations with presence and progression of knee-rOA and medial joint space narrowing (JSN), but not with presence or progression of osteophytes, bone sclerosis, knee symptoms, or symptomatic knee-rOA. Conclusions Serum CCL2 may help to elucidate some mechanisms of joint destruction and identify individuals with higher odds of structural knee changes.

Objective To determine whether dietary interventions that increase n-3 fatty acids with and without reduction in n-6 linoleic acid can alter circulating lipid mediators implicated in headache pathogenesis, and decrease headache in adults with migraine. Design Three arm, parallel group, randomized, modified double blind, controlled trial. Setting Ambulatory, academic medical center in the United States over 16 weeks. Participants 182 participants (88% women, mean age 38 years) with migraines on 5-20 days per month (67% met criteria for chronic migraine). Interventions Three diets designed with eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and linoleic acid altered as controlled variables: H3 diet (n=61)—increase EPA+DHA to 1.5 g/day and maintain linoleic acid at around 7% of energy; H3-L6 diet (n=61)—increase n-3 EPA+DHA to 1.5 g/day and decrease linoleic acid to ≤1.8% of energy; control diet (n=60)—maintain EPA+DHA at Main outcome measures The primary endpoints (week 16) were the antinociceptive mediator 17-hydroxydocosahexaenoic acid (17-HDHA) in blood and the headache impact test (HIT-6), a six item questionnaire assessing headache impact on quality of life. Headache frequency was assessed daily with an electronic diary. Results In intention-to-treat analyses (n=182), the H3-L6 and H3 diets increased circulating 17-HDHA (log ng/mL) compared with the control diet (baseline-adjusted mean difference 0.6, 95% confidence interval 0.2 to 0.9; 0.7, 0.4 to 1.1, respectively). The observed improvement in HIT-6 scores in the H3-L6 and H3 groups was not statistically significant (−1.6, −4.2 to 1.0, and −1.5, −4.2 to 1.2, respectively). Compared with the control diet, the H3-L6 and H3 diets decreased total headache hours per day (−1.7, −2.5 to −0.9, and −1.3, −2.1 to −0.5, respectively), moderate to severe headache hours per day (−0.8, −1.2 to −0.4, and −0.7, −1.1 to −0.3, respectively), and headache days per month (−4.0, −5.2 to −2.7, and −2.0, −3.3 to −0.7, respectively). The H3-L6 diet decreased headache days per month more than the H3 diet (−2.0, −3.2 to −0.8), suggesting additional benefit from lowering dietary linoleic acid. The H3-L6 and H3 diets altered n-3 and n-6 fatty acids and several of their nociceptive oxylipin derivatives in plasma, serum, erythrocytes or immune cells, but did not alter classic headache mediators calcitonin gene related peptide and prostaglandin E2. Conclusions The H3-L6 and H3 interventions altered bioactive mediators implicated in headache pathogenesis and decreased frequency and severity of headaches, but did not significantly improve quality of life. Trial registration ClinicalTrials.gov NCT02012790

The ability to make artificial lipid bilayers compatible with a wide range of environments, and with sufficient structural rigidity for manual handling, would open up a wealth of opportunities for their more routine use in real‐world applications. Although droplet interface bilayers (DIBs) have been demonstrated in a host of laboratory applications, from chemical logic to biosynthesis reaction vessels, their wider use is hampered by a lack of mechanical stability and the largely manual methods employed in their production. Multiphase microfluidics has enabled us to construct hierarchical triple emulsions with a semipermeable shell, in order to form robust, bilayer‐bound, droplet networks capable of communication with their external surroundings. These constructs are stable in air, water, and oil environments and overcome a critical obstacle of achieving structural rigidity without compromising environmental interaction. This paves the way for practical application of artificial membranes or droplet networks in diverse areas such as medical applications, drug testing, biophysical studies and their use as synthetic cells.

Computerized tomography scan (CT scan) imaging and finite element analysis were employed to investigate how the geometric composition of microneedles affects their mechanical strength and penetration characteristics. Simulations of microneedle arrays, comprising triangular, square and hexagonal microneedle base, revealed a linear dependence of the mechanical strength to the number of vertices in the polygon base. A laser-enabled, micromoulding technique was then used to fabricate 3 × 3 microneedle arrays, each individual microneedle having triangular, square or hexagonal base geometries. Their penetration characteristics into ex-vivo porcine skin, were investigated for the first time by CT scan imaging. This revealed greater penetration depths for the triangular and square-based microneedles, demonstrating CT scan as a powerful and reliable technique for studying microneedle skin penetration.

Microneedle technology offers a viable means of delivering biologically active pharmaceutical agents across the skin in a minimally invasive and virtually pain free manner. Previous work detailed the first successful transdermal delivery of a model peptide drug, polymyxin b, utilising a dissolving polymer-based microneedle system. The focus of this study was to examine the ability of a dissolving microneedle system to deliver a range of peptides of different sizes and properties. Analogue versions of 2 existing therapeutic peptides; pentagastrin and sincalide, were synthesised utilising Fmoc based solid phase peptide synthesis (SPPS) chemistry techniques and once successfully synthesised and purified, the peptide analogues were characterised using LC-MS. The peptide analogues were then incorporated into PVP/trehalose microneedle formulations. Skin permeation testing, in addition to skin penetration testing, was carried out to determine the effectiveness of the microneedle system to deliver the peptide analogues through porcine skin. The results obtained from these studies were then compared with the permeation results obtained utilising polymyxin B as the peptide drug cargo to evaluate the PVP/trehalose microneedle system's suitability to successfully deliver therapeutic peptides. Results indicated that the microneedle system successfully systemically delivered a higher overall percentage of the encapsulated peptides at an initially faster rate than peptide loaded control discs and in therapeutically relevant concentrations.

Background Serum levels of pro-inflammatory cytokines tend to be increased in irritable bowel syndrome (IBS) patients, or subgroups thereof. Still, the link between cytokine levels and IBS symptoms is unclear. We aim to determine systemic cytokine levels in IBS patients and healthy subjects (HS), confirm the presence of a subset of patients with an increased immune activity and to establish if cytokines are linked to IBS symptoms and pathophysiological factors. Methods Serum levels of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF), and IL-10 were measured. All subjects reported IBS symptoms using validated questionnaires and underwent colonic sensorimotor testing. Multivariate supervised orthogonal partial least squares-discriminant analysis (OPLS-DA) and unsupervised principal component analysis (PCA) and hierarchical cluster analysis (HCA) were implemented. Key results Irritable bowel syndrome patients (n = 246) had higher serum levels of IL-1β, IL-6, IL-8, TNF, and IL-10 compared to HS (n = 21); however, serum cytokine profiles could not discriminate patients from HS. Moreover, cytokine levels were not correlated with symptoms among patients. Supervised OPLS-DA identified 104 patients (40% of patients) and unsupervised HCA analysis identified 49 patients (20%) with an increased immune activity indicated by elevated levels of serum cytokines compared to HS and the other patients. However, irrespective of how patients with increased immune activity were identified they were symptomatically similar to patients with no indication of increased immune activity. Conclusions & inferences Serum cytokines are elevated in IBS patients compared to HS. Immune activation characterizes a subset of patients, but modest associations between cytokine profile and symptoms suggest immune activity does not directly influence symptoms in IBS.

Nanoparticles (NPs) are cleared by monocytes and macrophages. Chemokines CCL2 and CCL5 are key mediators for recruitment of these immune cells into tumors and tissues. The purpose of this study was to investigate effects of CCL2 and CCL5 on the pharmacokinetics (PKs) of NPs. Mice deficient in CCL2 or CCL5 demonstrated altered clearance and tissue distribution of polyethylene glycol tagged liposomal doxorubicin (PLD) compared to control mice. The PK studies using mice bearing SKOV3 ovarian cancer xenografts revealed that the presence of tumor cells and higher expression of chemokines were significantly associated with greater clearance of PLD compared to non-tumor bearing mice. Plasma exposure of encapsulated liposomal doxorubicin positively correlated with the total exposure of plasma CCL2 and CCL5 in patients with recurrent epithelial ovarian cancer treated with PLD. These data emphasize that the interplay between PLD and chemokines may have an important role in optimizing PLD therapy. From the Clinical Editor The use of nanoparticles as drug delivery carriers is gaining widespread acceptance in the clinical setting. However, the underlying pharmacokinetics of these novel drugs has not really been elucidated. In this interesting article, the authors carried out experiments using mice deficient in CCL2 or CCL5 to study the clearance of liposomal system. They showed the important role the immune system played and would enable better designs of future drug delivery systems.

In this paper, a new type of microwave microfluidic sensor is proposed to detect and determine the dielectric properties of common liquids. The technique is based on perturbation theory, in which the resonant frequency and quality factor of the microwave resonator depend on the dielectric properties of the resonator. A microstrip split-ring resonator with two gaps is adopted for the design of the sensors (i.e., a double split-ring resonator). This resonator is both compact and planar, making it suitable for a lab-on-a-chip approach. Several types of solvents are tested with two types of capillaries to verify sensor performance. At 3 GHz, very good agreement is demonstrated between simulated and measured results.

We present a method of making low-loss split-ring resonators (SRRs) for microfluidic sensing at microwave frequencies using silver-coated copper wire. We show that a simple geometric modification and the use of square cross-section wire give greater electric field confinement in the capacitive region of the resonant sensor. We use a combination of theoretical analysis, finite-element simulations, and empirical measurements to demonstrate the subsequent increases in the sensitivity of these SRRs for complex permittivity measurements of some common solvents.

Aim Investigate short-term effects of power brushing following experimental induction of biofilm overgrowth in periodontal disease states. Materials and Methods Overall, 175 subjects representing each of five biofilm–gingival interface (BGI) periodontal groups were enrolled in a single-blind, randomized study. After stent-induced biofilm overgrowth for 21 days subjects received either a manual or a power toothbrush to use during a 4 weeks resolution phase. At baseline and during induction and resolution, standard clinical parameters were measured. Subclinical parameters included multikine analysis of 13 salivary biomarkers and 16s Human Oral Microbe Identification Microarray (HOMIM) probe analysis of subgingival plaque samples. Results All groups exhibited significantly greater reductions in bleeding on probing (BOP) (p = 0.002), gingival index (GI) (p = 0.0007), pocket depth (PD) (p = 0.04) and plaque index (p = 0.001) with power brushing compared to manual. When BGI groups were combined to form a shallow PD (PD ≤ 3 mm) and a deep PD group (PD > 4 mm) power brushing reduced BOP and GI in subjects with both pocket depths. Power brushing significantly reduced IL-1β levels at resolution while changes in bacterial levels showed non-significant trends between both brushing modalities. Conclusions Short-term changes in select clinical parameters and subclinical salivary biomarkers may be useful in assessing efficacy of power brushing interventions in a spectrum of periodontal disease states.

This paper presents a 2.45 GHz microwave cavity resonator with the novel dual function of both sensitive dielectric characterisation and directed, volumetric heating of fluids in a microfluidic chip. This method is shown to have a higher efficiency (> 90% for methanol) than previous microfluidic microwave heating methods and can regulate heating using real time cavity characterisation. The system is simple, robust and does not require on-chip integration of microwave waveguide structures. Furthermore, this method can be combined with miniaturised resonators (such as split rings) for localisation of heating within a microfluidic chip.

Herein, we demonstrate a method for simultaneously quantifying the electric and magnetic properties of liquid systems confined within a capillary. This is based upon an optimized perturbation of a microwave-frequency coaxial resonator, chosen to maximize the spatial separation of the two fields and to minimize the depolarization of the liquid. A capillary is passed through the center of the resonator so the sample occupies either maximum electric field (zero magnetic field) or maximum magnetic field (zero electric field) depending on whether an odd or even TEM mode is interrogated. This allows electric and magnetic effects to be distinguished at multiple discrete frequencies. We demonstrate this capability through the quantification of varying ionic content of saline solutions, which interact with both the electric and magnetic fields via several polarization mechanisms. The distinction of different cations and anions is also demonstrated.

A novel microfluidic biosensing platform based on Bipolar-Complementary Oxide Semiconductor (BiCMOS) technology is presented. The device relies on a quadruple electrode system and a microfluidic channel that are directly integrated into the back-end-of-line (BEOL) of the BiCMOS stack. For proof of concept repeatable electrical trapping of single SW620 (colon cancer) cells in the quadruple electrode system is initially demonstrated. Additionally, for the first time a microwave intermodulation technique is used for high sensitivity dielectric spectroscopy, which could pave the way to label-free monitoring of intracellular processes and manipulation such as electroporation.

Purpose Multifactorial etiological factors contribute to denture stomatitis (DS), a type of oral candidiasis; however, unlike other oral candidiasis, DS can occur in a healthy person wearing a denture. In this study, we therefore attempt to explore the association between candida, denture, and mucosal tissue using 1) exfoliative cytology, 2) the candidal levels present in saliva, on mucosal tissues and on denture surfaces, and 3) the salivary flow rate and xerostomic symptoms.

A device for analysing the chemical composition of single- and multi-phase solvent flows using microfluidic dielectric spectroscopy is demonstrated in this work. An open-circuited, half-wavelength, coaxial resonator operating at microwave frequencies (i.e. harmonics of 600 MHz) was embedded in a compression-sealed polytetrafluoroethylene microfluidic chip for in situ characterization of solvent–solvent and solute–solvent mixtures of varying concentration, and an aqueous–organic segmented flow. Results are shown for a solvent mixture of acetonitrile in toluene as a test system, exhibiting a sensitivity limit of 400 nM. In addition to being highly sensitive, the measurement system is fast, robust and non-invasive, and can be readily miniaturized.

Herein we present a technique for performing complex permittivity measurements with an overmoded, evanescently perturbed coaxial resonator at microwave frequencies. The design of a noninvasive electromagnetic coupling structure, which allows transmission measurements to be taken from one end of a resonant section of coaxial cable, is discussed in detail. Quasi-spectral information was obtained through the exploitation of higher order resonances, and complex permittivity measurements of a number of common industrial solvents were taken at multiple discrete frequencies between 1 and 8 GHz. A combination of experimental and simulated results was used also to characterise the device behavior. The high stability of temporal measurements, coupled with the robustness of the design, make this device ideal for analytical chemistry and industrial process control.

Delivering apoptosis inducing peptides to cells is an emerging area in cancer and molecular therapeutics. Here, we have identified an alternative mechanism of action for the proapoptotic chimeric peptide D-NuBCP-9-r8. Integral to D-NuBCP-9-r8 is the Nur-77-derived D-isoform sequence fsrslhsll that targets Bcl-2, and the cell-penetrating peptide (CPP) octaarginine (r8) that is required for intracellular delivery. We find that the N-terminal phenylalanine of fsrslhsll acts in synergy with the cell-penetrating moiety to enhance peptide uptake at low nontoxic levels and cause rapid membrane blebbing and cell necrosis at higher (IC(50)) concentrations. These effects were not observed when a single phenylalanine-alanine mutation was introduced at the N-terminus of D-NuBCP-9-r8. Using primary samples from chronic lymphocytic leukemia (CLL) patients and cancer cell lines, we show that NuBCP-9-r8 induced toxicity, via membrane disruption, is independent of Bcl-2 expression. Overall, this study demonstrates a new mechanism of action for this peptide and cautions its use as a highly specific entity for targeting Bcl-2. For delivery of therapeutic peptides the work emphasizes that key amino acids in cargo, located several residues away from the cell-penetrating sequence, can significantly influence their cellular uptake and mode of action.

A contributing factor to the labored advance of molecularly imprinting as a viable commercial solution to molecular recognition needs is the absence of a standard and robust method for assessing and reporting on molecular imprinted polymer (MIP) performance. The diversity and at times inappropriateness of MIP performance indicators means that the usefulness of the literature back-catalogue, for predicting, elucidating or understanding patterns in MIP efficacy, remains largely inaccessible. We hereby put forward the case that the simple binding isotherm is the most versatile and useful method of assessing and reporting MIP function, allowing direct comparison between polymers prepared and evaluated in different studies. In this study we describe how to correctly plot and interpret a bound / free isotherm and show how such plots can be readily used to predict outcomes, retro-analyze data and optimize experimental design. We propose that by adopting the use of correctly constructed isotherms as the primary form of data representation researchers will enable inter-laboratory comparisons, promote good experimental design and encourage a greater collective understanding of molecular imprinting. Copyright © 2011 John Wiley & Sons, Ltd.

We report the first development of a novel, planar, microfluidic, graphitic carbon separations column utilizing an array of graphitic micropillars of diamond cross-section as the chromatographic stationary phase. 795 nm femtosecond laser ablation was employed to subtractively machine fluidic architectures and a micropillared array in a planar, graphitic substrate as a monolithic structure. A sample injector was integrated on-chip, together with fluid-flow distribution architectures to minimize band-broadening and ensure sample equi-distribution across the micro-pillared column width. The separations chip was interfaced directly to the ESI probe of a Thermofisher Surveyor mass spectrometer, enabling the detection of test-mixture analytes following their differential retention on the micro-pillared graphitic column, thus demonstrating the exciting potential of this novel separations format. Importantly, unlike porous, graphitic microspheres, the temperature and pressure resilience of the microfluidic device potentially enables use in subcritical H(2)O chromatography.

The application of polymers as the drug delivery systems for treating oral infections is a relatively new area of research. The present study was to test the release of the antibacterial drug chlorhexidine diacetate (CHDA), the antifungal drug Nystatin (NYS) and the antiviral drug acyclovir (ACY) from polymer blends of poly(ethyl methacrylate) and poly(n-hexyl methacrylate) of different compositions. The effects of polymer blend composition, drug loading and solubilizing surfactants on the release of the drugs have been studied. Measurements of the in vitro rate of drug release showed a sustained release of drug over extended periods of time. Drug release rates decreased with increasing PEMA content in polymer blends. CHDA release rates increased steadily with increasing drug load. The drug release rates increased with the addition of surfactants. This study demonstrates that the three therapeutic agents show a sustained rate of drug release from polymer blends of PEMA and PHMA over extended periods of time. By varying polymer blend compositions as well as the drug concentration (loading), it is possible to control the drug release rates to a desired value. The drug release rate is enhanced by addition of surfactants that solubilize drugs in the polymer blends.