Comparative study of the release kinetics of osmotically active solutes from hydrophobic elastomeric matrices combined with the characterization of the depleted matrices

The release process of three osmotically active solutes with various solubilities in water (NaCl, CsNO₃, and CsCl) from silicone rubber matrices is presented. The kinetics of release for different initial loads of the salts were supplemented by measurements of the kinetics of concurrent water uptake. To gain insight on the relevant non‐Fickian transport mechanisms, the morphology, the diffusion and sorption properties and the physicochemical state of water in the salt‐depleted matrices were studied. In addition, both salt‐loaded and salt‐depleted matrices were characterized with respect to their mechanical properties. The combined information, derived from these techniques, supported the operation of a release mechanism carried out through the formation of microscopic cracks, interconnecting the permanently formed cavities inside the matrices. The results indicate that these microscopic cracks may have healed upon drying. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Release of dexamethasone from poly(N‐vinyl pyrrolidone‐co‐n‐hexyl methacrylate) copolymers of controlled hydrophilicity

A copolymer system with controlled hydrophilicity has been prepared through copolymerization technique and its capability as controlled drug release carrier is investigated. The effect of copolymer composition on water uptake, thermal properties, and morphology is reported. The water uptake increases with increasing N‐vinyl pyrrolidone content and diffusion of water molecules appears to be non‐Fickian. Dexamethasone has been selected as model drug and its controlled release from selected water stable copolymers follows for more than 1 month. Initial burst release of more than 50% occurs in 7 days. The remaining drug is released in a sustained way upto 37 days. Initial 10 h drug release pattern involves first‐order kinetics (NH73) and zero‐order kinetics (NH55), whereas initial 60% drug release mechanism appears to be non‐Fickian for NH73 (n = 0.71) and Case II transport (n = 1.24) for NH55. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013     

Controlled release of diclofenac sodium and ibuprofen through beads of sodium alginate and hydroxy ethyl cellulose blends

Controlled release of diclofenac sodium (DS) and ibuprofen (IB) drugs through sodium alginate (NaAlg)‐hydroxy ethyl cellulose (HEC) blend polymeric beads has been investigated. Beads were prepared by precipitating the viscous solution of NaAlg and HEC blend in alcohol followed by crosslinking with calcium chloride. Different formulations were developed in bead form by varying the amount of HEC, crosslinking agent, and drug concentration. Swelling studies in water, percent encapsulation of drugs, and release studies were carried out. The DS‐loaded beads have shown better release performance than the IB‐loaded beads. Diffusion parameters were evaluated from the Fickian diffusion theory. Mathematical modeling studies and drug release characteristics through bead matrices were studied by solving Fick's diffusion equation. The results are discussed in terms of drug release patterns and theoretical concentration profiles generated through matrices, considering spherical geometry of the beads. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5708–5718, 2006     

Drug diffusion in neutral and ionic hydrogels assembled from acetylated galactoglucomannan

In this study, hydrogels based on acetylated galactoglucomannan (AcGGM)—a hemicellulose present in softwood—were synthesized and examined for their properties in drug‐release systems using two model substances of different molecular weight, size, and polarity (caffeine and vitasyn blue). Neutral hydrogels were produced from functionalized AcGGM using hydroxyethyl methacrylate (HEMA) coupled via carbonyldiimidazole (CDI) and a co‐monomer in a radical‐initiated polymerization. Through a second modification reaction between the HEMA‐modified AcGGM (M‐AcGGM‐methacrylated AcGGM) and maleic anhydride, a “double‐modified” AcGGM (CM‐AcGGM‐carboxylated M‐AcGGM) was successfully formed that could be cross‐linked to form ionic hydrogels by the very same polymerization method. The neutral hydrogels showed drug release kinetics that could be easily regulated by changing the relative amount of the methacrylated AcGGM and its corresponding degree of methacrylation. The drug release rate and the Fickian swelling decreased with an increase in these two aforementioned parameters. The ionic hydrogels showed quicker release kinetics and higher swelling capabilities than the corresponding nonionic gels did, especially at neutral conditions. Under acidic conditions, the release speed was lowered as expected because of protonation of carboxylic functionalities. Based on the findings we conclude that these novel hemicellulose‐containing hydrogels have future prospects in drug release formulations, e.g., in a later stage of development for application in oral drug administration technology. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Release of norethindrone from poly(ortho esters)

The release of norethindrone from a poly(ortho ester) derived from 3,9-bis(methylene)2,4,8,10-tetraoxaspiro[5,5] undecane and 1,6-hexanediol was studied. Thin circular devices containing incorporated drug and a water soluble salt, such as sodium carbonate, sodium sulfate, or sodium chloride, were placed in water buffered at pH 7.4 at 37°C, and release of drug was followed spectrophotometrically. It was found that rate of drug release was close to zero order for long periods of time and that release of the drug from the hydrophobic matrix occurred as a consequence of osmotic imbibing of water driven by the water soluble salt. Thus, a swelling front moves at a slow and constant rate through the solid device and drug release takes place by rapid diffusion of the drug from the swelling front. Polymer erosion lags behind drug release, and no erosion takes place with basic salts such as sodium carbonate when mechanical properties of the matrix are adequate to accommodate osmotic swelling.     

Encapsulation of diclofenac sodium with acidic copolymer hydrogels based on PEG/poly(N‐isopropylacrylamide‐co‐2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid) semi‐interpenetrating network using in situ loading technique

A pH‐ and temperature‐responsive semi‐interpenetrating copolymer PEG6000/poly(NIPA‐co‐AMPS) (PEG/AMPS‐co‐NIPA SIPN), for short PEG SIPN, was made by ammonium persulfate‐initiated suspension copolymerization of N‐isopropylacrylamide, 2‐acrylamido‐2‐methylpropanesulphonic acid, and N,N′‐methylene‐bis‐acrylamide (MBAA; crosslinker) in the presence of PEG6000. The PEG SIPN copolymer matrices containing nanostructures made in the high‐temperature copolymerization resulted in channels for PEG and facile migration of drugs. In drug encapsulation or drug‐loading process, one can easily ignore or pay less attention to the interaction between a drug and its encapsulation materials; however, the ignored interactions may induce problems in drug properties or the release behavior in use. Sodium diclofenac (DFNa) precipitates as the carboxylic acid form in an acidic environment, and it is challenging to encapsulate sodium diclofenac in such an acidic matrix without precipitation of the sparingly soluble acid form of DFNa on the surface of the polymer substrate. To avoid bulky precipitation in drug loading, an in situ loading technique was developed for producing gel spheres with DFNa uniformly distributed in the polymer matrix. The technique is based on fast polymerization of spherical droplets of a pregel solution in which the drug is dissolved. Diffusion‐loading prodrugs were made in comparison with in situ loading prodrugs in thermal, release kinetics, and release behavior. Drug release profiles (in pH 7.4 phosphate buffer) show that the new drug loading technique gives controlled release during a period of about 7 days at 37°C. By contrast, gel spheres loaded with sodium diclofenac using the conventional diffusion technique produced almost total release of the drug within about 24 h. The thermal stability of sodium diclofenac, the PEG/AMPS‐co‐NIPA SIPN, and the prodrugs made with the SIPN and sodium diclofenac was studied. A near zero‐order release kinetics was found in the in vitro release of sodium diclofenac with in situ loading PEG SIPN prodrug. We have, for the first time, studied sodium diclofenac release behavior from the PEG SIPN hydrogel systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Spray drying technique to produce controlled release formulations of zidovudine—an anti‐HIV drug

This article explores the application of spray drying technique to produce microparticles of poly(D ,L ‐lactide‐co‐glycolic acid) (PLGA), as well as di‐block copolymer of polylactic acid (PLA) and polyethylene glycol (PEG) (PLA‐PEG), containing zidovudine (AZT), an anti‐HIV drug, to achieve its controlled release over an extended period of time. Of the two polymers studied, PLGA is hydrophobic, whereas PLA‐PEG is hydrophilic and the drug, AZT is water‐soluble. Formulations were developed containing 10 and 25 wt % of AZT giving encapsulation efficiencies (EE) of 66 to 86% for PLGA and 90 to 94% for PLA‐PEG di‐block copolymer. All the formulations were characterized by Fourier transform spectroscopy (FTIR) to investigate the interaction of AZT with polymers and to characterize PLA‐PEG. NMR was also employed to confirm the formation of PLA‐PEG. X‐ray diffraction was used to understand the molecular level dispersion of AZT within the polymeric matrices, while differential scanning calorimetry was employed to assess thermal properties. Scanning electron microscopy was employed to understand the surface morphology of AZT‐loaded microparticles. In vitro release experiments performed in pH 7.4 buffer media extended the release of AZT up to 125 h with PLGA, whereas 30 h were required for releasing AZT through PLA‐PEG microparticles. Cumulative release data were fitted to an empirical equation to understand the nature of release characteristics. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 000: 000–000, 2011     

Release of highly hydrophilic drugs from poly(ϵ‐caprolactone) matrices

We examine the release of two highly hydrophilic drugs, nicotine and caffeine, from poly(ε‐caprolactone) (PCL) matrices. We find that the dominant mechanism for drug release is drug diffusion through the PCL matrices. As a result, the rate of drug release (defined by the amount of drug released per unit time) decreases exponentially with time. Coating the drug‐carrying particles with a drug‐free PCL layer significantly changes the release profile: instead of exponential decay, the release rate exhibits a peak whose location (time) and magnitude vary with the diffusion coefficient of the drug in the polymer and the thickness of the coating. As a result, coating may be used to control the release rate andobtain a relatively constant rate over a period of time. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Release behavior from hydrogen‐bonded polymer gels prepared by pressurization

Our previous research showed that a simple ultra‐high‐pressure process made poly(vinyl alcohol) (PVA) solution into a macrogel and nanoparticles. To investigate the release properties of PVA hydrogels prepared by the ultra‐high‐pressure treatment, we prepared hydrogels containing model drugs by pressurizing a PVA solution with Alfa‐G Hesperidin or Oil Blue N as a water‐soluble or an oil‐soluble model drug, respectively. In the case of the oil‐soluble drug, an oil‐in‐water emulsion, Oil Blue N containing dodecane in a PVA solution, was used by homogenization before pressurization. The average diameter and the diameter distribution of oil droplets before and after the ultra‐high‐pressure treatment were almost the same. However, the PVA hydrogel prepared at 10,000 atm for 10 min exhibited the slowest release rate of model drugs. Thus, we found that the release rates of the model drugs from the PVA hydrogels were controlled by the degree of crosslinking in the resulting gels, which was determined from the operation parameters of the ultra‐high‐pressure treatment, such as the pressure, time, and concentration of the PVA solution. Therefore, an ultra‐high‐pressure process is promising for drug‐carrier development because of the nonharmful simple preparation process. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

A Comparison of Electric‐Field‐Driven and Pressure‐Driven Fiber Generation Methods for Drug Delivery

Polymeric fibers are prepared by using electric field driven fiber production technology—electrospinning and pressure driven fiber production technology—pressurized gyration. Fibers of four different polymers: polyvinylidene fluoride (PVDF), poly(methyl methacrylate (PMMA), poly(N‐isopropylacrylamide), and polyvinylpyridine (PVP), are spun by both techniques and differences are analyzed for their suitability as drug carriers. The diameters of electrospun fibers are larger in some cases (PVDF and PMMA), producing fibers with lower surface area. Pressurized gyration allows for a higher rate of fiber production. Additionally, drug‐loaded PVP fibers are prepared by using two poorly water‐soluble drugs (Amphotericin B and Itraconazole). In vitro dissolution studies show differences in release rate between the two types of fibers. Drug‐loaded gyrospun fibers release the drugs faster within 15 min compared to the drug‐loaded electrospun fibers. The findings suggest pressurized gyration is a promising and scalable approach to rapid fiber production for drug delivery when compared to electrospinning.     

Formation of silk fibroin hydrogel and evaluation of its drug release profile

Silk hydrogels are interesting materials to be used as matrix in controlled drug delivery devices. However, methods to accelerate fibroin gelation and allow the drug incorporation during the hydrogel preparation are needed in literature. In this article we report the preparation of silk fibroin hydrogels with addition of several contents of ethanol, used to accelerate fibroin gelation kinetics, and we also evaluate the potential of these hydrogels to be used as matrices for drug delivery. Chemical and conformational properties did not change despite the amount of ethanol incorporated in the hydrogel. Hydrogels containing diclofenac sodium dissolved in ethanol showed a faster initial release of the drug than hydrogels with the drug dissolved in water but equilibrium was reached later. This indicates a more sustained drug delivery from hydrogels in which the model drug was dissolved in ethanol. Fibroin hydrogels confirm their promising use as biopolymeric matrices for controlled drug release. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41802.     

Novel methyl cellulose‐grafted‐acrylamide/gelatin microspheres for controlled release of nifedipine

Naturally available carbohydrate polymers such as methylcellulose (MC) and gelatin (Ge) have been widely studied in the previous literature for controlled release (CR) applications. In this study, methyl cellulose‐g‐acrylamide/gelatin (MC‐g‐AAm/Ge) microspheres were prepared by water‐in‐oil (W/O) emulsion method and crosslinked with glutaraldehyde to encapsulate with nifedipine (NFD), an antihypertensive drug. The microspheres prepared were characterized by differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and laser particle size analyzer. DSC thermograms of NFD‐loaded AAm‐MC/Gel microspheres confirmed the molecular level distribution of NFD in the matrix. SEM indicated the formation of spherical particles. Swelling experiments supported the drug diffusion characteristics and release data of the matrices. Cumulative release data were analyzed using an empirical equation to understand the nature of transport of drug through the matrices. Controlled release characteristics of the matrices for NFD were investigated in pH 7.4 media. Drug was released in a controlled manner up to 12 h. Particle size and size distribution of the microspheres as studied by laser light diffraction particle size analyzer indicated their sizes to be around 120 μm. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis of hydrogel for drug delivery studies utilizing photoinitiator‐free photopolymerization based on the donor/acceptor pair,N‐vinylpyrrolidinone and hydroxypentyl maleimide

Photo‐differential scanning calorimetry (photo‐DSC) was used to study the rate of photoinitiator‐free copolymerization of a donor/acceptor pair involving N‐vinylpyrrolidinone (NVP), and a water‐soluble N‐substituted maleimide, hydroxypentyl maleimide (HPMI). Glucose, 1,1‐diethoxy ethane (DEE) and isopropyl alcohol (IPA) were included for the evaluation of their efficiencies as hydrogen donors, and glucose was shown to be the most efficient in enhancing the rate of polymerization. This photoinitiator (PI)‐free system was extended to hydrogel preparation using the radiation method with UV as the radiation source based on the same donor/acceptor pair, ie NVP/HPMI, in the presence of glucose as the hydrogen donor. Swelling and drug release tests showed that this hydrogel exhibited high swelling ability and a rather fast drug release rate when using theophylline as the model drug. These tests also revealed that the drug release kinetics and the water diffusion into this hydrogel did not adhere to the Fickian model. Cytotoxicity testing showed no evidence of this hydrogel being cytotoxic. © 2002 Society of Chemical Industry     

Preparation,characterization and in vitro drug release properties of polytrimethylene carbonate/polyadipic anhydride blend microspheres

Polyadipic anhydride (PAA), an aliphatic polyanhydride, and polytrimethylene carbonate (PTMC), an aliphatic polycarbonate, were synthesized via ring opening polymerization of oxepan‐2,7‐dione and melt‐condensation of trimethylene carbonate (1,3 dioxan‐2‐one), respectively. PTMC–PAA blend microspheres containing different ratios of buprenorphine HCl (2, 5, and 10%) were prepared by an oil‐in‐oil emulsion solvent removal method. Microspheres with different ratios of PTMC–PAA (85/15, 70/30, and 55/45) containing 5% buprenorphine HCl were prepared. Microspheres were spherical with visible cracks and pores on the surface. The average particle size of microspheres was around 200 μm for all microspheres. Drug loading efficiency of PTMC–PAA microspheres (85/15, 70/30, and 55/45) was 97.2, 95.2, and 70.2%, respectively. With the increase in the PTMC ratio, the melting point and the enthalpy of melting were both decreased. The mechanism for drug release from PTMC–PAA blend microspheres were generally a combination of drug diffusion through polymers and biodegradation of the polymers. In first three days, the release from microspheres followed zero order kinetics and was dependent on the PAA content. After three days the drug release from microspheres followed first order kinetics. In conclusion it was demonstrated that buprenorphine HCl release from microspheres could be successfully controlled by using different ratios of PTMC–PAA blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2377–2383, 2006     

Poly(ethyl glycol) assisting water sorption enhancement of poly(ε‐caprolactone) blend for drug delivery

Poly(ε‐caprolactone) (PCL) has been thermally synthesized, and then fractionated to blend with poly(ethyl glycol) (PEG). Blend films of PCL and PEG have been prepared by solution casting. Fourier transform infrared spectrum and differential scanning calorimetry of the films have been carried out, and the results indicate some hydrogen bonding interaction between the two components, which is resulted from the carbonyl groups of PCL and the hydroxyl end‐groups of the low‐molecular‐weight PEG. Scanning electron microscope images of the blend films reveal porous network structures for their surfaces and for their inner parts and the porous structure becomes more pronounced with the increase of PEG in the blend film. Ibuprofen (IBU) was used as the model drug to test the drug release behavior for the PCL/PEG blend matrices. The results show that IBU could be released from the blend tablets rapidly, and the release rate increases with PEG content. Analysis of the release profiles indicates PCL erosion control release mechanism of pure PCL tablet, but drug diffusion control of the blend tablet, because PEG can absorb water to allow water feasible to diffuse into drug core and dissolve drug. Therefore, the interconnected channels in the blend matrices and the hydrophilic nature of PEG contribute to the improvement of the IBU release rate. The research indicates that drug release rate from PCL based material could be efficiently improved by addition of small amount of hydrophilic low‐molecular‐weight PEG. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation of a biodegradable poly(vinyl alcohol)–starch composite film and its application in pesticide controlled release

With the herbicide 2,4‐dichlorophenoxyacetic acid (2,4‐D) as a model drug, a series of poly(vinyl alcohol)–starch (PVA–ST) composite films for controlled drug release were prepared by a casting method. The morphology, structure, and release properties were systematically investigated. The results show that when the PVA–ST composite film containing 2,4‐D (PSD) was immersed in water, the drug‐release rate was high, whereas the introduction of sodium montmorillonite (Na‐MMT) and an alginate ion‐crosslinking structure to PSD significantly reduced the release rate and maintained the sustained release of the model drug for a longer period. A leaching experiment through the soil layer showed that the PSD drug‐loaded film with Na‐MMT and the alginate ion‐crosslinking structure (PSDMA) possessed good release properties. The cumulative leached amount of the herbicide 2,4‐D after eight irrigations was reduced to 57.6% from 100%. In addition, the PSDMA film showed favorable mechanical and thermal properties. This composite film is expected to have potential applications in the fields of agriculture, drug delivery, and more. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45051.     

Development of Bigels Based on Stearic Acid–Rice Bran Oil Oleogels and Tamarind Gum Hydrogels for Controlled Delivery Applications

In the last few decades, different types of gels have been widely studied as potential drug delivery carriers. In this paper, we propose the synthesis of an oleogel, a tamarind gum hydrogel, and bigels for applications as drug delivery matrices. The oleogel was prepared by mixing stearic acid and rice bran oil, whereas the hydrogel was prepared by mixing tamarind gum with a hydroethanolic solution. Hydrogel‐in‐oleogel and oleogel‐in‐hydrogel bigels were prepared by mixing the hydrogel and the oleogel. The suitability of the formulations for controlled drug release applications was thoroughly examined using microscopy, Fourier transform infrared (FTIR) spectroscopy, as well as mechanical, electrical, thermal, drug release, and antimicrobial studies. An alteration in the microarchitecture of the bigels is observed when the oleogel and the hydrogel are mixed in varying proportions. The associative interactions within the formulations increase with the increase in the hydrogel content. The bigels exhibit the presence of stearic acid melting endotherm (associated with the oleogel) and water evaporation endotherm (associated with the hydrogel). This study suggests that the hydrogel has lowest bulk resistance compared to the other formulations. The structural breakdown of the bigels is composition‐dependent, and the bulk electrical resistance is mainly governed by the oleogel phase. An increase in the diffusion of the moxifloxacin HCl from the formulations is observed with the increase of the hydrogel proportion, which in turn increases the rate of release of the drug. The proposed formulations also exhibit good antimicrobial efficacy. The analysis of these properties suggests that specific formulations can be tailored by need‐based applications of the drug release rate.     

THE EFFECT OF DRUG DISSOLUTION ON DRUG RELEASE FROM SWELLING POLYMERIC MATRICES: MATHEMATICAL MODELING

A mathematical model of simultaneous dissolution and diffusion controlled drug release from swellable, non-erodible viscoelastic polymer matrices is developed. The model assumes that the drug is loaded into the dry matrix as a solid phase. Two unsteady-state mass balances are required for both the drug and the incoming external penetrant. The Camera-Roda and Sarti equation is considered for the determination of the penetrant uptake, while Ficlc's equation accounting for the density gradient developing in the matrix is considered for the drug diffusion. Assuming that upon dissolution a drug phase transition may occur which affects the drug solubility without altering the diffusion coefficient. This analysis revealed that the features of the drug release kinetics are sensibly affected by the viscoelastic properties of the swollen matrices and by the drug dissolution and phase transition rates.     

Effect of silica and poly(ethylene glycol) on the in vitro release rate of 2‐pyridine aldoxime chloride from polysiloxane matrices

The release rate of 2‐pyridine aldoxime chloride (PAM‐Cl) from polysiloxane matrices was found to be in the order poly(vinylmethyldiethylsiloxane) (P(VM‐DE)S) > poly(dimethyldiethyl siloxane) P(DM‐DE)S > poly(vinylmethylsiloxane) (PVMS) > poly(dimethylvinylmethylsiloxane) (P(DM‐VM)S) > poly(dimethylsiloxane) (PDMS). The time for 80% PAM‐Cl release from polysiloxane matrices was found to be in the range 5–14 h. Incorporation of silica (5–10%) as a filler in these matrices reduced the release of PAM‐Cl and in some cases stopped drug release completely. However, the incorporation of crosslinked poly(ethylene glycol) (PEG) (5–20%) in polysiloxane matrices increased the release rate and reduced the time for 80% drug release. Slow release formulations were made by incorporating 5% silica and 5–20% PEG in PDMS, keeping the PAM‐Cl and PEG ratio 1:1. The formulations PDMS + 5% silica + 5–20% PEG + 5–20% PAM‐Cl gave a slow release of PAM‐Cl and the time for 80% drug release was found to be 12 h in each case at pH 7.4 and 37 °C. PVMS and siloxane copolymers showed times for 80% drug release of 6–10 h in comparison with 12 h for PDMS. Diffusion coefficient values for PAM‐Cl–PDMS system are also calculated. © 2000 Society of Chemical Industry     

Design of hemocompatible poly(DMAEMA‐co‐PEGMA) hydrogels for controlled release of insulin

This works aims at (i) studying the antiadhesive properties and the hemocompatibility of poly[2‐(dimethylamino)ethyl methacrylate]‐co‐poly[(ethylene glycol)methacrylate] [poly(DMAEMA‐co‐PEGMA)] copolymers and (ii) investigating the insulin delivery kinetics through hydrogels at physiological pH. A series of poly(DMAEMA‐co‐PEGMA) hydrogels have been synthesized, and their controlled composition was confirmed by X‐ray photoelectron spectroscopy. Then, antibiofouling properties of hydrogels—fibrinogen, erythrocytes, and thrombocytes adhesion—are correlated to their molecular compositions through their hydrophilic properties. As DMAEMA/PEGMA ratio of 70/30 (D70) offers the best compromise between pH sensitivity and hemocompatibility, it is selected for investigating the kinetic rate of insulin release at physiological pH, and the diffusion coefficient of insulin in gel is found to be 0.64 × 10^?7 cm² s^?1. Overall, this study unveils that poly(DMAEMA‐co‐PEGMA) copolymers are promising hemocompatible materials for drug delivery systems. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42365.