Hydrogel Films Research Articles

Waste to Wealth: Near-Infrared/pH Dual-Responsive Copper-Humic Acid Hydrogel Films for Bacteria-Infected Cutaneous Wound Healing.

The clinical applications of currently used photosensitizers are limited by high costs, inconvenient preparation, suboptimal biodegradability, and a lack of biological activity. Humic acids (HAs) show photothermal activity and can be used as a photosensitizer for photothermal therapy. In the presence of various functional groups, HAs are endowed with anti-inflammatory and antioxidant activities. The solubility of HAs is dependent on the pH value, which is soluble in neutral to alkaline conditions and undergoes a conformational change to a coiled and compact structure in acidic conditions. Additionally, Cu2+ is an emerging therapeutic agent for cutaneous wounds and can be chelated by HAs to form complexes. In this study, we explore the ability of HAs to modulate the inflammatory response, particularly macrophage polarization, and the potential underlying mechanism. We fabricate a near-infrared (NIR)/pH dual-responsive Cu-HAs nanoparticle (NP)-based poly(vinyl alcohol) (PVA) hydrogel film loaded with SEW2871 (SEW), a macrophage recruitment agent, to treat bacteria-infected cutaneous wounds. The results show that HAs could promote M2 macrophage polarization in a dose-dependent manner. The Cu-HAs NPs successfully eradicated bacterial infection through NIR-induced local hyperthermia. This PVA@Cu-HAs NPs@SEW hydrogel film improves tissue regeneration by promoting M2 macrophage polarization, alleviating oxidative stress, enhancing angiogenesis, and facilitating collagen deposition. These findings highlight the therapeutic potential of PVA@Cu-HAs NPs@SEW hydrogel film for the treatment of bacterially infected cutaneous wound healing.

A smartphone-based inverse opal hydrogel film aptasensor for mycotoxin detection by the naked eye

Ochratoxin A (OTA), a carcinogenic mycotoxins, poses a significant threat to human health. The current detection methods exhibit advantages such as high sensitivity and good selectivity. However, The methods applicability for on-site detection remains hindered by complex operational procedures and the requirement for bulky testing instruments. Here, to address this limitation, we present a novel portable platform for naked-eye detection of OTA using photonic crystal (PC) inverse opal hydrogel films based on the smartphone. The inverse opal hydrogel film was fabricated by integrating hydrogel within PC templates, while a binding aptamer was employed to selectively recognize OTA. In the absence of OTA, the film displayed a vibrant red. With increasing OTA concentration, the diffraction peak progressively shifted toward the blue region of the spectrum. Leveraging a portable microscope, and captured the color change using a smartphone and developed a self-written algorithm to extract the H value of the image, enabling quantitative detection of OTA concentration. This portable platform has demonstrated exceptional reliability and convenience, boasting a remarkable detection limit of 1 μg/mL. Furthermore, its versatility extends to the detection of other mycotoxins, making it a promising tool for broader mycotoxin detection applications.

Preparation of isocyanate-containing hydrogel films as antibacterial enzyme immobilization matrices

Sulfobetaine-based isocyanate-containing hydrogel films were synthesized on glass surfaces and the immobilization of small molecules and proteins onto those films was demonstrated. Synthesis of hydrogel films and their functionalizations were confirmed using FTIR spectroscopy. Obtained polymer films were used as matrices for the immobilization of the antibacterial enzyme lysostaphin (Lys). Successful immobilization of Lys enzyme was demonstrated using FTIR and Bradford analyses. The antibacterial activity of enzyme-immobilized surfaces against different Staphylococcus aureus (S. aureus) bacterial strains was evaluated. Enzyme-conjugated surfaces showed 90% killing efficacy against S. aureus 35 bacteria, and the antibacterial activity of those surfaces was maintained for at least 30 days and multiple exposures to the bacteria. The enzyme-immobilized hydrogel coatings reported here provide a promising antibacterial surface against S. aureus.

Preparation of elastic hydrogel films via in-situ ketalization of Poly(vinyl alcohol) and ZnO nanoparticle doped Poly(vinyl ketal) films as antibacterial surface

Cross-linked and flexible poly(vinyl acetone ketal) (PV-A-K) films have been prepared as a result of ketalization reaction and monolith formation of poly(vinyl alcohol) (PVA), which has the feature of forming films quickly and is frequently used in biological fields. In this novel method, flexible PV-A-K films have been produced simply and in a short time accompanied by monolith formation without any catalyst in acetone. The effect of acetone ratio on the physical properties (i.e., swelling and mechanical properties) of such formations has been investigated to reveal significant influences of it. In addition, zinc oxide (ZnO) nanoparticles synthesized via the solvothermal method have been doped into PV-A-K films during film preparation. The prepared PV-A-K and ZnO doped PV-A-K films have been characterized with SEM, XRD, and FT-IR. Their mechanical properties have been investigated with a universal mechanical test machine. The acetone ratio is quite effective both on the porosity and stress/strain properties of the films. Antibacterial activities of the films are evaluated against four different strains (E. coli, S. aureus, P. aeruginosa, and E. faecalis) via the disk diffusion method. The films are selectively effective against S. aureus. These highly flexible and elastic films have great potential for biomedical applications, wound dressing, and antibacterial surface preparation.

Photocatalytic hydrogel film assisted forward osmosis (PFO) for water treatment: Sustainable performance and contaminant control

The integration of catalytic oxidation with forward osmosis (FO) holds promising potential to address two crucial challenges encountered by FO: fouling and unsustainable performance, but suitable approaches are still rare. Herein, we have successfully developed a photocatalysis-assisted forward osmosis (PFO) system. In the PFO, a self-made porous carbon nitride doped functional carbon nanotube photocatalytic hydrogel film (PCN@CNTM) was engaged in the FO process in an inventive way by simply sticking to the commercial FO membrane surface, preventing damage to the membrane from the catalyst's direct insertion and delaying the assault from the oxidation groups. PFO allowed organic pollutants to decompose in the feed solution (90%) and on the membrane surface, regulating the water chemical potential and giving the FO membrane antifouling properties. This resulted in sustainable water flux (11.8 LMH) with no significant membrane fouling in PFO, whereas in FO alone there was a significant fouling and flux drop (from 12.73 to 7.23 LMH in 4 h). Moreover, the expensive FO membrane was protected while the hydrogel film can be replaced on demand. The PFO exemplifies the concept of synergistic technology integration, presenting a new perspective on harnessing the strengths of distinct technologies in a mutually beneficial manner.

Stretchable porous conductive hydrogel films prepared by emulsion template method as flexible sensors

Conductive hydrogels with stretchability, breathability and long-term stability have attracted increasing attention for the applications in interactive wearable devices, artificial prosthetics, and intelligent robots. In this paper, a stretchable (up to 254 %), well breathable (vapor transmission up to 1.231×10−2 g·cm−2·h−1), and stable conductive (1.21 S/m) hydrogel films (Gel/PPy/Ag) was prepared by gel-template immersion method using gelatin as gel networks, polypyrrole (PPy) and silver (Ag) as conductive reinforcing filler and Span 80 as emulsion template. The film could maintain flexibility and conductivity after stored in an environment of –20 °C or 25 °C for 20 days. The excellent frost resistance and water retention ensured the practical application of the porous organic hydrogel film with environmental adaptability and long-term stability. The strain sensor made from the Gel/PPy/Ag films presented excellent sensitivity (GF reached 2.034), good durability, fast response (0.34 s) and recovery ability (0.36 s). It monitored weak and vigorous human motions effectively and sensitively. The Gel/PPy/Ag flexible electrodes realized the real-time sensitive detection of human Electrocardiogram (ECG) and electromyogram (EMG) signals and precision sensing control of the manipulator arm. The Gel/PPy/Ag hydrogel and the prepared flexible electronic devices have broad application prospects in the field of health monitoring, motion monitoring, operation control and other soft electronic devices.

Bovine Serum Albumin Molecularly Imprinted Electrochemical Sensors Modified by Carboxylated Multi-Walled Carbon Nanotubes/CaAlg Hydrogels.

In this paper, sodium alginate (NaAlg) was used as functional monomers, bovine serum albumin (BSA) was used as template molecules, and calcium chloride (CaCl2) aqueous solution was used as a cross-linking agent to prepare BSA molecularly imprinted carboxylated multi-wall carbon nanotubes (CMWCNT)/CaAlg hydrogel films (MIPs) and non-imprinted hydrogel films (NIPs). The adsorption capacity of the MIP film for BSA was 27.23 mg/g and the imprinting efficiency was 2.73. The MIP and NIP hydrogel film were loaded on the surface of the printed electrode, and electrochemical performance tests were carried out by electrochemical impedance spectroscopy (EIS) and differential pulse voltammetry (DPV) using the electrochemical workstation. The loaded MIP film and NIP film effectively improved the electrochemical signal of the bare carbon electrode. When the pH value of the Tris HCl elution solution was 7.4, the elution time was 15 min and the adsorption time was 15 min, and the peak currents of MIP-modified electrodes and NIP-modified electrodes reached their maximum values. There was a specific interaction between MIP-modified electrodes and BSA, exhibiting specific recognition for BSA. In addition, the MIP-modified electrodes had good anti-interference, reusability, stability, and reproducibility. The detection limit (LOD) was 5.6 × 10-6 mg mL-1.

Dual-Emitting Mixed-Lanthanide Metal-Organic Framework for Ratiometric and Quantitative Visual Detection of 2,6-Pyridine Dicarboxylic Acid.

The detection of the major biomarker of Bacillus anthracis, 2,6-dipicolinic acid (DPA), has attracted great interest in recent years. In this work, mixed-lanthanide metal-organic frameworks (M'LnMOFs), TbxEu1-x-cppa (cppa = 5-(5-carboxypyridin-3-yl)isophthalic acid), with different Tb/Eu ratios, were solvothermally synthesized. The results reveal that ratiometric fluorescent probe [Tb0.533Eu0.467-(Hcppa)1.5(H2O)(DMF)]·3H2O is water and acid-base stable and exhibits excellent sensitivity (LOD = 2.286 μM), high selectivity, and fast response (<2 min) for the detection of DPA. Due to the blocked energy transfer from Tb3+ to Eu3+ and the inner filter effect upon the addition of DPA, the fluorescent probe shows a distinct color change from orange-red to green. Furthermore, the visual detection of DPA was realized by identifying the RGB values of MOF-based agarose hydrogel films via a smartphone, highlighting the practical application of the fluorescent probe for DPA detection under aqueous solution conditions.

Super-Stretchable Hydrogel Films with High Fracture Energy Enabled by Coordination Nanoparticles as Multifunctional Wound Dressings

Super-Stretchable Hydrogel Films with High Fracture Energy Enabled by Coordination Nanoparticles as Multifunctional Wound Dressings

Ultrasensitive QCM sensor development for monitoring of methyl orange dye in aqueous phase based on novel cross-linked chitosan/PVA/GO/Ce-ZnO nanocomposite film

In this study, chitosan/polyvinyl alcohol (CS/PVA) nanocomposite hydrogels were produced using the solution casting method due to their non-toxic and biocompatible nature. The best composition was chosen and cross-linked with glutaraldehyde, after which a certain amount of graphene oxide nanosheets (GO NS) and cerium doped zinc oxide nanoparticles (Ce-ZnO NPs) were added to develop nanocomposite hydrogel films (NCs). X-ray diffractometer (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FTIR), N2 adsorption–desorption isotherm, Raman spectroscopy, and thermogravimetric analyzer (TGA/DTG) were used to characterize the films. The synthesized composites were also evaluated for sensitivity towards methyl orange (MO) dye based on the quartz crystal microbalance (QCM) technique at different pH of MO solution. XRD results revealed that all films whether CS film or the blend CS/PVA/GO and CS/PVA/GO/Ce-ZnO films exhibited good crystallinity. The SEM images depicted the surface morphology of films, which clarified the adding effect of GO NS and Ce-ZnO NPs on the surface morphology of CS/PVA films. While the EDS analysis demonstrated the elemental composition of CS/PVA/GO/Ce-ZnO film. In the same context, the TEM images emphasized the results obtained by the SEM examination and showed no phase separation of the polymers. Whereas AFM showed an increase in surface roughness with adding of GO NS, while was decreased in the case of Ce-ZnO NPs addition. Surface area and pore size distribution results revealed significant differences due to the addition of GO NS and Ce-ZnO NPs to the CS/PVA matrix. The chemical structure of all films was investigated using the Raman shift and their thermal behaviours were also analysed. Finally, the results of QCM sensor-based prepared films showed that the inclusion of GO NS and Ce-ZnO NPs boosted the monitoring performance of sensor films towards MO dye. Furthermore, the sensors-based nanocomposite films presented the same monitoring attitude for MO at different pH.

A novel nitrogen-doped carbon dots as “on-off-on” fluorescent sensor for ultrasensitive and visual quantitative detection of mercuric (II) and glutathione

A novel nitrogen-doped carbon dots (NCDs) was prepared composed of anhydrous citric acid and 2-amino-1-H-benzimidazole with solid state method. The XPS and FT-IR spectra indicate that lot of chelating groups such as -OH, -COOH and -NH2 are attached on the surface of NCDs. NCDs exhibited the characteristic fluorescence property and its fluorescence spectra gradually red-shifted with the increase of excitation wavelengths. The prepared NCDs in water solution has highly selective “turn-off” fluorescence response towards Hg2+ over the other metal ions and common anions with a low detection limit of 3.50 μM. Furthermore, NCDs presented the successive identification and detection capability, NCDs@Hg2+ displayed highly selective “turn-on” fluorescence response towards the bioactive glutathione (GSH) over the other amino acids with a low detection limit of 3.43 μM. The “turn-off” fluorescence of NCDs was caused by the selective coordination with Hg2+ through both static and dynamic quenching mechanisms, and the fluorescence recovery can be attributed to the removal of Hg2+ from the complex NCDs@Hg2+ by GSH. The hydrogel films containing NCDs and NCDs@Hg2+ can semi-quantitatively detect Hg2+ and GSH in micromolar level with naked eyes under UV lamp, respectively. In addition, the prepared NCDs have satisfactory recovery in detection of Hg2+ and GSH in practical water samples and human serum samples. This work proves the N-doped carbon NCDs are efficient material as fluorescence chemosensors to identify and detect metal ions and bioactive substances in practical samples.

Macrofibers with tunable mechanical performance and reversible rotational motion based on a bacterial cellulose hydrogel film

Mechanically twisting a yarn is a useful and important method for creating internal stress, changing macromolecular orientation, and affording interesting fiber properties, including mechanical, structural, physical and chemical properties. Bacterial cellulose (BC) nanofibers are a new type of highly crystalline bionanofibers exhibiting excellent intrinsic mechanical properties. Herein, BC macrofibers with a diameter of 0.35–0.53 mm were prepared from BC hydrogel films using a two-step technique involving drying and twisting processes. Moreover, the effects of the drying method (oven- and freeze-drying) and those of the processing steps on the morphologies, structures, and physicochemical properties of the macrofibers were investigated. Results indicated that only the wet twisting–first process affords continuous macrofibers with a compact and uniform structure. The tensile strength and elongation at break of the macrofibers were 199 MPa and 24%, respectively. Furthermore, by introducing graphene oxide (GO) to the macrofibers, a photothermal and moisture actuator was facilely constructed, which could produce a twisting motion of 0.39 rpm and an untwisting motion of 0.6 rpm. This study provides insights into methods to easily alter the properties of BC macrofibers, which is pivotal for the macrofiber’s potential application in intelligent devices.

Construction of a logic gate sensitive monitoring system of Graphdiyne/Poly(N,N-dimethylacrylamide) binary structure films for environmental pollutant phenylhydrazine

In this work, binary hydrogel films based on Graphdiyne/Poly(N,N-dimethylacrylamide (GDY/PDEA) were successfully polymerized and assembled on pyrolytic graphite (PG) electrode surface. When phenylhydrazine (PHz) as an active electrochemical probe in solution exhibits reversible cyclic voltammetric (CV) behaviors in response to temperature, salt and pH at the membrane electrode. The CV signals of PHz were significantly enhanced by electrocatalysis of GDY layer of the films. And the mechanism of membrane reaction was discussed and studied. The presence of protonated PHz determines the pH-sensitive property of the system. During pH adjustment with esterase urease, in situ enzymatic electrocatalysis that may be accelerates the electron transfer rate at the electrode surface. The structural alterations of PDEA hydrogels under multiple conditions were attribute to the temperature response and salt concentration–response. GDY films can also have an effect on the CV response signals. In conclusion, a multi-stimulus response hydrogel film environmental sensor has been constructed, and a 5-input/5-output logic gate system including OR, AND and NOT has been successfully constructed. And constructed 2-to-4 decoder and 2-to-1 encoder two logic devices. It provides a new method to increase the complexity of the environmental pollutant monitoring calculation system.

Preparation and Characterization of Hydrogel Films and Nanoparticles Based on Low-Esterified Pectin for Anticancer Applications.

Prospective adjuvant anticancer therapy development includes the establishing of drug delivery systems based on biocompatible and biodegradable carriers. We have designed films and nanoparticles (NPs) based on low-esterified pectin hydrogel using the ionic gelation method. We investigated morphology, nanomechanical properties, biocompatibility and anticancer activity. Hydrogel films are characterized by tunable viscoelastic properties and surface nanoarchitectonics through pectin concentration and esterification degree (DE), expressed in variable pore frequency and diameter. An in vitro study showed a significant reduction in metabolic activity and the proliferation of the U87MG human glioblastoma cell line, probably affected via the adhesion mechanism. Glioma cells formed neurosphere-like conglomerates with a small number of neurites when cultured on fully de-esterified pectin films and they did not produce neurites on the films prepared on 50% esterified pectin. Pectin NPs were examined in terms of size distribution and nanomechanical properties. The NPs' shapes were proved spherical with a mean diameter varying in the range of 90-115 nm, and a negative zeta potential from -8.30 to -7.86 mV, which indicated their stability. The NPs did not demonstrate toxic effect on cells or metabolism inhibition, indicating good biocompatibility. Nanostructured biomaterials prepared on low-esterified pectins could be of interest for biomedical applications in adjuvant anticancer therapy and for designing drug delivery systems.

Combination of synthetic and natural polymers on the characteristics and evaluation of transdermal hydrogel-forming microneedles preparations integrated with direct compressed tablets reservoir sildenafil citrate

Erectile dysfunction (ED) is a disorder of the male reproductive organs due to the inability to achieve penile erection. Hydrogel-forming microneedles (HFMs) integrated with direct compression tablets (DCT) reservoir SC was developed. HFMs were produced utilizing polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), and chitosan as a combination of a mixture of synthetic and natural polymers as well as glutaraldehyde as a crosslinking agent. The swelling study of hydrogel film for all formulas had a swelling percentage profile >900%. Characterization for all HFMs formulas possessed a good profile with a percentage reduction in height of MNs <10% and was considered capable of penetrating the dermis layer. Ex vivo permeation studies on HFMs with DCT reservoir SC showed that the largest amount of SC drug permeated at 24 h was 3384.7 ± 90.81 μg/cm2. This study has succeeded in presenting the development of a transdermal preparation of HFMs integrated with DCT reservoir SC.

An elaborate biomolecular keypad lock based on electrochromism of viologen derivatives and bioelectrocatalytic reduction of CO2 at supramolecular hydrogel film electrodes

Herein, the short peptide N-fluorenemethoxycarbonyl diphenylalanine (Fmoc-FF) was used to immobilize both diallyl viologen (DAV) and the enzyme formate dehydrogenase (FDH) to form Fmoc-FF/DAV/FDH supramolecular hydrogel films on an electrode surface by a simple solvent-controlled self-assembly method. The DAV component in the films exhibited multiple properties, such as electrochromism and electrofluorochromism, and acted as an electrochemical mediator. A high efficiency of bioelectrocatalytic reduction of CO2 to formate (HCOO−) was obtained by the natural FDH enzyme and the artificial coenzyme factor DAV both immobilized in the same films. The supramolecular hydrogel films with CO2, voltage and light as stimulating factors and current, fluorescence and UV–vis extinction as responsive signals, were further applied for the construction of complex biomolecular logic systems and information encryption. A 3-input/7-output biomolecular logic gate and several logic devices, including an encoder/decoder, a parity checker, and a keypad lock, were constructed. Especially, the biomolecular keypad lock with 3 types of signals as outputs significantly enhanced the security level of information encryption. In this work, a supramolecular self-assembly interface was simply fabricated with complex biomolecular computational functions using immobilized molecules as the computational core, greatly broadening the application range of supramolecular hydrogel films and providing an idea for new designs of bioinformation encryption through the use of a simple film system.

Synthesis and Evaluation of Functionalized Polyurethanes for pH-Responsive Delivery of Compounds in Chronic Wounds.

Chronic wounds, depending on the bacteria that caused the infection, can be associated with an extreme acidic or basic pH. Therefore, the application of pH-responsive hydrogels has been instigated for the delivery of therapeutics to chronic wounds. Herein, with the aim of developing a flexible pH-responsive hydrogel, we functionalized hydrophilic polyurethanes with either cationic (polyethylene imine) or anionic (succinic anhydride) moieties. A comprehensive physicochemical characterization of corresponding polymers was carried out. Particularly, when tested in aqueous buffers, the surface charge of hydrogel films was closely correlated with the pH of the buffers. The loading of the cationic and anionic hydrogel films with various compound models (bromophenol blue; negatively charged or Pyronin Y; positively charged) showed that the electrostatic forces between the polymeric backbone and the compound model will determine the ultimate release rate at any given pH. The potential application of these films for chronic wound drug delivery was assessed by loading them with an antibiotic (ciprofloxacin). In vitro bacterial culturing was performed using Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Results showed that at the same drug dosage, different release profiles achievable from cationic and anionic polyurethanes can yield different degrees of an antibacterial effect. Overall, our results suggest the potential application of cationic and anionic hydrophilic polyurethanes as flexible pH-responsive materials for the delivery of therapeutics to chronic wounds.

Nanocomposite Hydrogel Films Based on Sequential Interpenetrating Polymeric Networks as Drug Delivery Platforms.

In this study, novel materials have been obtained via a dual covalent and ionic crosslinking strategies, leading to the formation of a fully interpenetrated polymeric network with remarkable mechanical performances as drug delivery platforms for dermal patches. The polymeric network was obtained by the free-radical photopolymerization of N-vinylpyrrolidone using tri(ethylene glycol) divinyl ether as crosslinker in the presence of sodium alginate (1%, weight%). The ionic crosslinking was achieved by the addition of Zn2+, ions which were coordinated by the alginate chains. Bentonite nanoclay was incorporated in hydrogel formulations to capitalize on its mechanical reinforcement and adsorptive capacity. TiO2 and ZnO nanoparticles were also included in two of the samples to evaluate their influence on the morphology, mechanical properties and/or the antimicrobial activity of the hydrogels. The double-crosslinked nanocomposite hydrogels presented a good tensile resistance (1.5 MPa at 70% strain) and compression resistance (12.5 MPa at a strain of 70%). Nafcillin was loaded into nanocomposite hydrogel films with a loading efficiency of up to 30%. The drug release characteristics were evaluated, and the profile was fitted by mathematical models that describe the physical processes taking place during the drug transfer from the polymer to a PBS (phosphate-buffered saline) solution. Depending on the design of the polymeric network and the nanofillers included, it was demonstrated that the nafcillin loaded into the nanocomposite hydrogel films ensured a high to moderate activity against S. aureus and S. pyogenes and no activity against E. coli. Furthermore, it was demonstrated that the presence of zinc ions in these polymeric matrices can be correlated with the inactivation of E. coli.

Crosslinking Chitosan with Silver-Sulfur Doped Graphene Quantum Dots: An Efficient Antibacterial Nanocomposite Hydrogel Films

Crosslinking Chitosan with Silver-Sulfur Doped Graphene Quantum Dots: An Efficient Antibacterial Nanocomposite Hydrogel Films

A Platform for Assessing Cellular Contractile Function Based on Magnetic Manipulation of Magnetoresponsive Hydrogel Films.

Despite significant advancements in in vitro cardiac modeling approaches, researchers still lack the capacity to obtain in vitro measurements of a key indicator of cardiac function: contractility, or stroke volume under specific loading conditions-defined as the pressures to which the heart is subjected prior to and during contraction. This work puts forward a platform that creates this capability, by providing a means of dynamically controlling loading conditions in vitro. This dynamic tissue loading platform consists of a thin magnetoresponsive hydrogel cantilever on which 2D engineered myocardial tissue is cultured. Exposing the cantilever to an external magnetic field-generated by positioning magnets at a controlled distance from the cantilever-causes the hydrogel film to stretch, creating tissue load. Next, cell contraction is induced through electrical stimulation, and the force of the contraction is recorded, by measuring the cantilever's deflection. Force-length-based measurements of contractility are then derived, comparable to clinical measurements. In an illustrative application, the platform is used to measure contractility both in untreated myocardial tissue and in tissue exposed to an inotropic agent. Clear differences are observed between conditions, suggesting that the proposed platform has significant potential to provide clinically relevant measurements of contractility.