Staci Horme

STEMart, a US-based provider of comprehensive services for all phases of medical device development, recently announced its the launch of its comprehensive Flow Cytometry Services to meet the diverse needs of research, diagnostics, and clinical studies, offering scientists and clinicians access to powerful tools for detailed cellular analysis, including cellular functions, phenotypes, and molecular interactions. Flow cytometry is a technique for rapid multiparameter analysis of single cells in solution. It uses a laser as a light source to produce scattered light and fluorescence signals that are read by a detector such as a photodiode or photomultiplier tube. These signals are converted into electronic signals that are analyzed by a computer and written to a standard format (.fcs) data file. Cell populations can be analyzed and purified based on their fluorescence or light scattering characteristics. A variety of fluorescent reagents are utilized in flow cytometry. These ... Continue reading →

STEMart introduces Balloon Catheter Testing Services for the development of safe and effective medical devices. STEMart, a US-based provider of comprehensive services for all phases of medical device development, announces the expansion of its medical device testing capabilities and introduces Balloon Catheter Testing Services for the development of safe and effective medical devices. These reliable testing solutions will meet the evolving needs of the medical device industry and help manufacturers minimize the compliance risks. Medical device testing is a crucial step in the development and commercialization of innovative medical devices. To ensure product safety and efficacy, comprehensive testing is required throughout the entire product lifecycle. STEMart’s experienced team assists clients in meeting stringent regulatory standards, including ISO 10992, ISO 18562, FDA guidance, and ASTM standards. By providing a range of testing services for Class I, II, and III ... Continue reading →

STEMart proudly announces the launch of its new Medical Device Prototyping Services. STEMart, a US-based provider of comprehensive services for all phases of medical device development, proudly announces the launch of its new Medical Device Prototyping Services. Using the latest technologies, these reliable prototyping solutions can help medical device companies streamline the development process and test new products quickly and cost-effectively, saving time and resources. Prototyping is the process of creating a primary version of a product for visualization and conceptualization. In general, prototypes fall into two main categories: functional and non-functional. Functional prototypes give people an idea of the basic form and function of a product. Non-functional prototypes are used to provide people with a non-digital representation of the product. In the case of medical device prototyping, a functional prototype is not a prototype that can be used in the marketplace because ... Continue reading →

What is Antibiotic Potency Test? A microbiological potency assay measures the bioactivity or potency of an antibiotic by the degree of growth repression on susceptible microorganisms at different concentrations. All antibiotic products must go through potency testing prior to market release. Both the EP and the USP require testing of antibiotic potency using microbiological assays for some products. Compared with measuring the potency of an antibiotic chemically, assessing the potency of an antibiotic microbiologically verify the ability of the antibiotic to destroy the selected organisms and the concentration at which the antibiotic will work effectively. And one major advantage of microbiological potency testing is that it can measure the effectiveness of the antibiotic directly on a living microorganism. Testing Methods Typically, antibiotic products have their potency determined by comparison with a standard substance or a biological reference substance. Such potency is expressed ... Continue reading →

Biocompatibility evaluation of breathing gas pathways in medical devices is a powerful tool for the evaluation of contaminants from the air emitted from the device for Volatile Organic Compounds (VOCs) and particulate matter when the gas pathway is intended to contact a patients’ respiratory tract. Standard for Biocompatibility Evaluation of Breathing Gas Pathways in Medical Device "Chemical Characterization of medical device materials", part eighteen of the Biological evaluation of medical device standards(ISO 10993-18), gives out the general guidance for E/L testing including polar, semi-polar, and nonpolar solvents measure leaching of organic compounds. It also outlines that VOCs can be determined either by an analysis of aqueous extracts or direct analysis of test articles by heated headspace. ISO 18562, the standard for biocompatibility evaluation of material or medical device with a breathing gas pathway, presents instructions for E/L extraction with ... Continue reading →

The biocompatibility systemic toxicity tests are in vivo systemic tests used to evaluate the impairment or activation of a system, rather than the impairment of individual cells or organs. Acute systemic toxicity tests and pyrogenicity tests are included in the systemic toxicity tests. Acute Systemic Toxicity Testing Acute toxicity is considered to be the adverse effects that occur after administration of a single dose or repeated doses of a test article given within 24 hours. Acute systemic toxicity test determines the systemic toxic effect followed by a single acute exposure of medical biomaterials to the body. The acute systemic test can provide extensive instruction on health hazards which may be induced by acute exposure from a medical device or chemical material. The animals are administrated with test material extracts or the liquid chemical; subsequently, observed at 24 ± 2, 48 ± 2, and 72 ± 2 hours for signs of toxicity. Pyrogenicity Testing ... Continue reading →

The Biocompatibility Subacute and Subchronic Toxicity test is used to evaluate the toxicity effects likely to arise from repeated exposures would have on a patient, including any compound toxicity effects. This test determines the systemic effect of repeated doses of materials or their extracts for no less than 24 hours and no greater than 10% of the total lifespan of the test animal. Subacute toxicity (repeat-dose toxicity) focuses on adverse effects occurring after a single or repeated exposures to a test material per day during a period of 14 to 28 days. Subchronic toxicity indicates the adverse effects of a substance resulting from repeated exposure to a toxic agent over a period of several weeks or months. The subacute and subchronic toxicity studies include full clinical pathology (clinical chemistry, hematology, and coagulation), necropsy and organ weights, as well as histopathology. These tests can either be conducted with full histopathology or limited tissue evaluation. ... Continue reading →

Chemical Characterization is a powerful methodology for addressing biocompatibility endpoints, providing a risk assessment of biocompatibility using chemical, biocompatibility, and patient exposure data. Chemical Characterization involves the extraction of the device with various solvents, chemical analysis of compounds extracted from the device, and an evaluation of the toxicological risk associated with the patient exposure to the extracted compounds. Standard for Chemical Characterization "Chemical Characterization of materials", part eighteen of the Biological evaluation of medical devices standards (ISO 10993-18), gives out the general considerations for the analytical approach including the intended use of device contact time (blood, mucosal, skin contact), material composition, and surface area calculations. It also outlines for the extractables, the study design, solvents, temperature, and duration should be taken into account; while for the leachables, the drug ... Continue reading →

Sensitization testing is used to assess the potential of chemicals and medical devices to cause a delayed hypersensitivity reaction following a single or repeated exposure to the body. Sensitization is one of the three most common biocompatibility tests required to ensure the safety of medical devices. "Tests for irritation and skin sensitization", part ten of the Biological evaluation of medical devices standards (ISO 10993-10), gives out the general considerations that should be taken into account when evaluating the potential of inducing sensitizing of a medical device. It outlines the procedure of studies to assess the potential of medical devices and their constituent materials to induce irritation and skin sensitization. General Procedures of the Sensitization Test Exposing the animals to the test materials or extracts across multiple induction phases and a single challenge phase; Observing the challenge sites for about 24 and 48 hours after the removal of the ... Continue reading →

Irritation represents local tissue inflammation response to chemicals, without a systemic immunological component, and irritation is characterized by inflammation, redness, swelling, heat, or pain. Irritation testing is used to assess the potential of a medical device to cause an immediate irritation reaction in the skin, mucosal, or ocular tissues following a single or repeated exposure to the body. Irritation is one of the three most common biocompatibility tests required to ensure the safety of medical devices. Standard for Irritation Testing Irritation testing is instructed by FDA regulations and international standards. “Assessing the Irritation and Sensitization Potential of Transdermal and Topical Delivery Systems for ANDAs”, introduced by the FDA as guidance for industry, provides guidance for the design and carry out of studies to assess the potential of in vivo skin irritation and sensitization induced by a medical device. “Tests for irritation and ... Continue reading →

Genetic toxicology testing evaluates the potential of the test material to induce the gene mutation or chromosome damage using a range of bacterial, mammalian cells in vitro and in vivo test systems. STEMart offers multiple test types for genotoxicity biocompatibility testing, following the OECD guidelines modified for medical devices and performing under GLP conditions. Genetic Toxicology Testing for Medical Devices Fig.1 Ames test procedure. The mouse lymphoma assay is used to detect a battery of cell cultures, usually mammalian, to determine gene mutations, change in chromosome structure, and other gene toxicities induced by medical devices or extracts. This test can help eliminate the risk of eliciting genotoxicity for medical devices that have prolonged contact with patients. The chromosomal aberration test is used to evaluate the potential of a medical device compound to cause structural chromosomal abnormalities, this test can be performed in HPBLs ... Continue reading →

  Hemocompatibility testing is designed for medical devices contacting circulating blood. Biomaterials that contact blood could have cellular effects and humoral effects including thrombosis, embolism, activation of the coagulation, etc. For devices contacting with circulating blood, hemocompatibility testing is generally required as a biocompatibility assessment. STEMart offers multiple test types for Hemocompatibility biocompatibility testing including hemolysis, in vitro coagulation, in vivo thrombogenicity, and complement activation following the biocompatibility guidelines modified for medical devices. Hemocompatibility Testing for Medical Devices Fig. Schematic representation of major reactions in blood induced by biomaterial surface. (Weber, 2018)   · Hemolysis Test The hemolysis (plasma hemoglobin) test is regarded as an especially significant screening test to perform in biomaterials of a medical device that have direct or indirect ... Continue reading →

  Cytotoxicity testing is a sensitive method to assess the biocompatibility of a material extracted through a specific cell culture media following exposure of the extracted fluid to L929 cells. This test is performed on raw materials in the manufacturing process, all medical devices contacting patients, and devices undergoing a sterilization validation. STEMart provides a wide range of in vitro cytotoxicity assays to qualitatively and quantitatively evaluate the ability of medical device to damage cells or tissues. Qualitative Methods Extraction Method/ MEM Elution In Minimum Essential Medium (MEM), extract the leachable of a medical device for 24 hours. An extract is then placed over the L929 cells. The cells are examined microscopically for morphological changes, degeneration, and lysis of the cells following incubation.   Fig. 1 Qualitative cytotoxicity test with MEM elution. Agar Diffusion/ Agarose Overlay Assay In this method, a thin layer of ... Continue reading →