Materials Module Flashcards
Biosensors
Analyte –> Bioreceptor –> Transducer –> Signal Processing
Invasive Medical Device
intended to come into contact with the surface of the eye or penetrate the body, either through a body orifice or through body surface
Non-invasive Medical Device
is not inside the body
Active Device
depends for its operation on a source of energy generated by the human body or gravity.
MDL (Medical Device Licenses)
required for all Class II, III, IV devices
MDEL (Medical device establishment licences)
issued to companies that import Class I-IV, distribute Class I-IV or manufacture Class I medical devices
ISO Standards
ISO creates documents that provide requirements, specifications, guidelines, or characteristics that can be used consistently to ensure that materials, procedures, process, and services are fit to their purpose.
ASTM Standards
ASTM develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems and services
Difference between ISO and ASTM
ASTM are generally part of ISO, ISO gathers standards from all countries
In Vitro Testing
studies that are done in the lab, which uses matter from living organisms
In Vivo Testing
studies done in the living body of an organism, must comply with ethical standards
Tests for In Vitro Toxicity
evaluate by:
- assessment of cell damage by morphological means
- measurements of cell damage and growth
- measurements of specific aspects of cellular metabolism
MTT Assay
- cells convert color to purple and the conversion amount can be measured by fluorescence
more purple means more cells
VEGF
a signalling protein that triggers the formation of blood vessels
VEGF antibody, is used to treat ROP
VEGF for Bone Regeneration
prescence of VEGF can drive osteoblasts to a location for bone regeneration
Tricking the body to produce VEGF
in hypoxia(absence of oxygen) VEGF production increases
Drug Delivery
controlling of transport and release of therapeutic agent inside body at particular rate and location
Diffusion
controlled by drug-material interaction and environment
Pediatric Medical Devices
market size is usually smaller, the growth rate of infants and children causes changing needs, and devices should encourage safety and durability
Examples of Pediatric Medical Devices
blood contacting devices such as catheters, heart valves, congenital heart defects and closure devices
Ophtalmic Biomaterials
contact lenses, corneal inlays or onlays, intraocular lenses, glaucoma shunts, vitreous replacements
materials commonly used include: polymethyl methacrylate, silicone, hydrogels, polyvinylidene fluoride
Tissue Engineering
Applications: skin, cartilage, bone, heart patches, blood vessels, eye
Xenogeneic Cell Source
different species, compatibility issues - concerns for animal virus transmission
Allogenic Cell Source
Same species, better compatibility, need for immune acceptance engineering
Autologous
From the patient, lower risk of rejection, timely, and potentially costly not good for off the shelf availability
Stem Cells
Pluripotent means that it gives rise to all the cell types that make up the body
Multipotent means develop into more than one cell type, but are limited
Cell Lines
Derived from sources where mutations or abnormalites allow them to continually divide and have infinite replicative capacity
CRISPR-Cas9
a genome editing technique that targets a genetic sequence and cuts it
Process of CRISPR-Cas 9
RNA molecule has corrected DNA string attached, and the guide RNA is attached to CAS9 cutting protein and goes to the mutation, the nutation is removed and corrected sequence is inserted
