Overview of Immunoassays and Biological Assays

Assay

Analytic procedure for measuring analyte presence.

Absorbance Measurement

Measure absorbance 15-45 seconds post substrate addition.

ELISA

Technique using immunosorbent for antigen or antibody.

Microtiter Plate

Wells coated with antibody for assays.

Chemical Assay

Study of chemical components in materials.

Incubation

Process of maintaining conditions for reactions.

Immunoassay

Technique identifying specific antigen or antibody.

Bioassay

Assessment of biological activity of substances.

Substrate Addition

Adding para nitrophenyl phosphate for color reaction.

Enzyme Immunoassay

Assays measuring enzyme-labeled antigens or antibodies.

Homogeneous EIA

Single-step test without separation of fractions.

Heterogeneous EIA

Requires separation of free and bound fractions.

HIV Detection

Use of ELISA for identifying HIV presence.

Infectious Disease Testing

ELISA detects various infectious disease antibodies.

Rotavirus Detection

Identifying rotavirus in fecal specimens.

Mycobacterial Antibody Detection

ELISA used for tuberculosis antibody identification.

Fluoroimmunoassay

Technique using fluorescence to detect antibodies.

EIA Advantages

Rapid, cost-effective, specific, and sensitive assays.

EIA Disadvantages

Species-specific, potentially less cost-effective.

Fluorescence

Light absorption and emission at different wavelengths.

Alkaline Phosphatase

Enzyme used for labeling in immunoassays.

Antibody Identification

Performed on blood serum to detect specific proteins.

Enzyme Multiplied Immunoassay Technique

Uses enzyme-bound drugs to identify analytes in samples.

Absorbance Measurements

Taken at intervals to assess enzyme reaction speed.

Fluorescent Dye

Used for visualization, e.g., fluorescein isothiocyanate.

Direct Immunofluorescence

Staining cells with antibodies linked to fluorochrome.

Clinical Specimen Analysis

Determining bioanalytes using immunoassay methods.

Chemiluminescence Detection

Light emission used in chromatography and electrophoresis.

Indirect Immunofluorescence

Involves secondary antibodies for enhanced detection.

Sensitivity of Chemiluminescent Assays

Comparable to Enzyme Immunoassay (EIA) and Radioimmunoassay (RIA).

UV Light Detection

Used to visualize bound secondary antibodies post-washing.

Reagent Efficiency

Minimal reagent use makes assays cost-effective.

Turnaround Time

High-speed detection leads to quicker results.

False Results Risks

Precision issues can lead to inaccurate outcomes.

Optical Immunoassay (OIA)

Based on antigen-antibody interactions on inert surfaces.

Luminescence

Generic term for light production processes.

Specific Binding Effect

Increases reactant thickness, alters reflected light color.

Chemiluminescence

Light emission during chemical reactions, often oxidation.

Bioluminescence

Biological chemiluminescence enhanced by catalyst proteins.

Chip Incubation Procedure

Involves mixing samples and antibodies, followed by rinsing.

Chemiluminescent Immunoassay

Uses luminescent labels for high-performance analysis.

Oxidation Reaction

Chemical reaction causing light emission in assays.

Monoclonal Antibody Coating

Coating wells with specific antibodies for testing.

HRP Labeled Antibody

Horseradish peroxidase used for signal amplification.

Conjugate

Combination of antigen and antibody for detection.

Chemiluminescence reagent

Substance that emits light during a chemical reaction.

Luminometer

Device measuring light intensity in assays.

Radioimmunoassay (RIA)

Technique using radiolabeled antigens for detection.

Antigen-antibody reaction

Binding of antigen to specific antibodies.

Radiolabeled antigen

Antigen tagged with radioactive isotopes.

Biological assay

Testing method estimating drug concentration biologically.

Well plates

Plates with multiple wells for assay reactions.

Calibrator

Known concentration used for comparison in assays.

Active constituent

Component responsible for biological activity in drugs.

Gamma counter

Device measuring radioactivity in samples.

Scintillation counter

Instrument detecting radiation from scintillation events.

Ethical considerations

Guidelines for humane treatment of live organisms.

Blood bank screening

Testing blood for infectious diseases like hepatitis.

Tumor marker

Substance indicating presence of cancer.

Peptic ulcer diagnosis

Identifying ulcers in the digestive tract.

Growth hormone measurement

Assessing levels of growth hormone in blood.

Insulin

Hormone regulating blood sugar levels.

Aflatoxins

Toxins produced by certain fungi in food.

Pharmacological action

Biological effect of a drug on the body.

Aflatoxins

Carcinogenic compounds requiring mandatory contamination monitoring.

Bioassays

Comparative tests against a standard drug for efficacy.

High specificity

Minimizes interference from other substances in assays.

Pharmacological response

Reproducible effects under identical testing conditions.

High sensitivity

Detects few picograms of antigen with affinity antibodies.

High precision

Consistent results across multiple assay repetitions.

Accuracy limits

Defines acceptable deviation from true value in assays.

Good accuracy

Within ± 20% of the true value.

Excellent accuracy

Within ± 10% of the true value.

Dependency factors

Dose size and drug intensity affect biological testing.

Variability in response

Different effects in animals versus humans in assays.

Tachyphylactic responses

Rapid decrease in response to a drug over time.

Potency

Amount of drug needed for a specific effect.

Affinity

Strength of binding between drug and target.

Efficacy

Ability of a drug to produce a desired effect.

Qualitative bioassays

Assess physical effects that are not quantifiable.

Quantitative bioassays

Determine concentration and potency of substances.

Specificity of compounds

Effectiveness against specific bacteria types, e.g., penicillin.

Complex compounds

Bioassays estimate substances like Vitamin B-12 effectively.

Animal testing

Utilizes various species for biological assay validation.

Standard drug

Reference substance for comparative bioassay testing.

Therapeutic property

Desired health benefit from a drug's pharmacological action.

Experimental design expertise

Required for accurate execution and analysis of assays.

Environmental standards

Maintaining conditions affecting public health and well-being.