GFAS

Q: Detection limits depend on the element and matrix. GFAS is generally very sensitive for many metals, but achievable limits are always matrix- and method-dependent.

GFAS is typically one element at a time , so multi-element requests are handled as a panel of separate measurements.

Q: Should I choose GFAS or ICP-MS?

If you need a small list of metals and high sensitivity, GFAS can be a strong fit. If you need many elements or very low limits across a broad panel, ICP-MS is usually more efficient.

What Is GFAS (GFAAS)?

GFAS (Graphite Furnace Atomic Absorption Spectroscopy), also called GFAAS, is a trace elemental analysis technique used to measure specific metals at very low concentrations. It introduces a small volume of sample into a graphite furnace that heats through controlled steps (drying, ashing, atomization). A light beam at an element-specific wavelength passes through the atomized cloud, and the amount of light absorbed is used to quantify the target element.

GFAS is especially useful when you need high sensitivity for a limited set of elements, have small sample volume, or need a robust method for challenging matrices (project-dependent).

Key advantages

Excellent sensitivity for selected metals (element-dependent)
Very small sample requirement (µL-level injections, project-dependent)
Strong for targeted analysis when you don’t need a full multi-element panel
Controlled furnace steps help manage matrix interferences (project-dependent)

What GFAS Is Used For

GFAS is commonly used for targeted trace metals such as:

Pb, Cd, As, Se, Hg (Hg may use dedicated approaches; project-dependent)
Cu, Ni, Cr, Mn, Fe, Zn (as needed, element/matrix dependent)
Metals that are critical for regulatory compliance or product quality (project-dependent)

Typical goals include:

Compliance and spec support for targeted metals
Incoming QC of raw materials and process chemicals (project-dependent)
Contamination troubleshooting when a specific metal is suspected
Verification testing for disputes or third-party confirmation

Why GFAS (vs. ICP)?

Teams choose GFAS when:

Only a few elements matter (targeted list)
You need high sensitivity without running a full panel
Sample volume is limited, and digestion/dilution must be minimized (project-dependent)
The matrix benefits from furnace-based interference management

However:

GFAS is usually one element at a time, so it can be slower for large element lists.
For ultra-trace multi-element requirements, ICP-MS is often more efficient.

Sample Types We Support

GFAS can be applied to many sample types (project-dependent), including:

Water and aqueous solutions: process water, rinse water, extracts
Chemicals and formulations: acids, salts, cleaning products (matrix dependent)
Food and consumer-product extracts (project-dependent)
Environmental-style samples (project-dependent)
Digested solids: when solids require acid digestion prior to metals testing

Best practice: include a reference/control sample for “what changed?” comparisons.

Typical Workflows

Targeted Metals Panel (Most Common)

Best for: QC release, compliance, supplier qualification

Define target element list + required limits
Choose calibration and QC plan (standards, blanks, spikes—scope-dependent)
Report results with pass/fail vs your spec (if provided)

Single-Element Confirmation

Best for: suspected contamination (e.g., Pb or Cd excursion)

Rapid targeted confirmation at low levels
Optional repeat testing or matrix spike recovery (project-dependent)

Comparative Study (“What Changed?”)

Best for: supplier changes, process excursions

Run the same targeted list on reference vs suspect
Summarize deltas and likely significance

What You Receive

Results table with concentration, units, and reporting limits
QC notes (blanks, calibration, recoveries—scope-dependent)
Comparison summary (reference vs suspect) highlighting key differences
Practical conclusions and recommended next steps (when used for investigations)

Sample Submission Guidelines

Please provide

Sample matrix description and hazards (SDS)
Target elements and required limits/specs
Sample volume available and any preservation details (if applicable)
Lot/batch IDs and reason for testing (QC, compliance, troubleshooting)
Reference/control sample whenever possible

Typical sample amounts

Liquids: 10–50 mL (often sufficient for repeats/QC)
Solids: project-dependent (may require digestion; provide enough for prep and repeats)

Packaging tips

Use clean containers (trace-metal grade if possible)
Avoid metal caps/liners when trace metals are critical
Label clearly (reference vs suspect, sample point/time)

FAQs

How low can GFAS detect metals?

Detection limits depend on the element and matrix. GFAS is generally very sensitive for many metals, but achievable limits are always matrix- and method-dependent.

Detection limits depend on the element and matrix. GFAS is generally very sensitive for many metals, but achievable limits are always matrix- and method-dependent.

GFAS is typically one element at a time, so multi-element requests are handled as a panel of separate measurements.

Should I choose GFAS or ICP-MS?

If you need a small list of metals and high sensitivity, GFAS can be a strong fit. If you need many elements or very low limits across a broad panel, ICP-MS is usually more efficient.

Is sample digestion required?

For water-based samples, often no. For solids and complex matrices, digestion or matrix preparation may be required (project-dependent).

Have additional questions?