Nickel Standard Solutions: Preparation, Uses & Quality

Nickel standard is a precisely formulated reference solution used to calibrate analytical instruments and verify the accuracy of nickel quantification across a wide range of environmental, biological, and industrial matrices.

Typical Concentration

1000 mg/L (1000 ppm) in dilute HNO₃ or HCl matrix

Primary Applications

AAS, ICP-OES, ICP-MS instrument calibration and method validation

Stability

Stable at room temperature in tightly sealed, acid-washed containers; typically 12–24 months when stored correctly

Matrix

Commonly prepared in 2–5% (v/v) HNO₃ to prevent hydrolysis and adsorption

SKU

N117583

Traceability

High-purity nickel salts or elemental nickel traceable to NIST or equivalent national metrology institutes

What Is a Nickel Standard Solution?

A nickel standard solution is a reference material containing a precisely known concentration of nickel ions dissolved in an acidic aqueous matrix. These solutions serve as the quantitative benchmark against which instrument response is measured during atomic spectrometric analyses, including flame atomic absorption spectrometry (FAAS), graphite furnace AAS (GFAAS), inductively coupled plasma optical emission spectrometry (ICP-OES), and inductively coupled plasma mass spectrometry (ICP-MS).

Stock standards are typically supplied at 1000 mg/L (1 g/L) and are diluted gravimetrically or volumetrically to prepare working calibration solutions in the low µg/L to mg/L range appropriate for the technique and expected sample concentration. The acid matrix—most commonly 2–5% HNO₃—prevents nickel from precipitating or adsorbing to container walls, ensuring long-term stability and accuracy.

Preparation and Certification of Nickel Standards

Certified nickel standards are manufactured from high-purity nickel metal or high-purity nickel salts (such as nickel nitrate or nickel sulfate). The starting material is dissolved in ultrapure nitric or hydrochloric acid, then diluted with ultrapure water (≥18 MΩ·cm resistivity) to the target concentration. Gravimetric preparation minimizes volumetric error and is preferred when the highest accuracy is required.

Certification typically involves independent analysis by two or more validated analytical methods, with results reported alongside expanded uncertainty at a 95% confidence level. Traceability to a national metrology institute—such as NIST (USA), PTB (Germany), or NIM (China)—is a key quality indicator. Certificates of Analysis (CoA) document lot-specific concentration values, uncertainty, expiry date, and storage conditions.

For laboratories operating under ISO/IEC 17025 accreditation, using certified reference materials (CRMs) traceable to SI units is mandatory for method validation and proficiency testing. Aladdin's Nickel Standard (SKU: N117583) is intended to support these rigorous quality requirements.

Applications in Analytical Chemistry

Instrument Calibration: Multi-point calibration curves constructed from serially diluted nickel standards establish the linear dynamic range of the instrument and convert raw signal (absorbance, emission intensity, or ion counts) into concentration values for unknown samples.

Environmental Monitoring: Regulatory methods for drinking water, wastewater, soil leachate, and air particulates—including US EPA Methods 200.7, 200.8, and 6010—require the use of certified calibration standards for nickel determination. Permissible limits for nickel in drinking water (e.g., WHO guideline of 0.07 mg/L) demand low-level standards in the µg/L range.

Industrial Quality Control: Electroplating baths, alloy production, battery manufacturing (nickel-metal hydride and lithium-ion cells), and catalysis industries routinely quantify nickel in process streams and finished products using ICP-OES or AAS calibrated with certified nickel standards.

Biomedical and Toxicological Research: Nickel is an established allergen and a suspected carcinogen. Biological monitoring of occupational exposure in urine, blood, and tissue samples relies on validated methods that use nickel standards for calibration.

Handling, Storage, and Best Practices

Storage: Store nickel standard solutions at room temperature (15–25 °C) in their original, tightly capped, acid-washed high-density polyethylene (HDPE) or fluoropolymer bottles, away from direct sunlight and incompatible materials such as strong bases or oxidizers. Do not freeze, as this can alter concentration through differential expansion.

Contamination Prevention: Use dedicated pipettes and volumetric glassware that have been rinsed with 5–10% HNO₃ followed by ultrapure water before use. Avoid contact with metal implements. Prepare working standards in polypropylene or Teflon vessels.

Dilution: Always dilute into a matching acid matrix to avoid matrix mismatch effects on instrument sensitivity. Document all dilution steps with balances or calibrated volumetric equipment traceable to national standards.

Safety: Nickel compounds are classified as possible human carcinogens (IARC Group 2B for soluble nickel compounds). Wear appropriate PPE—nitrile gloves, safety glasses, and lab coat—when handling. Dispose of nickel-containing waste in accordance with local heavy-metal waste regulations.

Selecting the Right Nickel Standard for Your Method

Choosing an appropriate nickel standard requires matching several parameters to your analytical method and regulatory requirements:

• Concentration: Stock standards at 1000 mg/L are versatile for preparing calibration curves across a wide range of techniques. Pre-diluted standards at 10 or 100 mg/L reduce preparation steps and associated error for routine work.
• Matrix compatibility: Ensure the acid type and concentration in the standard match or are compatible with your sample digest matrix to minimize matrix effects.
• Certification level: For regulated analyses (environmental, clinical, food), use CRMs with documented traceability. For in-house method development, high-purity single-element standards without full CRM certification may suffice.
• Multi-element vs. single-element standards: Multi-element standards can improve throughput when calibrating for several analytes simultaneously, provided the elements are mutually compatible in the chosen matrix.
• Volume and shelf life: Order quantities appropriate to usage rate to avoid working with expired material. Check the expiry date on the CoA before use.

Aladdin Scientific's Nickel Standard (SKU: N117583) provides researchers and quality professionals with a reliable, traceable reference material to underpin rigorous analytical workflows.

Frequently asked questions

What concentration of nickel standard should I use for ICP-OES calibration?

For ICP-OES, a typical calibration range for nickel is 0.1–10 mg/L, depending on the emission line selected and the expected sample concentration. Start with a 1000 mg/L stock standard (SKU: N117583) and prepare a series of working standards by serial dilution in a matching acid matrix (e.g., 2% HNO₃). Always include a blank and a mid-range check standard.

How should I store nickel standard solutions to maximize shelf life?

Store nickel standards in their original, tightly sealed HDPE or fluoropolymer bottles at room temperature (15–25 °C), away from light and heat sources. Do not freeze. Under these conditions, properly formulated nickel standards in dilute HNO₃ typically remain stable for 12–24 months. Always verify the expiry date on the Certificate of Analysis before use.

Can I use the same nickel standard for both AAS and ICP-MS?

Yes, a 1000 mg/L single-element nickel standard in dilute HNO₃ is generally suitable as a starting material for preparing working calibration solutions for both AAS and ICP-MS. However, the working concentration ranges differ significantly: AAS typically operates in the mg/L range, while ICP-MS works in the µg/L (ppb) range. Dilute accordingly, and for ICP-MS, consider using an appropriate internal standard to correct for matrix and instrumental drift.

What safety precautions are needed when handling nickel standard solutions?

Nickel compounds are classified as possible human carcinogens (IARC Group 2B for soluble compounds). Always wear nitrile gloves, safety glasses, and a lab coat when handling. Work in a well-ventilated area or fume hood. In case of skin contact, wash thoroughly with soap and water. Dispose of nickel-containing waste according to local regulations for heavy metal hazardous waste.

How do I verify the accuracy of my nickel standard once it is opened?

After opening, verify the standard by analysing a certified reference material (CRM) of known nickel concentration as an independent check standard. If the measured value falls within the accepted tolerance (typically ±5–10% of the certified value, depending on method requirements), the standard is performing acceptably. Also inspect the solution for discolouration, turbidity, or precipitation, which may indicate degradation or contamination.

References

1. US EPA Method 200.7: Determination of Metals and Trace Elements in Water and Wastes by Inductively Coupled Plasma-Atomic Emission Spectrometry. US Environmental Protection Agency, Revision 4.4, 1994.
2. US EPA Method 200.8: Determination of Trace Elements in Waters and Wastes by Inductively Coupled Plasma-Mass Spectrometry. US Environmental Protection Agency, Revision 5.4, 1994.
3. IARC Working Group. Nickel and Nickel Compounds. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Vol. 100C. International Agency for Research on Cancer, Lyon, 2012.
4. ISO/IEC 17025:2017. General Requirements for the Competence of Testing and Calibration Laboratories. International Organization for Standardization, Geneva, 2017.
5. World Health Organization. Nickel in Drinking Water. Background Document for Development of WHO Guidelines for Drinking-Water Quality. WHO/SDE/WSH/07.08/55, 2007.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.