Spectroscopy

Buying guide

Which part of the spectrum your method needs?

What settles a spectroscopy purchase first is not price or condition but the physics the method requires, because that decides the whole instrument class before any other factor comes into play. Elemental analysis at trace levels points to inductively coupled plasma, either optical emission or mass spectrometry, where detection limits reach parts per trillion. Molecular identification of organic compounds points to infrared or near-infrared. Concentration of a single element at higher levels is often adequate on an atomic absorption instrument, which costs far less than ICP. Optical rotation of chiral compounds needs a polarimeter and nothing else. A buyer who fixes the technique first can read every later specification, sample throughput, wavelength range, detector type, against a shortlist of instruments that can actually do the work, rather than comparing machines that answer different questions.

Once the technique is set, a used unit carries risks the datasheet does not show. Plasma-based instruments have torches, nebulisers and cones that wear and that a buyer should confirm are present and serviceable. Detector performance drifts over an instrument's life, so ask when the unit was last calibrated and against what standards. Optical benches can fall out of alignment in transit. For any used spectrometer, confirm that the control software runs on a current operating system, since legacy instruments are frequently tied to a computer the seller cannot replace. These checks matter more here than headline specifications, because a correctly specified instrument that arrives out of calibration still costs weeks before it produces usable data.

Price on this marketplace spans a wide band, and knowing where a technique sits in it helps a buyer set a realistic budget. A simple polarimeter occupies the low end; a research-grade ICP-MS occupies the high end near EUR 201.000. Across all listings the average sits at EUR 4.966, with the range running from EUR 45 to EUR 201.000. Refurbished units listed for sale are more affordable than new, which is why used instruments dominate this catalogue. The brands that recur most, Thermo, Thermo Scientific, Bruker, Thermo Fisher, Perkin Elmer, set the reference points: their instruments are widely documented, parts are easier to source, and a given model is simpler to compare across sellers than a rarely listed make. What a unit costs therefore tracks both the technique and the brand, and a buyer comparing two listings of the same model from different suppliers is comparing like with like, which the thinner end of the catalogue does not always allow.

Types of Spectroscopy

ICP and ICP-MS instruments

Inductively coupled plasma instruments ionise a sample in an argon plasma that reaches temperatures around 10,000 kelvin, then measure the light emitted (ICP-OES) or the ions themselves (ICP-MS). This is the largest spectroscopy subtype listed here and the technique of choice for multi-element analysis at trace and ultratrace levels. ICP-MS in particular reaches detection limits other elemental techniques cannot, which is why it anchors environmental testing, clinical toxicology and materials work. In the life sciences it does metallomics and trace-metal analysis of biological samples, and it is also used for quantifying metal-based labels in bioanalytical assays. Buyers of these units should weigh running costs alongside purchase price, since argon consumption and consumable cones add to the total.

Atomic absorption spectrometers

Atomic absorption spectrometry measures the light a free atom absorbs at a characteristic wavelength, giving the concentration of a single element per reading. It is older and narrower than ICP but considerably cheaper, and remains the practical choice where a laboratory needs one or a few elements rather than a full panel. Flame and graphite-furnace variants cover different concentration ranges, the furnace reaching lower levels at the cost of slower throughput. Atomic absorption instruments serve routine work in water testing, food analysis and clinical chemistry, and in the life sciences they support trace-element determination in biological fluids and nutritional analysis of cell culture media.

Infrared and FT-IR spectrometers

Infrared spectroscopy identifies molecules from the way their bonds absorb infrared light, producing a spectrum that acts as a chemical fingerprint. Fourier-transform infrared (FT-IR) instruments collect the whole spectrum at once and dominate the modern form of the technique. They identify organic compounds and polymers, verify raw materials and detect contaminants without destroying the sample. In molecular biology and biomanufacturing, FT-IR is used for protein secondary structure analysis and for monitoring bioprocessing in real time, and it also supports formulation work where the composition of a mixture has to be confirmed.

Polarimeters

A polarimeter measures optical rotation, the angle by which a chiral substance rotates the plane of polarised light. It is a specialised, lower-cost instrument with a narrow purpose: determining the concentration or optical purity of chiral compounds, which matters wherever a molecule's handedness affects its behaviour. Sugar analysis, essential-oil characterisation and pharmaceutical quality control are the common uses. In molecular diagnostics and pharmaceutical development, polarimetry confirms the enantiomeric purity of active ingredients, since the wrong enantiomer can be inactive or harmful.

NIR spectrometers

Near-infrared spectroscopy works in the spectral region between visible and mid-infrared light, where overtone and combination bands of molecular vibrations appear. Its strength is speed and minimal sample preparation, which makes it suited to rapid, non-destructive measurement of moisture, protein and fat content across large numbers of samples. NIR is widely applied in agriculture, food testing and pharmaceutical process control. In biomanufacturing it also supports at-line monitoring of cell culture and fermentation, where concentration of substrates and metabolites has to be followed without interrupting the run.

Across these subtypes the catalogue leans heavily toward used instrumentation. New, used and refurbished units are all listed, and 95 percent of the listings are used, with Thermo, Thermo Scientific, Bruker, Thermo Fisher, Perkin Elmer the makes that appear most often. Prices range from EUR 45 to EUR 201.000 depending on the technique and the instrument's capability.