Machinery Masters is a marketplace for new and used densitometers, the instruments that measure density and optical density across quality control, research, and process laboratories. The category covers two families: density meters that determine the density and specific gravity of liquids, and optical densitometers that measure the light absorbance of spots and bands, such as thin-layer chromatography plates and electrophoresis gels.

Both deliver the precise, repeatable measurements that pharmaceutical QC, beverage and chemical processing, and analytical laboratories rely on. Buyers include QC and analytical chemists, process and beverage technologists, and procurement teams sourcing validated laboratory equipment. Browse verified sellers to compare measurement type, accuracy, software version, condition, and price before you buy.

Shop Densitometers by Type

Densitometers are available across liquid-density measurement and optical densitometry in benchtop, portable, and automated formats. Selecting the correct type keeps the measurement principle, accuracy, and sample format matched to what you test. The main differences between configurations relate to whether the instrument measures liquid density or optical absorbance, its accuracy class, and whether it is a portable, benchtop, or automated system.

Digital (Oscillating U-Tube) Density Meters

Digital density meters measure liquid density by oscillating a small U-shaped tube filled with a sample and reading its resonant frequency, giving fast, accurate density and specific gravity from a tiny volume. Temperature-controlled and highly precise, they are the standard for pharmaceutical, beverage, and chemical density measurement in the laboratory.

Portable Density Meters

Portable density meters bring oscillating-tube measurement to the production floor, warehouse, or field, delivering laboratory-grade density and concentration results at the point of need. They suit at-line checks and incoming-goods testing where sending samples to a central laboratory would slow the process down.

Benchtop Laboratory Density Meters

Benchtop density meters provide high-accuracy density and specific gravity measurement with sample changers and temperature control for routine and high-throughput laboratory work. They anchor QC benches where consistent, documented density results are required across many samples.

TLC and Optical Densitometers

Scanning densitometers measure the optical density of separated zones on thin-layer chromatography plates, converting spot intensity into quantitative results. They are central to quantitative TLC and HPTLC analysis in pharmaceutical, herbal, and food laboratories, where separated compounds must be measured directly on the plate.

Gel and Blot Densitometers

Gel and blot densitometers quantify the intensity of bands on electrophoresis gels and western blot membranes, turning a visual result into numerical data. They support protein and nucleic acid analysis where relative band intensity must be measured accurately and reproducibly.

Specific Gravity and Concentration Meters

Specific gravity and concentration meters use density measurement to report application-specific values such as alcohol content, sugar concentration, or acid strength. Widely used in beverage, chemical, and food production, they convert precise density into the concentration parameters those industries control.

Densitometers Brands on Machinery Masters

Machinery Masters lists densitometers from established density and analytical instrument manufacturers, so you can source a specific make and model or compare comparable instruments across sellers.

Anton Paar
Mettler-Toledo
Rudolph Research Analytical
Kyoto Electronics
KRUSS
CAMAG
Bio-Rad
Sartorius
Hach
Atago

Densitometers Applications and Uses

Densitometers are deployed across pharmaceutical, beverage, chemical, and research settings wherever density or optical density must be measured accurately and repeatably. Requirements depend on the sample type, the accuracy needed, and the accreditation framework the laboratory works within.

Pharmaceutical Quality Control

Pharmaceutical QC laboratories use density meters to measure the density and specific gravity of solutions, syrups, and active ingredients as a critical quality attribute in in-process and release testing. Accurate, documented density results support the validated data that release decisions require.

Beverage, Chemical, and Concentration Measurement

Beverage, chemical, and food producers use density and concentration meters to determine alcohol content, sugar concentration, and acid strength during production. Fast, precise density measurement lets operators control concentration and consistency across batches.

Quantitative TLC and Chromatography

Analytical laboratories use scanning densitometers to quantify separated zones on thin-layer chromatography plates in pharmaceutical, herbal, and food testing. Direct on-plate measurement provides the quantitative data that qualitative separation alone cannot deliver.

Gel Electrophoresis and Blot Quantification

Research and biopharmaceutical laboratories use gel and blot densitometers to measure band intensity on electrophoresis gels and western blots. Reproducible densitometry turns visual results into quantitative data for protein and nucleic acid analysis.

Frequently Asked Questions

What is a densitometer and what does it measure?

A densitometer measures density, either the mass-per-volume density of a liquid or the optical density of a sample. Liquid density meters report density and specific gravity, which relate directly to composition and concentration. Optical densitometers measure how much light a spot or band absorbs, which relates to the amount of material present. The right type depends on whether you are measuring a liquid or a separated sample.

What is the difference between a density meter and an optical densitometer?

A density meter measures the physical density of a liquid, typically using an oscillating U-tube, and reports density, specific gravity, or a derived concentration. An optical densitometer measures light absorbance, quantifying the intensity of spots on a TLC plate or bands on a gel. In short, a density meter measures how heavy a liquid is per unit volume, while an optical densitometer measures how much light a sample absorbs.

How does a digital density meter work?

A digital density meter fills a small U-shaped glass tube with the sample and vibrates it. The tube's resonant frequency depends on the mass of the sample it contains, so measuring that frequency at a controlled temperature gives a precise density reading from a very small volume. The result can be reported as density, specific gravity, or an application-specific concentration.

What is a TLC densitometer used for?

A TLC densitometer scans a developed thin-layer chromatography plate and measures the optical density of each separated zone, converting spot intensity into quantitative results. It turns a qualitative separation into quantitative data, which is used for assay and impurity determination in pharmaceutical, herbal, and food analysis where compounds are measured directly on the plate.

What is the difference between new and used densitometers?

New densitometers arrive with a manufacturer warranty, current software, and full documentation. Used and refurbished instruments offer significant savings from reputable sellers with documented service history and clear provenance. For regulated use, plan to verify performance and, where needed, requalify the instrument against your specifications, and confirm software and service support before it enters service.

Where can I buy densitometers on Machinery Masters?

Browse Machinery Masters for new and used digital and portable density meters, benchtop laboratory density meters, TLC and optical densitometers, and gel densitometers from verified sellers worldwide. Use the search and filter tools to narrow by type, brand, and specification, then contact sellers directly to request calibration records, service history, and technical specifications before you buy.