SILICA GEL 60 F254 25 TLC ALUMINIUM SHEE

Thin layer chromatography (TLC) plates are flat surfaces coated with a stationary phase adsorbent typically silica gel, aluminium oxide, or cellulose on a rigid or flexible backing of glass, aluminium, or plastic. In a TLC experiment, a small sample is spotted near the bottom of the plate, which is then placed in a developing tank containing a liquid mobile phase. The mobile phase travels up the plate by capillary action, carrying the sample components with it at different rates according to their polarity and affinity for the stationary phase. Each component separates into a distinct spot, which can be visualised under UV light or with chemical staining reagents.

Thin layer chromatography plates are among the most widely used consumables in analytical chemistry chosen for their speed, low cost, versatility, and ability to screen multiple samples simultaneously on a single plate.

The tlc plate Merck Silica Gel 60 F254 is the most widely referenced product in this category across pharmacopoeial methods, research publications, and laboratory SOPs. Their dominant market position is the result of over five decades of consistent quality, a standardised production process, and a layer surface that sets the benchmark for separation reproducibility. 

Silica Gel 60 — why it is the standard 

Silica Gel 60 refers to silica with an average pore diameter of 60 Å and a mean particle size of 10–12 μm. This combination delivers a uniform and highly dense coating with narrow chromatographic bands, low background noise, and excellent plate efficiency. The polymeric binder used in Merck plates — rather than the traditional gypsum (CaSO₄) binder — produces a surface that will not crack, blister, or crumble during development. It can withstand writing with a pencil, cutting with scissors, and exposure to aggressive reagents without damaging the layer, making it the preferred choice for derivative reaction sequences and densitometric scanning. 

F254 fluorescent indicator — UV detection at 254 nm 

The F254 designation indicates the plate contains an inorganic green-fluorescing indicator that is excited at 254 nm UV light. When the developed plate is viewed under a 254 nm UV lamp, the background glows green and any compound that absorbs UV at this wavelength appears as a dark spot — a phenomenon called fluorescence quenching. This allows detection of the majority of UV-absorbing organic compounds without any chemical staining, making F254 plates the standard choice for routine TLC in pharmaceutical, organic chemistry, and natural product laboratories. 

Aluminium backing — key advantages 

The aluminium sheet format offers specific practical advantages over glass-backed alternatives. Aluminium sheets are flexible and can be cut with scissors to any size required — a single 20×20 cm sheet can be cut into multiple smaller plates to reduce cost per analysis. Aluminium sheets are lighter than glass, less fragile, and easier to store in bulk. They are also more suitable for direct application of heat — using a hot plate or heat gun for derivatisation reagents — without the risk of thermal cracking that glass plates carry. 

Sample application 

Spot samples at a distance of 1.5–2 cm from the bottom edge of the plate, using a glass capillary, micropipette, or spotting device. Keep spot diameters small ideally 1–2 mm by applying small volumes and allowing each application to dry before re-spotting. Allow the plate to dry completely before development. Mark the origin line and solvent front with a pencil before development do not use pen, as most inks will run with the mobile phase. 

Mobile phase selection 

Mobile phase selection determines separation quality. For non-polar and moderately polar compounds on silica (normal-phase TLC), start with a non-polar solvent such as n-hexane and increase polarity by adding ethyl acetate, acetone, or 2-propanol until adequate resolution is achieved. A commonly used starting system for most organic compounds is n-hexane:ethyl acetate (7:3 v/v). For more polar compounds, reverse the ratio or switch to dichloromethane:methanol systems. Always prepare fresh mobile phase on the day of use and saturate the developing tank with solvent vapour for at least 10 minutes before placing the plate. 

Development and detection 

Place the plate in the developing chamber with the mobile phase level below the spotting line. Allow development until the solvent front reaches 1.5–2 cm from the top of the plate, then remove and immediately mark the solvent front. Allow the plate to dry completely in a fume hood. View under a 254 nm UV lamp to visualise UV-absorbing compounds. For non-UV-absorbing compounds, apply a chemical staining reagent appropriate to your analyte class vanillin, ninhydrin, KMnO₄, or cerium sulphate, for example followed by heat activation on a hot plate. 

• Pharmaceutical QC — purity checks, identity testing, and related substances analysis of APIs and intermediates 

• Organic synthesis — reaction monitoring to track starting material consumption and product formation 

• Natural product screening — profiling of plant extracts, essential oils, and herbal preparations 

• Food and beverage analysis — detection of dyes, preservatives, and adulterants 

• Teaching and academic labs — demonstration of chromatographic separation principles 

• Preparative TLC — isolation of small quantities of pure compounds from complex mixtures (cut and elute from band) 

• Pesticide residue analysis — rapid screening of environmental and agricultural samples 

Lab Chemicals is an authorised distributor of Merck products in India, supplying pharmaceutical manufacturers, research institutions, NABL-accredited laboratories, and university departments across the country for over three decades. We stock Merck TLC plates including the Silica Gel 60 F254 aluminium sheet format with short lead times and reliable batch availability. Each order is supplied with the Merck Certificate of Analysis and SDS documentation. Our team can advise on plate format selection, mobile phase systems, and detection reagents for your specific application. We also supply a complete range of TLC mobile phase solvents including  

n-hexane for HPLC and 2-propanol for HPLC, so your TLC consumables and mobile phase solvents can be sourced from a single supplier with consistent grade and documentation standards.