DNA Detection Kit (Diphenylamine, Microplate Method)

Cat. No.: D1528830

GRADE & PURITY BioReagent

Overview

This kit is a diphenylamine microplate colorimetric assay for DNA quantification, including DNA standard solution, diphenylamine chromogenic reagent, and acetaldehyde enhancer solution. It is designed for the biochemical quantification of total DNA in research samples. Principle: Nucleic acid molecules release 2'-deoxyribose upon heating, which undergoes dehydration under acidic conditions to form ω-hydroxy-γ-ketopentanal. This product specifically reacts with diphenylamine reagent to generate a stable blue-colored compound. The chromogenic product exhibits a maximum absorbance at 595 nm. Within the DNA concentration range of 20–400 μg/mL, the absorbance shows a good linear correlation with DNA concentration (R² ≥ 0.99). The addition of trace amounts of acetaldehyde significantly enhances chromogenic sensitivity and reduces detection errors. This kit utilizes a microplate assay format, compatible with high-throughput microplate reader detection. It offers convenient operation and good reproducibility, and enables accurate calculation of sample DNA content via a standard curve. It is widely applicable for DNA quantification in animal and plant tissues, cells, and microbial samples. For research use only. Not for clinical diagnosis, food testing, or other non-research applications.

Specifications

Specifications & Purity

BioReagent

Grade

BioReagent

Storage and Shipping

Storage

Store at -20°C

Shipped In

Ice chest + Ice pads

Application Protocols

Validated, item-specific protocols are not provided in the Product Data. Please refer to the kit insert/manual for authoritative instructions.

General/literature workflow for a microplate DPA DNA assay (for context only):

• Preparation: Equilibrate reagents to room temperature if required by the protocol. Prepare a DNA standard curve in the same buffer as your samples. Use clear, flat-bottom plates compatible with visible absorbance.
• Loading: Pipette standards and samples (typically 10–50 µL) into wells; add the DPA reagent to a defined final volume (e.g., 100–250 µL). Mix gently by plate tapping or brief shaking; avoid bubbles.
• Incubation: Seal the plate and incubate at the specified temperature/time (literature: often elevated temperature). Ensure even heating; avoid evaporative losses.
• Reading: Cool the plate if required; read absorbance near 595–600 nm. Subtract blank and fit a standard curve (linear or polynomial if recommended by the method).
• QC: Include replicate wells; assess CVs and spike-recovery to verify matrix compatibility.

Notes:

• Do not substitute these general steps for the kit’s validated protocol. Exact reagent volumes, incubation parameters, and safety requirements are provided in the official documentation, not reproduced here.

Biological Roles

This kit does not contain biological macromolecules of intrinsic biological function; instead, it quantifies DNA via a chemical color reaction. Therefore, biological roles pertain to the analyte (DNA) rather than the kit itself.

General/literature context on the analyte (DNA):

• DNA stores genetic information in virtually all cellular life. Its backbone comprises 2-deoxyribose sugars linked by phosphodiester bonds, with nucleobases (A, T, G, C) that encode sequence information.
• The diphenylamine reaction leverages a chemical hallmark of DNA: the 2-deoxyribose sugar. Under acidic/thermal conditions, depurination and dehydration yield aldehydic intermediates that react with aromatic amines to form colored conjugated species. RNA (ribose) is less reactive under the same conditions, which underpins the assay’s relative selectivity for DNA (literature).
• In cell biology workflows, accurate DNA content measurements support normalization across samples (e.g., per-well DNA for proliferation indices) and enable tracking of extraction efficiencies.

Important boundaries:

• The kit is for research use only. It is not intended for clinical diagnostics, patient management, or any in vivo application.
• The chemistry reports bulk DNA content; it does not provide sequence, size distribution, integrity metrics, or base composition. Complementary methods (gel electrophoresis, fluorometric dyes, qPCR) should be used when those attributes are required.

Buffer Applications

This product is not a buffering reagent or a pre-formulated buffer system. Consequently, conventional buffer recipes and pH-range guidance are not directly applicable.

Practical notes (general/literature for DPA assays):

• DNA samples can be prepared in common low-ionic-strength buffers (e.g., TE or phosphate). Keep buffer components consistent between standards and samples to minimize matrix effects.
• Avoid high concentrations of primary amines (e.g., Tris at very high mM) and reducing sugars in the sample matrix, which can potentially influence color development. Validate your specific buffer composition with a spike-recovery experiment.

For detailed compatibility limits and any kit-provided diluents, consult the product’s manual/CoA. Those specifics are not provided here.

Green Alternatives

Environmental/health considerations for DPA assays (general): Traditional diphenylamine reactions often employ strong mineral acids and an aromatic amine, which can pose corrosivity, toxicity, and waste-disposal concerns.

Alternatives and trade-offs (literature):

• UV absorbance at 260 nm
  • Pros: No added reagents, minimal waste, rapid.
  • Cons: Poor selectivity vs. RNA, protein/turbidity interference, requires quartz optics.
• Fluorometric dsDNA dyes (e.g., PicoGreen-class)
  • Pros: High sensitivity and dsDNA selectivity at room temperature.
  • Cons: Cost, light sensitivity, dye disposal considerations; fluorescence readers required.
• HPLC quantitation of nucleosides after enzymatic digestion
  • Pros: High specificity and structural information.
  • Cons: Complex workflow, solvent consumption, and instrument time.
• Dische–DABA (p-dimethylaminobenzaldehyde) or Orcinol assays
  • Pros: Alternative colorimetric chemistries with varied selectivities.
  • Cons: Also rely on strong acids/aromatic aldehydes; hazard profiles differ but are not necessarily greener.

Greener practice within DPA workflows (general recommendations):

• Miniaturize to microplate scale to reduce reagent volumes and waste.
• Use secondary containment and segregate acidic organic waste for proper treatment.
• Optimize incubation to the minimal effective temperature/time window to reduce energy use and degradation byproducts.

Note: The specific composition and hazard/waste profile of this kit are not disclosed here; evaluate the SDS and your institution’s green-chemistry guidelines for best practices.

Pharmaceutical Uses

This kit is intended for research use only (from Product Data) and is not designed or validated for clinical diagnosis or therapeutic manufacturing.

General/literature context where analogous methods are applied in non-clinical pharma/QC settings:

• Bulk DNA content estimation in process development samples (e.g., assessing DNA carryover in upstream lysates) for internal research metrics.
• Normalization of DNA content in cell-based assay plates to compare proliferation or cytotoxicity readouts on a per-DNA basis.
• Teaching and method-development labs for colorimetric nucleic acid quantification.

Boundaries and compliance:

• No pharmacopeial monograph, excipient role, or cGMP validation is claimed or provided for this item.
• Any use in regulated environments would require independent method validation (specificity, linearity, accuracy, precision, robustness) under the applicable quality system.

For any application beyond exploratory research, consult your QA/compliance team. The product documentation (not included here) should be reviewed for performance characteristics and limitations.

Physical Properties

This is a multi-component kit; single-compound physical constants are not applicable to the kit as a whole. Item-specific physical specifications (e.g., solution concentrations, pH, stabilizers) are not provided here.

Item-specific data:

• Appearance: Not specified for this item; refer to CoA/Spec Sheet.
• Density/RI/UV cutoff: Not specified for this item; refer to CoA/Spec Sheet.
• Solubility (kit reagents): Not specified for this item; refer to CoA/Spec Sheet.

General/literature values (for context on the chromogenic chemistry, not specifications for this item):

• Diphenylamine (free base) MP ~52–54 °C; BP ~302–305 °C at 1 atm (literature). These values are for the neat compound and do not describe the formulated reagent solutions.
• Detection wavelength: The classical DPA-DNA chromophore exhibits a broad absorbance maximum around 590–600 nm (literature), which enables low background in protein-containing samples due to reduced protein absorbance in the red region.
• Matrix compatibility (literature): Aqueous buffers without strong nucleophiles or oxidants are generally compatible; detergents and high sugar backgrounds can interfere by altering color development or baseline.

Important: Use only the wavelengths, plate types, and incubation parameters recommended in the kit insert. Do not infer performance specifications from literature values; consult the kit protocol for validated measurement settings.

Quality and Grades

• Grade/Purity (from Product Data): BioReagent. This denotes suitability for biological research workflows, emphasizing low background in typical life-science assays and consistent lot-to-lot performance. It is not a clinical/diagnostic grade.

What BioReagent generally implies (context, not a specification):

• Controlled bioburden and low levels of common assay interferences, enabling reproducible color development in microplate formats.
• Batch-to-batch QC targeted at functional performance (e.g., linearity with DNA standards, plate-read signal stability) rather than analytical solvent-grade metrics.

Assay-focused quality considerations:

• Blank stability: Reagent blanks should remain low and stable during the specified incubation and read window. Acceptance limits, if any, are provided in the kit documentation (not specified here).
• Dynamic range: The microplate method typically supports sub-microgram to low-microgram DNA per well (literature). Actual validated range for this kit is not specified here; consult CoA/Spec Sheet.
• Interferences: RNA, free deoxyribose, and strong reducing sugars can contribute to background in DPA chemistry (literature). Kit-specific tolerances are not specified here.

Not provided for this item; refer to CoA/Spec Sheet:

• Stabilizers, preservatives, metal limits, UV cutoff, water content, and exact reagent concentrations.

Research use note (from Product Data): For research use only.

Reaction and Applications

Primary application: Colorimetric quantification of DNA in a microplate format using the diphenylamine (DPA) reaction.

General/literature basis of the method (Burton/Dische-type assay):

• Under strong acid and heat, DNA depurinates; the resulting deoxyribose is dehydrated to a reactive aldehydic species that condenses with diphenylamine to yield a blue carbocationic chromophore. Absorbance is measured typically near 595–600 nm.
• Selectivity: The assay preferentially responds to deoxyribose (DNA) over ribose (RNA), offering practical discrimination in mixed nucleic-acid samples (literature). Proteins show minimal direct absorbance at the detection wavelength, improving compatibility with crude lysates.

Use cases (research only):

• Estimating DNA yields from tissue, cell pellets, or environmental samples where UV A260 is compromised by turbidity or protein.
• High-throughput DNA content measurements in microplate readers for normalization (e.g., per-well DNA content in screening campaigns) and for monitoring acid hydrolysis/depurination studies.
• Historical/teaching labs illustrating carbohydrate–aromatic amine colorimetric chemistry.

Practical tips (literature-based):

• Standard curve with calf thymus or salmon DNA across the expected concentration range improves accuracy; match buffer conditions to samples.
• Include a no-DNA blank and, when RNA is present, consider RNase pretreatment to reduce background.
• Ensure uniform heating/time across wells; plate sealers or lids help mitigate edge effects during incubation.

Kit-specific performance characteristics and step-by-step instructions are not provided here; consult the kit manual/CoA.

Reaction Conditions

Kit-specific validated conditions are not provided here; defer to the kit protocol for authoritative instructions. The following is general literature guidance for microplate-adapted diphenylamine DNA assays and should be treated as context only:

• Reagent/sample ratio: Often 5–10 volumes of DPA reagent per volume of DNA sample to ensure excess chromogenic reagent (literature). Microplate wells typically contain total volumes of 100–300 µL.
• Incubation: Heating at elevated temperature to promote depurination/dehydration and color development. Classical tube methods use ~95–100 °C for 10–20 min; microplate adaptations may use sealed plates in ovens or heating blocks with carefully controlled times to minimize edge effects (literature). Some formulations allow lower temperatures with longer times.
• Detection: Measure absorbance near 595–600 nm with pathlength correction if available. Read within a defined window as color can slowly evolve or fade.
• Standards: Prepare a fresh standard curve (e.g., calf thymus DNA) in the same buffer as samples, spanning the expected range. Include blanks.
• Interference controls: Optional RNase treatment reduces RNA contribution; include spike-recovery wells to assess matrix effects.

Expected performance (literature): Linear response over sub-µg to a few µg DNA per well, with CVs dependent on heating uniformity and plate handling. Actual performance for this specific kit is not specified; consult CoA/Spec Sheet.

Safety and Handling

Safety information specific to this kit’s components (GHS classification, pictograms, H-statements, and exact hazards) is not provided here.

Item-specific safety:

• GHS Classification: Not specified for this item; refer to SDS.
• Signal Word / Pictograms / H-Statements: Not specified for this item; refer to SDS.

General safety guidance (literature/typical for DPA-based assays; not a substitute for the SDS):

• Diphenylamine and strong acids used in classic DPA reactions can be harmful/irritant and may be combustible or corrosive depending on formulation. Handle reagents in a fume hood, avoid inhalation, and prevent skin/eye contact.
• PPE: Wear lab coat, safety glasses or face shield, and appropriate chemically resistant gloves. Use heat-resistant gloves when handling heated incubations.
• Incompatibilities: Avoid mixing aromatic amines with strong oxidizers; avoid contact with bases if the reagent is acidified. Do not store near ignition sources.
• First aid (general): In case of skin/eye contact, rinse with copious water for ≥15 minutes and seek medical attention. If inhaled, move to fresh air. If ingested, do not induce vomiting and seek medical attention immediately.
• Spill/cleanup: Absorb small spills with inert material, ventilate area, and dispose as hazardous chemical waste per institutional guidelines.

Always review the kit’s SDS and follow your institution’s EHS procedures. The SDS is the authoritative source for hazards, response, and disposal.

Solvent Selection

This product is a ready-to-use assay kit rather than a solvent or solute intended for preparative chemistry. Solvent selection in the conventional sense (e.g., choosing among organic solvents) is not typically applicable.

Practical notes for users (general/literature guidance for DPA microplate assays):

• Sample matrix: Aqueous buffers with minimal sugars and amines are preferred. Tris, phosphate, or TE buffers are commonly used for DNA stocks; EDTA does not usually interfere at low mM levels, but confirm with controls.
• Detergents: Nonionic detergents (e.g., Tween-20) may affect foaming and baseline; minimize unless validated. Ionic detergents (SDS/CTAB) can markedly affect color development—perform compatibility checks.
• Alcohols/salts: Residual ethanol/isopropanol from DNA precipitation and high salt can influence dehydration and reaction kinetics; air-dry pellets thoroughly and, if possible, exchange into assay-compatible buffer.
• Plate materials: Clear, flat-bottom polystyrene microplates suited for visible-range absorbance are standard. Some formulations and hot incubations may warp low-quality plates; use heat-tolerant plateware per the kit insert.

When choosing among DNA quant methods:

• This colorimetric DPA method favors dsDNA selectivity over RNA (literature) and is robust to protein. If samples contain fluorescent contaminants or require green chemistry, consider fluorometric dyes or UV A260 (tradeoffs discussed under Green Alternatives).

Storage and Reconstitution

From Product Data:

• Storage Conditions: Store at -20 °C.
• Shipped In: Ice chest + Ice pads.

Item-specific details not provided here—refer to CoA/Spec Sheet:

• Component list, reconstitution volumes, buffer compositions, preservatives, and stability after opening.

General guidance (not item-specific; follow the kit insert):

• Upon receipt: Verify package integrity and immediately store components at -20 °C as indicated. Avoid repeated freeze–thaw cycles; aliquot reagents if compatible with the kit instructions.
• Thawing: Thaw on ice or at 2–8 °C to minimize degradation of sensitive components. Mix gently to re-homogenize solutions; avoid vortexing if reagents are viscous or foaming.
• Working stability: Many colorimetric reagent mixes have limited stability at room temperature; prepare only the volume needed for the day’s runs. Protect from light if recommended by the manual.
• Plate handling: If hot incubations are required, use heat-resistant plate seals and allow plates to cool before reading to avoid reader condensation artifacts.
• Documentation: Record lot numbers and opening dates; consult the CoA for any lot-specific expiration or on-board stability claims.

Always defer to the official kit protocol for authoritative storage, reconstitution, and usage instructions.

Structure and Identity

This product is a research-use kit for colorimetric DNA quantification using the diphenylamine (DPA) microplate method. It comprises multiple components formulated for plate-based detection; there is no single molecular structure for the kit as a whole.

• SKU: D1528830
• Product Name: DNA Detection Kit (Diphenylamine, Microplate Method)
• Category: Life Science research reagent kit (colorimetric nucleic acid assay)
• Grade: BioReagent (from Product Data)

Item-specific identifiers:

• CAS: Not specified for this item; refer to CoA/Spec Sheet.
• InChIKey: Not specified for this item; refer to CoA/Spec Sheet.
• SMILES: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular Formula: Not specified for this item; refer to CoA/Spec Sheet.
• Molecular Weight: Not specified for this item; refer to CoA/Spec Sheet.

General/literature context (for the core chemistry):

• Principal chromogenic reaction: diphenylamine condenses with deoxyribose (from depurinated DNA under strong acid) to form a blue-colored carbocationic species measurable at ~600 nm (literature). The signal is largely selective for deoxyribose vs. ribose, providing preference for DNA over RNA (literature).
• Typical 2D features involved (literature): diphenylamine (an aniline bearing a phenyl substituent on nitrogen) acts as the aromatic amine nucleophile; the sugar-derived aldehydic intermediates form colored conjugated species under dehydrating acid conditions.

Note: The exact component compositions and concentrations in this kit are proprietary/unspecified here; consult the kit manual and CoA for definitive identity details.

Synthetic Utility

Not applicable in the classical organic-synthesis sense: this is an analytical/colorimetric assay kit, not a building block or reagent intended for chemical synthesis.

General chemical insight (literature) relevant to the assay’s chromogenic reaction:

• Functional groups involved: 2-deoxyribose-derived aldehydes (generated from DNA under acid/heat) condense with an aniline-type nucleophile (diphenylamine), forming a conjugated cationic species responsible for the blue coloration.
• Mechanistic notes: The pathway involves depurination of DNA to free abasic sugar units, dehydration to furfural-like intermediates, and electrophilic aromatic substitution/condensation with the amine under dehydrating conditions. The final chromophore’s intensity correlates with the amount of deoxyribose present.
• Selectivity arises from the absence of the 2′-OH in deoxyribose versus ribose, which affects dehydration kinetics and intermediate stability under the assay conditions (literature).

Practical implications:

• Because the chemistry reports total deoxyribose equivalents, the assay is sensitive to sample treatments that modify sugars (e.g., oxidative damage) and to exogenous sugars in the matrix that may generate background. Careful sample cleanup and matched standards help maintain accuracy.

For synthetic chemistry workflows, consider this section informational only; the kit is not intended for use as a reagent in transformations.

Target Specificity

This product is not an antibody, probe, or capture reagent with molecular target specificity in the immunochemical sense. No antigen/epitope, clone, isotype, or species reactivity applies.

Assay analyte (general): The colorimetric chemistry responds predominantly to deoxyribose released from DNA under assay conditions, offering functional selectivity for DNA over RNA (literature). The degree of selectivity and potential cross-reactivity depend on formulation and conditions, which are not specified here. Refer to the kit manual for any validated specificity data.