سياسة الشحن

All Goods shall be suitably packed in Yeasen standard shipment packaging, marked, and shipped in accordance with Yeasen’s applicable specifications (or if no specifications are provided, in accordance with reasonable commercial practices) using a carrier of Yeasen’s choice. Goods may be shipped, depending on lead time and availability, in installments. Each installment shall be invoiced and considered a separate sale. Unless otherwise agreed, Buyer shall clear any imported Goods at the point of import and pay all relevant duties. Delivery terms (Incoterms 2010) shall be set forth in any Quotation.

While Yeasen will endeavor to ship as soon as practicable, Yeasen makes no guarantee that any products will be available at any particular date or that shipping will be completed within any particular time frame.  Yeasen is not liable for any loss or damage during the course of shipment. This includes accidents, theft, vandalism, labor difficulties, or disputes, weather extremes, other acts of nature, or other circumstances causing a delay in delivery. Freight or shipping and handling charges will be prepaid and added to your invoice.

Delivery. Yeasen shall make a commercially reasonable attempt to deliver the Goods at the time stated in the order confirmation (when applicable) but such dates are estimates only and are not guaranteed. Such dates shall not constitute a term or condition of the Agreement between Yeasen and Buyer. Yeasen accepts no liability whatsoever to meet such dates and such failure shall not entitle Buyer to repudiate or cancel a PO. If Yeasen delivers any Goods in quantities that are less than the quantities specified in the PO, Buyer shall notify Yeasen of the discrepancy and Yeasen shall deliver the confirmed missing allotment of Goods. If Yeasen delivers any Goods in quantities in excess of the quantities specified in the PO, Buyer shall return the amount of the overshipment to Yeasen or notify Yeasen of intention to retain such overshipment. Buyer shall pay for those quantities of Goods actually accepted by Buyer.

Shipping Conditions for Yeasen Enzymes

To ensure optimal enzyme quality during transportation, Yeasen recommends shipping enzymes using Yeasen-certified gel ice packs.

Yeasen routinely dispatches enzymes in insulated polystyrene containers combined with gel ice packs, and distributors are advised to follow the same shipping practice. Prior to use, the gel ice packs are conditioned at −20 °C for no less than 72 hours, and the insulated boxes are securely sealed. Validation studies confirm that this packaging configuration maintains internal temperatures at ≤ 4 °C for over 24 hours and ≤ 10 °C for over 48 hours. Comparative testing has demonstrated no measurable difference in enzyme stability or performance between products shipped with gel ice packs and those transported on dry ice.

Although Yeasen enzymes are recommended for long-term storage at −20 °C, brief exposure to +4 °C to +10 °C during transportation does not compromise enzyme integrity. In fact, throughout the purification workflow—spanning up to three weeks—enzymes are routinely handled within this temperature range while being separated from proteases and other destabilizing impurities.

Each enzyme formulation is supplied in a dedicated storage buffer specifically designed to support extended stability. Yeasen enzymes are formulated in 50% glycerol-based buffers, allowing them to remain unfrozen at temperatures as low as −35 °C. However, shipping under excessively cold conditions, such as with dry ice, may cause freezing. Repeated freeze–thaw events can negatively impact protein activity. It should be noted that Yeasen enzymes are highly purified and free from harmful nuclease or protease contaminants; activity loss at 4 °C is typically associated with such impurities rather than intrinsic enzyme instability.

While the majority of Yeasen products are stored at −20 °C, certain enzymes require alternative storage or shipping conditions, including +4 °C, −70 °C, or dry ice transport. These special requirements are clearly indicated on the product datasheet and/or accompanying shipping documentation.